diff --git a/.github/actions/spell-check/expect.txt b/.github/actions/spell-check/expect.txt
index 7619c20cef..e8af95b8ed 100644
--- a/.github/actions/spell-check/expect.txt
+++ b/.github/actions/spell-check/expect.txt
@@ -2003,6 +2003,7 @@ unregistering
 unremapped
 unsubscribe
 unvirtualized
+unwide
 UOffset
 UOI
 Updatelayout
diff --git a/src/common/utils/string_utils.h b/src/common/utils/string_utils.h
index 27bf64b15b..cd209eb5aa 100644
--- a/src/common/utils/string_utils.h
+++ b/src/common/utils/string_utils.h
@@ -54,3 +54,12 @@ inline void replace_chars(std::basic_string<CharT>& s,
         std::replace(begin(s), end(s), c, replacement_char);
     }
 }
+
+inline std::string unwide(const std::wstring& wide)
+{
+    std::string result(wide.length(), 0);
+    std::transform(begin(wide), end(wide), result.begin(), [](const wchar_t c) {
+        return static_cast<char>(c);
+    });
+    return result;
+}
diff --git a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.idl b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.idl
index c488560308..c6b86bfb77 100644
--- a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.idl
+++ b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.idl
@@ -14,6 +14,7 @@ namespace PowerRenameUI
         ExplorerItemsSource ExplorerItems { get; };
         Windows.Foundation.Collections.IObservableVector<PatternSnippet> SearchRegExShortcuts { get; };
         Windows.Foundation.Collections.IObservableVector<PatternSnippet> DateTimeShortcuts { get; };
+        Windows.Foundation.Collections.IObservableVector<PatternSnippet> CounterShortcuts { get; };
 
         String OriginalCount;
         String RenamedCount;
diff --git a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml
index 30d21d105a..cecbeea866 100644
--- a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml
+++ b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml
@@ -323,6 +323,8 @@
                             <Flyout x:Name="DateTimeFlyout" ShouldConstrainToRootBounds="False">
                                 <Grid>
                                     <Grid.RowDefinitions>
+                                        <RowDefinition Height="28" />
+                                        <RowDefinition Height="Auto" />
                                         <RowDefinition Height="28" />
                                         <RowDefinition Height="*" />
                                     </Grid.RowDefinitions>
@@ -364,7 +366,45 @@
                                             </DataTemplate>
                                         </ListView.ItemTemplate>
                                     </ListView>
-
+                                    <TextBlock x:Uid="CounterCheatSheet_Title"
+                                            Margin="0,10,0,0"
+                                            FontWeight="SemiBold" Grid.Row="2" />
+                                    <ListView Margin="-4,12,0,0"
+                                            IsItemClickEnabled="True"
+                                            ItemClick="DateTimeItemClick"
+                                            ItemsSource="{x:Bind CounterShortcuts}"
+                                            SelectionMode="None" Grid.Row="3">
+                                        <ListView.ItemTemplate>
+                                            <DataTemplate
+                                                    x:DataType="local:PatternSnippet">
+                                                <Grid Margin="-10,0,0,0"
+                                                        ColumnSpacing="8">
+                                                    <Grid.ColumnDefinitions>
+                                                        <ColumnDefinition
+                                                                Width="Auto" />
+                                                        <ColumnDefinition
+                                                                Width="*" />
+                                                    </Grid.ColumnDefinitions>
+                                                    <Border Padding="8"
+                                                            HorizontalAlignment="Left"
+                                                            Background="{ThemeResource ButtonBackground}"
+                                                            BorderBrush="{ThemeResource ButtonBorderBrush}"
+                                                            BorderThickness="1"
+                                                            CornerRadius="4">
+                                                        <TextBlock
+                                                                FontFamily="Consolas"
+                                                                Foreground="{ThemeResource ButtonForeground}"
+                                                                Text="{x:Bind Code}" />
+                                                    </Border>
+                                                    <TextBlock Grid.Column="1"
+                                                            VerticalAlignment="Center"
+                                                            FontSize="12"
+                                                            Foreground="{ThemeResource TextFillColorSecondaryBrush}"
+                                                            Text="{x:Bind Description}" />
+                                                </Grid>
+                                            </DataTemplate>
+                                        </ListView.ItemTemplate>
+                                    </ListView>
                                 </Grid>
                             </Flyout>
                         </Button.Flyout>
diff --git a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.cpp b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.cpp
index b80dade90c..4802f820fc 100644
--- a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.cpp
+++ b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.cpp
@@ -196,6 +196,13 @@ namespace winrt::PowerRenameUI::implementation
         m_dateTimeShortcuts.Append(winrt::make<PatternSnippet>(L"$ff", manager.MainResourceMap().GetValue(L"Resources/DateTimeCheatSheet_MilliSeconds2D").ValueAsString()));
         m_dateTimeShortcuts.Append(winrt::make<PatternSnippet>(L"$f", manager.MainResourceMap().GetValue(L"Resources/DateTimeCheatSheet_MilliSeconds1D").ValueAsString()));
 
+        m_CounterShortcuts = winrt::single_threaded_observable_vector<PowerRenameUI::PatternSnippet>();
+        m_CounterShortcuts.Append(winrt::make<PatternSnippet>(L"${}", manager.MainResourceMap().GetValue(L"Resources/CounterCheatSheet_Simple").ValueAsString()));
+        m_CounterShortcuts.Append(winrt::make<PatternSnippet>(L"${start=10}", manager.MainResourceMap().GetValue(L"Resources/CounterCheatSheet_Start").ValueAsString()));
+        m_CounterShortcuts.Append(winrt::make<PatternSnippet>(L"${increment=5}", manager.MainResourceMap().GetValue(L"Resources/CounterCheatSheet_Increment").ValueAsString()));
+        m_CounterShortcuts.Append(winrt::make<PatternSnippet>(L"${padding=8}", manager.MainResourceMap().GetValue(L"Resources/CounterCheatSheet_Padding").ValueAsString()));
+        m_CounterShortcuts.Append(winrt::make<PatternSnippet>(L"${increment=3,padding=4,start=900}", manager.MainResourceMap().GetValue(L"Resources/CounterCheatSheet_Complex").ValueAsString()));
+
         InitializeComponent();
 
         listView_ExplorerItems().ApplyTemplate();
diff --git a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.h b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.h
index 70759e3ff7..88243af06d 100644
--- a/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.h
+++ b/src/modules/powerrename/PowerRenameUILib/PowerRenameXAML/MainWindow.xaml.h
@@ -81,6 +81,8 @@ namespace winrt::PowerRenameUI::implementation
         PowerRenameUI::ExplorerItemsSource ExplorerItems() { return m_explorerItems; }
         winrt::Windows::Foundation::Collections::IObservableVector<PowerRenameUI::PatternSnippet> SearchRegExShortcuts() { return m_searchRegExShortcuts; }
         winrt::Windows::Foundation::Collections::IObservableVector<PowerRenameUI::PatternSnippet> DateTimeShortcuts() { return m_dateTimeShortcuts; }
+        winrt::Windows::Foundation::Collections::IObservableVector<PowerRenameUI::PatternSnippet> CounterShortcuts() { return m_CounterShortcuts; }
+
         hstring OriginalCount();
         void OriginalCount(hstring value);
         hstring RenamedCount();
@@ -100,6 +102,7 @@ namespace winrt::PowerRenameUI::implementation
         PowerRenameUI::ExplorerItemsSource m_explorerItems;
         winrt::Windows::Foundation::Collections::IObservableVector<PowerRenameUI::PatternSnippet> m_searchRegExShortcuts;
         winrt::Windows::Foundation::Collections::IObservableVector<PowerRenameUI::PatternSnippet> m_dateTimeShortcuts;
+        winrt::Windows::Foundation::Collections::IObservableVector<PowerRenameUI::PatternSnippet> m_CounterShortcuts;
 
         // Used by PowerRenameManagerEvents
         HRESULT OnRename(_In_ IPowerRenameItem* renameItem);
diff --git a/src/modules/powerrename/PowerRenameUILib/Strings/en-us/Resources.resw b/src/modules/powerrename/PowerRenameUILib/Strings/en-us/Resources.resw
index fa1e7cf8e9..a07c601c69 100644
--- a/src/modules/powerrename/PowerRenameUILib/Strings/en-us/Resources.resw
+++ b/src/modules/powerrename/PowerRenameUILib/Strings/en-us/Resources.resw
@@ -150,6 +150,24 @@
   <data name="ReplaceBox.PlaceholderText" xml:space="preserve">
     <value>Replace with</value>
   </data>
+  <data name="CounterCheatSheet_Title.Text" xml:space="preserve">
+    <value>Replace using advanced counter syntax.</value>
+  </data>
+  <data name="CounterCheatSheet_Simple" xml:space="preserve">
+    <value>A simple counter that you can use anywhere in a replace string.</value>
+  </data>
+  <data name="CounterCheatSheet_Start" xml:space="preserve">
+    <value>A counter with a customized start value.</value>
+  </data>
+  <data name="CounterCheatSheet_Increment" xml:space="preserve">
+    <value>A counter with a customized increment value.</value>
+  </data>
+  <data name="CounterCheatSheet_Padding" xml:space="preserve">
+    <value>A counter with a customized number of leading padding zeroes.</value>
+  </data>
+  <data name="CounterCheatSheet_Complex" xml:space="preserve">
+    <value>A counter showing multiple customized properties.</value>
+  </data>
   <data name="DateTimeCheatSheet_Title.Text" xml:space="preserve">
     <value>Replace using file creation date and time</value>
   </data>
diff --git a/src/modules/powerrename/lib/Enumerating.cpp b/src/modules/powerrename/lib/Enumerating.cpp
new file mode 100644
index 0000000000..1ea275720c
--- /dev/null
+++ b/src/modules/powerrename/lib/Enumerating.cpp
@@ -0,0 +1,46 @@
+#include <pch.h>
+
+#include "Enumerating.h"
+
+#include <common\utils\string_utils.h>
+
+std::vector<EnumOptions> parseEnumOptions(const std::wstring& replaceWith)
+{
+    static const std::wregex enumStartRegex(LR"(start=(\d+))");
+    static const std::wregex enumIncrementRegex(LR"(increment=(-?\d+))");
+    static const std::wregex enumPaddingRegex(LR"(padding=(\d+))");
+
+    std::string buf;
+    std::vector<EnumOptions> options;
+    std::wregex enumGroupRegex(LR"(\$\{.*?\})");
+    for (std::wsregex_iterator i{ begin(replaceWith), end(replaceWith), enumGroupRegex }, end; i != end; ++i)
+    {
+        std::wsmatch match = *i;
+        std::wstring matchString = match.str();
+
+        EnumOptions option;
+        option.replaceStrSpan.offset = match.position();
+        option.replaceStrSpan.length = match.length();
+
+        std::wsmatch subMatch;
+        if (std::regex_search(matchString, subMatch, enumStartRegex))
+        {
+            buf = unwide(subMatch[1].str());
+            std::from_chars(buf.data(), buf.data() + buf.size(), option.start.emplace());
+        }
+        if (std::regex_search(matchString, subMatch, enumIncrementRegex))
+        {
+            buf = unwide(subMatch[1].str());
+            std::from_chars(buf.data(), buf.data() + buf.size(), option.increment.emplace());
+        }
+        if (std::regex_search(matchString, subMatch, enumPaddingRegex))
+        {
+            buf = unwide(subMatch[1].str());
+            std::from_chars(buf.data(), buf.data() + buf.size(), option.padding.emplace());
+        }
+
+        options.emplace_back(std::move(option));
+    }
+
+    return options;
+}
diff --git a/src/modules/powerrename/lib/Enumerating.h b/src/modules/powerrename/lib/Enumerating.h
new file mode 100644
index 0000000000..7318daa66d
--- /dev/null
+++ b/src/modules/powerrename/lib/Enumerating.h
@@ -0,0 +1,55 @@
+#pragma once
+
+#include "pch.h"
+
+struct EnumSpan
+{
+    size_t offset = 0;
+    size_t length = 0;
+};
+
+struct EnumOptions
+{
+    std::optional<int> start;
+    std::optional<int> increment;
+    std::optional<uint32_t> padding;
+
+    EnumSpan replaceStrSpan;
+
+    std::strong_ordering operator<=>(const EnumOptions& rhs) const noexcept
+    {
+        return std::make_tuple(start, increment, padding) <=> std::make_tuple(rhs.start, rhs.increment, rhs.padding);
+    }
+
+    bool operator==(const EnumOptions& rhs) const noexcept
+    {
+        return std::make_tuple(start, increment, padding) == std::make_tuple(rhs.start, rhs.increment, rhs.padding);
+    }
+};
+
+std::vector<EnumOptions> parseEnumOptions(const std::wstring& replaceWith);
+
+struct Enumerator
+{
+    inline Enumerator(EnumOptions options) :
+        start{ options.start.value_or(0) }, increment{ options.increment.value_or(1) }, padding{ options.padding.value_or(0) }, replaceStrSpan{ options.replaceStrSpan }
+    {
+    }
+
+    inline int32_t enumerate(const unsigned long index) const { return start + static_cast<int32_t>(index * increment); }
+
+    inline size_t printTo(wchar_t* buf, const size_t bufSize, const unsigned long index) const
+    {
+        const int32_t enumeratedIndex = enumerate(index);
+        wchar_t format[32];
+        swprintf_s(format, sizeof(format) / sizeof(wchar_t), L"%%0%ud", padding);
+        return swprintf_s(buf, bufSize, format, enumeratedIndex);
+    }
+
+    EnumSpan replaceStrSpan;
+
+private:
+    int start;
+    int increment;
+    uint32_t padding;
+};
diff --git a/src/modules/powerrename/lib/Helpers.cpp b/src/modules/powerrename/lib/Helpers.cpp
index ecd823e4d7..73991c8e9b 100644
--- a/src/modules/powerrename/lib/Helpers.cpp
+++ b/src/modules/powerrename/lib/Helpers.cpp
@@ -188,7 +188,7 @@ HRESULT GetTransformedFileName(_Out_ PWSTR result, UINT cchMax, _In_ PCWSTR sour
             {
                 hr = StringCchCopy(result, cchMax, source);
             }
-        } 
+        }
         else if (flags & Capitalized)
         {
             if (!(flags & ExtensionOnly))
@@ -234,15 +234,13 @@ HRESULT GetTransformedFileName(_Out_ PWSTR result, UINT cchMax, _In_ PCWSTR sour
     return hr;
 }
 
-bool isFileTimeUsed(_In_ PCWSTR source) 
+bool isFileTimeUsed(_In_ PCWSTR source)
 {
     bool used = false;
-    std::wstring patterns[] = { L"(([^\\$]|^)(\\$\\$)*)\\$Y", L"(([^\\$]|^)(\\$\\$)*)\\$M", L"(([^\\$]|^)(\\$\\$)*)\\$D", 
-        L"(([^\\$]|^)(\\$\\$)*)\\$h", L"(([^\\$]|^)(\\$\\$)*)\\$m", L"(([^\\$]|^)(\\$\\$)*)\\$s", L"(([^\\$]|^)(\\$\\$)*)\\$f" };
-    size_t patternsLength = ARRAYSIZE(patterns);
-    for (size_t i = 0; !used && i < patternsLength; i++)
+    static const std::array patterns = { std::wregex{ L"(([^\\$]|^)(\\$\\$)*)\\$Y" }, std::wregex{ L"(([^\\$]|^)(\\$\\$)*)\\$M" }, std::wregex{ L"(([^\\$]|^)(\\$\\$)*)\\$D" }, std::wregex{ L"(([^\\$]|^)(\\$\\$)*)\\$h" }, std::wregex{ L"(([^\\$]|^)(\\$\\$)*)\\$m" }, std::wregex{ L"(([^\\$]|^)(\\$\\$)*)\\$s" }, std::wregex{ L"(([^\\$]|^)(\\$\\$)*)\\$f" } };
+    for (size_t i = 0; !used && i < patterns.size(); i++)
     {
-        if (std::regex_search(source, std::wregex(patterns[i])))
+        if (std::regex_search(source, patterns[i]))
         {
             used = true;
         }
@@ -253,7 +251,7 @@ bool isFileTimeUsed(_In_ PCWSTR source)
 HRESULT GetDatedFileName(_Out_ PWSTR result, UINT cchMax, _In_ PCWSTR source, SYSTEMTIME fileTime)
 {
     std::locale::global(std::locale(""));
-    HRESULT hr = E_INVALIDARG;     
+    HRESULT hr = E_INVALIDARG;
     if (source && wcslen(source) > 0)
     {
         std::wstring res(source);
@@ -274,17 +272,17 @@ HRESULT GetDatedFileName(_Out_ PWSTR result, UINT cchMax, _In_ PCWSTR source, SY
 
         StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%d"), L"$01", (fileTime.wYear % 10));
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$Y"), replaceTerm);
-        
+
         GetDateFormatEx(localeName, NULL, &fileTime, L"MMMM", formattedDate, MAX_PATH, NULL);
         formattedDate[0] = towupper(formattedDate[0]);
         StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%s"), L"$01", formattedDate);
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$MMMM"), replaceTerm);
-        
+
         GetDateFormatEx(localeName, NULL, &fileTime, L"MMM", formattedDate, MAX_PATH, NULL);
         formattedDate[0] = towupper(formattedDate[0]);
         StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%s"), L"$01", formattedDate);
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$MMM"), replaceTerm);
-                
+
         StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%02d"), L"$01", fileTime.wMonth);
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$MM"), replaceTerm);
 
@@ -295,7 +293,7 @@ HRESULT GetDatedFileName(_Out_ PWSTR result, UINT cchMax, _In_ PCWSTR source, SY
         formattedDate[0] = towupper(formattedDate[0]);
         StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%s"), L"$01", formattedDate);
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$DDDD"), replaceTerm);
-        
+
         GetDateFormatEx(localeName, NULL, &fileTime, L"ddd", formattedDate, MAX_PATH, NULL);
         formattedDate[0] = towupper(formattedDate[0]);
         StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%s"), L"$01", formattedDate);
@@ -328,10 +326,10 @@ HRESULT GetDatedFileName(_Out_ PWSTR result, UINT cchMax, _In_ PCWSTR source, SY
         StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%03d"), L"$01", fileTime.wMilliseconds);
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$fff"), replaceTerm);
 
-        StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%02d"), L"$01", fileTime.wMilliseconds/10);
+        StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%02d"), L"$01", fileTime.wMilliseconds / 10);
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$ff"), replaceTerm);
 
-        StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%d"), L"$01", fileTime.wMilliseconds/100);
+        StringCchPrintf(replaceTerm, MAX_PATH, TEXT("%s%d"), L"$01", fileTime.wMilliseconds / 100);
         res = regex_replace(res, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$f"), replaceTerm);
 
         hr = StringCchCopy(result, cchMax, res.c_str());
diff --git a/src/modules/powerrename/lib/PowerRenameInterfaces.h b/src/modules/powerrename/lib/PowerRenameInterfaces.h
index 6fcc25368d..974fee5425 100644
--- a/src/modules/powerrename/lib/PowerRenameInterfaces.h
+++ b/src/modules/powerrename/lib/PowerRenameInterfaces.h
@@ -58,7 +58,7 @@ public:
     IFACEMETHOD(PutFlags)(_In_ DWORD flags) = 0;
     IFACEMETHOD(PutFileTime)(_In_ SYSTEMTIME fileTime) = 0;
     IFACEMETHOD(ResetFileTime)() = 0;
-    IFACEMETHOD(Replace)(_In_ PCWSTR source, _Outptr_ PWSTR* result) = 0;
+    IFACEMETHOD(Replace)(_In_ PCWSTR source, _Outptr_ PWSTR* result, unsigned long& enumIndex) = 0;
 };
 
 interface __declspec(uuid("C7F59201-4DE1-4855-A3A2-26FC3279C8A5")) IPowerRenameItem : public IUnknown
diff --git a/src/modules/powerrename/lib/PowerRenameLib.vcxproj b/src/modules/powerrename/lib/PowerRenameLib.vcxproj
index be76c5f5ab..e330dfb3e2 100644
--- a/src/modules/powerrename/lib/PowerRenameLib.vcxproj
+++ b/src/modules/powerrename/lib/PowerRenameLib.vcxproj
@@ -31,6 +31,7 @@
     </ClCompile>
   </ItemDefinitionGroup>
   <ItemGroup>
+    <ClInclude Include="Enumerating.h" />
     <ClInclude Include="Helpers.h" />
     <ClInclude Include="MRUListHandler.h" />
     <ClInclude Include="PowerRenameEnum.h" />
@@ -47,6 +48,7 @@
     <ClInclude Include="trace.h" />
   </ItemGroup>
   <ItemGroup>
+    <ClCompile Include="Enumerating.cpp" />
     <ClCompile Include="Helpers.cpp" />
     <ClCompile Include="MRUListHandler.cpp" />
     <ClCompile Include="PowerRenameEnum.cpp" />
diff --git a/src/modules/powerrename/lib/PowerRenameManager.cpp b/src/modules/powerrename/lib/PowerRenameManager.cpp
index 379e349e02..b6641374ba 100644
--- a/src/modules/powerrename/lib/PowerRenameManager.cpp
+++ b/src/modules/powerrename/lib/PowerRenameManager.cpp
@@ -923,7 +923,7 @@ DWORD WINAPI CPowerRenameManager::s_regexWorkerThread(_In_ void* pv)
                 winrt::check_hresult(pwtd->spsrm->GetRenameRegEx(&spRenameRegEx));
 
                 UINT itemCount = 0;
-                unsigned long itemEnumIndex = 1;
+                unsigned long itemEnumIndex = 0;
                 winrt::check_hresult(pwtd->spsrm->GetItemCount(&itemCount));
 
                 for (UINT u = 0; u < itemCount; u++)
diff --git a/src/modules/powerrename/lib/PowerRenameRegEx.cpp b/src/modules/powerrename/lib/PowerRenameRegEx.cpp
index ec374b192d..8fdeb67cf1 100644
--- a/src/modules/powerrename/lib/PowerRenameRegEx.cpp
+++ b/src/modules/powerrename/lib/PowerRenameRegEx.cpp
@@ -1,5 +1,6 @@
 #include "pch.h"
 #include "PowerRenameRegEx.h"
+#include "Enumerating.h"
 #include "Settings.h"
 #include <regex>
 #include <string>
@@ -7,15 +8,17 @@
 #include <boost/regex.hpp>
 #include <helpers.h>
 
-using namespace std;
+using std::conditional_t;
 using std::regex_error;
 
-IFACEMETHODIMP_(ULONG) CPowerRenameRegEx::AddRef()
+IFACEMETHODIMP_(ULONG)
+CPowerRenameRegEx::AddRef()
 {
     return InterlockedIncrement(&m_refCount);
 }
 
-IFACEMETHODIMP_(ULONG) CPowerRenameRegEx::Release()
+IFACEMETHODIMP_(ULONG)
+CPowerRenameRegEx::Release()
 {
     long refCount = InterlockedDecrement(&m_refCount);
 
@@ -127,6 +130,26 @@ IFACEMETHODIMP CPowerRenameRegEx::GetReplaceTerm(_Outptr_ PWSTR* replaceTerm)
     return hr;
 }
 
+HRESULT CPowerRenameRegEx::_OnEnumerateItemsChanged()
+{
+    m_enumerators.clear();
+    const auto options = parseEnumOptions(m_RawReplaceTerm);
+    for (const auto e : options)
+        m_enumerators.emplace_back(e);
+
+    m_replaceWithEnumeratorOffsets.clear();
+    std::wstring replaceWith{ m_RawReplaceTerm };
+    // Remove counter expressions and calculate their offsets in replaceWith string.
+    int32_t offset = 0;
+    for (const auto& e : options)
+    {
+        replaceWith.erase(e.replaceStrSpan.offset + offset, e.replaceStrSpan.length);
+        m_replaceWithEnumeratorOffsets.push_back(offset);
+        offset -= static_cast<int32_t>(e.replaceStrSpan.length);
+    }
+    return SHStrDup(replaceWith.data(), &m_replaceTerm);
+}
+
 IFACEMETHODIMP CPowerRenameRegEx::PutReplaceTerm(_In_ PCWSTR replaceTerm, bool forceRenaming)
 {
     bool changed = false || forceRenaming;
@@ -134,11 +157,16 @@ IFACEMETHODIMP CPowerRenameRegEx::PutReplaceTerm(_In_ PCWSTR replaceTerm, bool f
     if (replaceTerm)
     {
         CSRWExclusiveAutoLock lock(&m_lock);
-        if (m_replaceTerm == nullptr || lstrcmp(replaceTerm, m_replaceTerm) != 0)
+        if (m_replaceTerm == nullptr || lstrcmp(replaceTerm, m_RawReplaceTerm.c_str()) != 0)
         {
             changed = true;
             CoTaskMemFree(m_replaceTerm);
-            hr = SHStrDup(replaceTerm, &m_replaceTerm);
+            m_RawReplaceTerm = replaceTerm;
+
+            if (m_flags & EnumerateItems)
+                hr = _OnEnumerateItemsChanged();
+            else
+                hr = SHStrDup(replaceTerm, &m_replaceTerm);
         }
     }
 
@@ -160,7 +188,20 @@ IFACEMETHODIMP CPowerRenameRegEx::PutFlags(_In_ DWORD flags)
 {
     if (m_flags != flags)
     {
+        const bool newEnumerate = flags & EnumerateItems;
+        const bool refreshReplaceTerm = !!(m_flags & EnumerateItems) != newEnumerate;
         m_flags = flags;
+        if (refreshReplaceTerm)
+        {
+            CSRWExclusiveAutoLock lock(&m_lock);
+            if (newEnumerate)
+                _OnEnumerateItemsChanged();
+            else
+            {
+                CoTaskMemFree(m_replaceTerm);
+                SHStrDup(m_RawReplaceTerm.c_str(), &m_replaceTerm);
+            }
+        }
         _OnFlagsChanged();
     }
     return S_OK;
@@ -202,7 +243,7 @@ HRESULT CPowerRenameRegEx::s_CreateInstance(_Outptr_ IPowerRenameRegEx** renameR
 {
     *renameRegEx = nullptr;
 
-    CPowerRenameRegEx *newRenameRegEx = new CPowerRenameRegEx();
+    CPowerRenameRegEx* newRenameRegEx = new CPowerRenameRegEx();
     HRESULT hr = E_OUTOFMEMORY;
     if (newRenameRegEx)
     {
@@ -228,7 +269,20 @@ CPowerRenameRegEx::~CPowerRenameRegEx()
     CoTaskMemFree(m_replaceTerm);
 }
 
-HRESULT CPowerRenameRegEx::Replace(_In_ PCWSTR source, _Outptr_ PWSTR* result)
+template<bool Std, class Regex = conditional_t<Std, std::wregex, boost::wregex>, class Options = decltype(Regex::icase)>
+static std::wstring RegexReplaceEx(const std::wstring& source, const std::wstring& searchTerm, const std::wstring& replaceTerm, const bool matchAll, const bool caseInsensitive)
+{
+    Regex pattern(searchTerm, Options::ECMAScript | (caseInsensitive ? Options::icase : Options{}));
+
+    using Flags = conditional_t<Std, std::regex_constants::match_flag_type, boost::regex_constants::match_flags>;
+    const auto flags = matchAll ? Flags::match_default : Flags::format_first_only;
+
+    return regex_replace(source, pattern, replaceTerm, flags);
+}
+
+static constexpr std::array RegexReplaceDispatch = { RegexReplaceEx<true>, RegexReplaceEx<false> };
+
+HRESULT CPowerRenameRegEx::Replace(_In_ PCWSTR source, _Outptr_ PWSTR* result, unsigned long& enumIndex)
 {
     *result = nullptr;
 
@@ -238,7 +292,7 @@ HRESULT CPowerRenameRegEx::Replace(_In_ PCWSTR source, _Outptr_ PWSTR* result)
     {
         return hr;
     }
-    wstring res = source;
+    std::wstring res = source;
     try
     {
         // TODO: creating the regex could be costly.  May want to cache this.
@@ -250,47 +304,49 @@ HRESULT CPowerRenameRegEx::Replace(_In_ PCWSTR source, _Outptr_ PWSTR* result)
                 fileTimeErrorOccurred = true;
         }
 
-        std::wstring sourceToUse(source);
+        std::wstring sourceToUse;
+        std::wstring originalSource;
+        sourceToUse.reserve(MAX_PATH);
+        originalSource.reserve(MAX_PATH);
+        sourceToUse = source;
+        originalSource = sourceToUse;
+
         std::wstring searchTerm(m_searchTerm);
-        std::wstring replaceTerm(L"");
+        std::wstring replaceTerm;
         if (m_useFileTime && !fileTimeErrorOccurred)
         {
-            replaceTerm = wstring(newReplaceTerm);
+            replaceTerm = newReplaceTerm;
         }
         else if (m_replaceTerm)
         {
-            replaceTerm = wstring(m_replaceTerm);
+            replaceTerm = m_replaceTerm;
         }
 
-        replaceTerm = regex_replace(replaceTerm, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$[0]"), L"$1$$$0");
-        replaceTerm = regex_replace(replaceTerm, std::wregex(L"(([^\\$]|^)(\\$\\$)*)\\$([1-9])"), L"$1$0$4");
+        static const std::wregex zeroGroupRegex(L"(([^\\$]|^)(\\$\\$)*)\\$[0]");
+        static const std::wregex otherGroupsRegex(L"(([^\\$]|^)(\\$\\$)*)\\$([1-9])");
 
+        if (m_flags & EnumerateItems)
+        {
+            std::array<wchar_t, MAX_PATH> buffer;
+            int32_t offset = 0;
+
+            for (size_t ei = 0; ei < m_enumerators.size(); ++ei)
+            {
+                const auto& e = m_enumerators[ei];
+                const auto replacementLength = static_cast<int32_t>(e.printTo(buffer.data(), buffer.size(), enumIndex));
+                replaceTerm.insert(e.replaceStrSpan.offset + offset + m_replaceWithEnumeratorOffsets[ei], buffer.data());
+                offset += replacementLength;
+            }
+        }
+
+        bool replacedSomething = false;
         if (m_flags & UseRegularExpressions)
         {
-            if (_useBoostLib)
-            {
-                boost::wregex pattern(m_searchTerm, (!(m_flags & CaseSensitive)) ? boost::regex::icase | boost::regex::ECMAScript : boost::regex::ECMAScript);
-                if (m_flags & MatchAllOccurrences)
-                {
-                    res = boost::regex_replace(wstring(source), pattern, replaceTerm);
-                }
-                else
-                {
-                    res = boost::regex_replace(wstring(source), pattern, replaceTerm, boost::regex_constants::format_first_only);
-                }
-            }
-            else
-            {
-                std::wregex pattern(m_searchTerm, (!(m_flags & CaseSensitive)) ? regex_constants::icase | regex_constants::ECMAScript : regex_constants::ECMAScript);
-                if (m_flags & MatchAllOccurrences)
-                {
-                    res = regex_replace(wstring(source), pattern, replaceTerm);
-                }
-                else
-                {
-                    res = regex_replace(wstring(source), pattern, replaceTerm, regex_constants::format_first_only);
-                }
-            }
+            replaceTerm = regex_replace(replaceTerm, zeroGroupRegex, L"$1$$$0");
+            replaceTerm = regex_replace(replaceTerm, otherGroupsRegex, L"$1$0$4");
+
+            res = RegexReplaceDispatch[_useBoostLib](source, m_searchTerm, replaceTerm, m_flags & MatchAllOccurrences, !(m_flags & CaseSensitive));
+            replacedSomething = originalSource != res;
         }
         else
         {
@@ -303,16 +359,17 @@ HRESULT CPowerRenameRegEx::Replace(_In_ PCWSTR source, _Outptr_ PWSTR* result)
                 {
                     res = sourceToUse.replace(pos, searchTerm.length(), replaceTerm);
                     pos += replaceTerm.length();
+                    replacedSomething = true;
                 }
-
                 if (!(m_flags & MatchAllOccurrences))
                 {
                     break;
                 }
             } while (pos != std::string::npos);
         }
-
         hr = SHStrDup(res.c_str(), result);
+        if (replacedSomething)
+            enumIndex++;
     }
     catch (regex_error e)
     {
diff --git a/src/modules/powerrename/lib/PowerRenameRegEx.h b/src/modules/powerrename/lib/PowerRenameRegEx.h
index dae5f04380..1b4e20a713 100644
--- a/src/modules/powerrename/lib/PowerRenameRegEx.h
+++ b/src/modules/powerrename/lib/PowerRenameRegEx.h
@@ -1,9 +1,8 @@
 #pragma once
 #include "pch.h"
-#include <vector>
-#include <string>
 #include "srwlock.h"
 
+#include "Enumerating.h"
 #include "PowerRenameInterfaces.h"
 
 #define DEFAULT_FLAGS 0
@@ -12,7 +11,7 @@ class CPowerRenameRegEx : public IPowerRenameRegEx
 {
 public:
     // IUnknown
-    IFACEMETHODIMP  QueryInterface(_In_ REFIID iid, _Outptr_ void** resultInterface);
+    IFACEMETHODIMP QueryInterface(_In_ REFIID iid, _Outptr_ void** resultInterface);
     IFACEMETHODIMP_(ULONG) AddRef();
     IFACEMETHODIMP_(ULONG) Release();
 
@@ -27,9 +26,9 @@ public:
     IFACEMETHODIMP PutFlags(_In_ DWORD flags);
     IFACEMETHODIMP PutFileTime(_In_ SYSTEMTIME fileTime);
     IFACEMETHODIMP ResetFileTime();
-    IFACEMETHODIMP Replace(_In_ PCWSTR source, _Outptr_ PWSTR* result);
+    IFACEMETHODIMP Replace(_In_ PCWSTR source, _Outptr_ PWSTR* result, unsigned long& enumIndex);
 
-    static HRESULT s_CreateInstance(_Outptr_ IPowerRenameRegEx **renameRegEx);
+    static HRESULT s_CreateInstance(_Outptr_ IPowerRenameRegEx** renameRegEx);
 
 protected:
     CPowerRenameRegEx();
@@ -39,6 +38,7 @@ protected:
     void _OnReplaceTermChanged();
     void _OnFlagsChanged();
     void _OnFileTimeChanged();
+    HRESULT _OnEnumerateItemsChanged();
 
     size_t _Find(std::wstring data, std::wstring toSearch, bool caseInsensitive, size_t pos);
 
@@ -46,8 +46,9 @@ protected:
     DWORD m_flags = DEFAULT_FLAGS;
     PWSTR m_searchTerm = nullptr;
     PWSTR m_replaceTerm = nullptr;
+    std::wstring m_RawReplaceTerm; 
 
-    SYSTEMTIME m_fileTime = {0};
+    SYSTEMTIME m_fileTime = { 0 };
     bool m_useFileTime = false;
 
     CSRWLock m_lock;
@@ -55,6 +56,9 @@ protected:
 
     DWORD m_cookie = 0;
 
+    std::vector<Enumerator> m_enumerators;
+    std::vector<int32_t> m_replaceWithEnumeratorOffsets;
+
     struct RENAME_REGEX_EVENT
     {
         IPowerRenameRegExEvents* pEvents;
diff --git a/src/modules/powerrename/lib/Renaming.cpp b/src/modules/powerrename/lib/Renaming.cpp
index ee070bb831..bf27500529 100644
--- a/src/modules/powerrename/lib/Renaming.cpp
+++ b/src/modules/powerrename/lib/Renaming.cpp
@@ -86,7 +86,7 @@ bool DoRename(CComPtr<IPowerRenameRegEx>& spRenameRegEx, unsigned long& itemEnum
 
     // Failure here means we didn't match anything or had nothing to match
     // Call put_newName with null in that case to reset it
-    winrt::check_hresult(spRenameRegEx->Replace(sourceName, &newName));
+    winrt::check_hresult(spRenameRegEx->Replace(sourceName, &newName, itemEnumIndex));
 
     if (useFileTime)
     {
@@ -166,17 +166,6 @@ bool DoRename(CComPtr<IPowerRenameRegEx>& spRenameRegEx, unsigned long& itemEnum
         newNameToUse = nullptr;
     }
 
-    wchar_t uniqueName[MAX_PATH] = { 0 };
-    if (newNameToUse != nullptr && (flags & EnumerateItems))
-    {
-        unsigned long countUsed = 0;
-        if (GetEnumeratedFileName(uniqueName, ARRAYSIZE(uniqueName), newNameToUse, nullptr, itemEnumIndex, &countUsed))
-        {
-            newNameToUse = uniqueName;
-        }
-        itemEnumIndex++;
-    }
-
     spItem->PutStatus(PowerRenameItemRenameStatus::ShouldRename);
     if (newNameToUse != nullptr)
     {
diff --git a/src/modules/powerrename/lib/pch.h b/src/modules/powerrename/lib/pch.h
index 890021fe33..af9f76bbff 100644
--- a/src/modules/powerrename/lib/pch.h
+++ b/src/modules/powerrename/lib/pch.h
@@ -21,6 +21,12 @@
 #include <shlwapi.h>
 #include <ShlObj_core.h>
 #include <filesystem>
+#include <compare>
+#include <regex>
+#include <vector>
+#include <variant>
+#include <charconv>
+#include <string>
 
 #include <ProjectTelemetry.h>
 
diff --git a/src/modules/powerrename/unittests/CommonRegExTests.h b/src/modules/powerrename/unittests/CommonRegExTests.h
new file mode 100644
index 0000000000..f9cb469fb3
--- /dev/null
+++ b/src/modules/powerrename/unittests/CommonRegExTests.h
@@ -0,0 +1,472 @@
+//#undef TESTS_PARTIAL // Uncomment temporarily to make intellisense work in this file.
+#ifndef TESTS_PARTIAL
+#include "CppUnitTestInclude.h"
+#include "powerrename/lib/Settings.h"
+#include <PowerRenameInterfaces.h>
+#include <PowerRenameRegEx.h>
+
+using namespace Microsoft::VisualStudio::CppUnitTestFramework;
+namespace PowerRenameRegExTests
+{
+TEST_CLASS (SimpleTests)
+{
+public:
+#endif
+
+struct SearchReplaceExpected
+{
+    PCWSTR search;
+    PCWSTR replace;
+    PCWSTR test;
+    PCWSTR expected;
+};
+
+TEST_METHOD (GeneralReplaceTest)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"big") == S_OK);
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"bigbar", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (ReplaceNoMatch)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"notfound") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"big") == S_OK);
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (ReplaceNoSearchOrReplaceTerm)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    PWSTR result = nullptr;
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::IsTrue(result == nullptr);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (ReplaceNoReplaceTerm)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"bar", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (ReplaceEmptyStringReplaceTerm)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"") == S_OK);
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"bar", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifyDefaultFlags)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = 0;
+    Assert::IsTrue(renameRegEx->GetFlags(&flags) == S_OK);
+    Assert::IsTrue(flags == 0);
+}
+
+TEST_METHOD (VerifyCaseSensitiveSearch)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = CaseSensitive;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    SearchReplaceExpected sreTable[] = {
+        { L"Foo", L"Foo", L"FooBar", L"FooBar" },
+        { L"Foo", L"boo", L"FooBar", L"booBar" },
+        { L"Foo", L"boo", L"foobar", L"foobar" },
+        { L"123", L"654", L"123456", L"654456" },
+    };
+
+    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
+        CoTaskMemFree(result);
+    }
+}
+
+TEST_METHOD (VerifyReplaceFirstOnly)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = 0;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    SearchReplaceExpected sreTable[] = {
+        { L"B", L"BB", L"ABA", L"ABBA" },
+        { L"B", L"A", L"ABBBA", L"AABBA" },
+        { L"B", L"BBB", L"ABABAB", L"ABBBABAB" },
+    };
+
+    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
+        CoTaskMemFree(result);
+    }
+}
+
+TEST_METHOD (VerifyReplaceAll)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = MatchAllOccurrences;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    SearchReplaceExpected sreTable[] = {
+        { L"B", L"BB", L"ABA", L"ABBA" },
+        { L"B", L"A", L"ABBBA", L"AAAAA" },
+        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
+    };
+
+    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
+        CoTaskMemFree(result);
+    }
+}
+
+TEST_METHOD (VerifyReplaceAllCaseInsensitive)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = MatchAllOccurrences | CaseSensitive;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    SearchReplaceExpected sreTable[] = {
+        { L"B", L"BB", L"ABA", L"ABBA" },
+        { L"B", L"A", L"ABBBA", L"AAAAA" },
+        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
+        { L"b", L"BBB", L"AbABAb", L"ABBBABABBB" },
+    };
+
+    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
+        CoTaskMemFree(result);
+    }
+}
+
+TEST_METHOD (VerifyReplaceFirstOnlyUseRegEx)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    SearchReplaceExpected sreTable[] = {
+        { L"B", L"BB", L"ABA", L"ABBA" },
+        { L"B", L"A", L"ABBBA", L"AABBA" },
+        { L"B", L"BBB", L"ABABAB", L"ABBBABAB" },
+    };
+
+    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
+        CoTaskMemFree(result);
+    }
+}
+
+TEST_METHOD (VerifyReplaceAllUseRegEx)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = MatchAllOccurrences | UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    SearchReplaceExpected sreTable[] = {
+        { L"B", L"BB", L"ABA", L"ABBA" },
+        { L"B", L"A", L"ABBBA", L"AAAAA" },
+        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
+    };
+
+    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
+        CoTaskMemFree(result);
+    }
+}
+
+TEST_METHOD (VerifyReplaceAllUseRegExCaseSensitive)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = MatchAllOccurrences | UseRegularExpressions | CaseSensitive;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    SearchReplaceExpected sreTable[] = {
+        { L"B", L"BB", L"ABA", L"ABBA" },
+        { L"B", L"A", L"ABBBA", L"AAAAA" },
+        { L"b", L"BBB", L"AbABAb", L"ABBBABABBB" },
+    };
+
+    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
+        CoTaskMemFree(result);
+    }
+}
+
+void VerifyReplaceFirstWildcard(SearchReplaceExpected sreTable[], int tableSize, DWORD flags)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    for (int i = 0; i < tableSize; i++)
+    {
+        PWSTR result = nullptr;
+        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
+        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
+        Assert::AreEqual(sreTable[i].expected, result);
+        CoTaskMemFree(result);
+    }
+}
+
+TEST_METHOD (VerifyReplaceFirstWildCardUseRegex)
+{
+    SearchReplaceExpected sreTable[] = {
+        //search, replace, test, result
+        { L".*", L"Foo", L"AAAAAA", L"Foo" },
+    };
+    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), UseRegularExpressions);
+}
+
+TEST_METHOD (VerifyReplaceFirstWildCardMatchAllOccurrences)
+{
+    SearchReplaceExpected sreTable[] = {
+        //search, replace, test, result
+        { L".*", L"Foo", L"AAAAAA", L"AAAAAA" },
+        { L".*", L"Foo", L".*", L"Foo" },
+        { L".*", L"Foo", L".*Bar.*", L"FooBarFoo" },
+    };
+    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), MatchAllOccurrences);
+}
+
+TEST_METHOD (VerifyReplaceFirstWildNoFlags)
+{
+    SearchReplaceExpected sreTable[] = {
+        //search, replace, test, result
+        { L".*", L"Foo", L"AAAAAA", L"AAAAAA" },
+        { L".*", L"Foo", L".*", L"Foo" },
+    };
+    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), 0);
+}
+
+TEST_METHOD (VerifyEventsFire)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    CMockPowerRenameRegExEvents* mockEvents = new CMockPowerRenameRegExEvents();
+    CComPtr<IPowerRenameRegExEvents> regExEvents;
+    Assert::IsTrue(mockEvents->QueryInterface(IID_PPV_ARGS(&regExEvents)) == S_OK);
+    DWORD cookie = 0;
+    Assert::IsTrue(renameRegEx->Advise(regExEvents, &cookie) == S_OK);
+    DWORD flags = MatchAllOccurrences | UseRegularExpressions | CaseSensitive;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"FOO") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"BAR") == S_OK);
+    Assert::IsTrue(renameRegEx->PutFileTime(SYSTEMTIME{ 0 }) == S_OK);
+    Assert::IsTrue(renameRegEx->ResetFileTime() == S_OK);
+    Assert::IsTrue(lstrcmpi(L"FOO", mockEvents->m_searchTerm) == 0);
+    Assert::IsTrue(lstrcmpi(L"BAR", mockEvents->m_replaceTerm) == 0);
+    Assert::IsTrue(flags == mockEvents->m_flags);
+    Assert::IsTrue(renameRegEx->UnAdvise(cookie) == S_OK);
+    mockEvents->Release();
+}
+
+TEST_METHOD (VerifySimpleCounterNoRegex)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = EnumerateItems;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"$1bar_${}") == S_OK);
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foo$1bar_0", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifySimpleCounterNoEnum)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"$1bar_${}") == S_OK);
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar_${}", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifySimpleCounter)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = EnumerateItems | UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"bar_${}") == S_OK);
+    unsigned long index = {};
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar_0", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifyMultipleCounters)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = EnumerateItems | UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"_${}_bar_${}") == S_OK);
+    unsigned long index = {};
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foo_0_bar_0", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifyCounterIncrementCustomization)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = EnumerateItems | UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"bar_${increment=10}") == S_OK);
+    unsigned long index = 1;
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar_10", result);
+    Assert::AreEqual<unsigned long>(index, 2);
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar_20", result);
+    Assert::AreEqual<unsigned long>(index, 3);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifyCounterStartCustomization)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = EnumerateItems | UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"bar_${start=1000}") == S_OK);
+    unsigned long index = 5;
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar_1005", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifyCounterPaddingCustomization)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = EnumerateItems | UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"bar_${padding=5}") == S_OK);
+    unsigned long index = 204;
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar_00204", result);
+    CoTaskMemFree(result);
+}
+
+TEST_METHOD (VerifyCounterAllCustomizations)
+{
+    CComPtr<IPowerRenameRegEx> renameRegEx;
+    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
+    DWORD flags = EnumerateItems | UseRegularExpressions;
+    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
+    Assert::IsTrue(renameRegEx->PutSearchTerm(L"bar") == S_OK);
+    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"bar_${increment=7,start=993,padding=5}") == S_OK);
+    unsigned long index = 12;
+    PWSTR result = nullptr;
+    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result, index) == S_OK);
+    Assert::AreEqual(L"foobar_01077", result);
+    CoTaskMemFree(result);
+}
+
+#ifndef TESTS_PARTIAL
+};
+}
+#endif
diff --git a/src/modules/powerrename/unittests/CppUnitTestInclude.h b/src/modules/powerrename/unittests/CppUnitTestInclude.h
new file mode 100644
index 0000000000..dce5689675
--- /dev/null
+++ b/src/modules/powerrename/unittests/CppUnitTestInclude.h
@@ -0,0 +1,8 @@
+#pragma once
+// Headers for CppUnitTest
+
+// Suppressing 26466 - Don't use static_cast downcasts - in CppUnitTest.h
+#pragma warning(push)
+#pragma warning(disable : 26466)
+#include "CppUnitTest.h"
+#pragma warning(pop)
diff --git a/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj b/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj
index 0598fb77e6..f64a2e85a3 100644
--- a/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj
+++ b/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj
@@ -38,6 +38,7 @@
     </Link>
   </ItemDefinitionGroup>
   <ItemGroup>
+    <ClInclude Include="CppUnitTestInclude.h" />
     <ClInclude Include="MockPowerRenameItem.h" />
     <ClInclude Include="MockPowerRenameManagerEvents.h" />
     <ClInclude Include="MockPowerRenameRegExEvents.h" />
@@ -45,6 +46,7 @@
     <ClInclude Include="resource.h" />
     <ClInclude Include="targetver.h" />
     <ClInclude Include="TestFileHelper.h" />
+    <ClInclude Include="CommonRegExTests.h" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="MockPowerRenameItem.cpp" />
diff --git a/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj.filters b/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj.filters
index 8708f3397e..db5bc09af4 100644
--- a/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj.filters
+++ b/src/modules/powerrename/unittests/PowerRenameLibUnitTests.vcxproj.filters
@@ -17,9 +17,11 @@
     <ClInclude Include="pch.h" />
     <ClInclude Include="targetver.h" />
     <ClInclude Include="TestFileHelper.h" />
+    <ClInclude Include="CommonRegExTests.h" />
     <ClInclude Include="resource.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="CppUnitTestInclude.h" />
   </ItemGroup>
   <ItemGroup>
     <Filter Include="Resource Files">
diff --git a/src/modules/powerrename/unittests/PowerRenameRegExBoostTests.cpp b/src/modules/powerrename/unittests/PowerRenameRegExBoostTests.cpp
index bb70ebb99b..2bff1a4b9c 100644
--- a/src/modules/powerrename/unittests/PowerRenameRegExBoostTests.cpp
+++ b/src/modules/powerrename/unittests/PowerRenameRegExBoostTests.cpp
@@ -8,14 +8,6 @@ using namespace Microsoft::VisualStudio::CppUnitTestFramework;
 
 namespace PowerRenameRegExBoostTests
 {
-    struct SearchReplaceExpected
-    {
-        PCWSTR search;
-        PCWSTR replace;
-        PCWSTR test;
-        PCWSTR expected;
-    };
-
     TEST_CLASS(SimpleTests)
     {
     public:
@@ -29,241 +21,8 @@ TEST_CLASS_CLEANUP(ClassCleanup)
     CSettingsInstance().SetUseBoostLib(false);
 }
 
-TEST_METHOD(GeneralReplaceTest)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"big") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"bigbar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceNoMatch)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"notfound") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"big") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"foobar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceNoSearchOrReplaceTerm)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(result == nullptr);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceNoReplaceTerm)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"bar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceEmptyStringReplaceTerm)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"bar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(VerifyDefaultFlags)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = 0;
-    Assert::IsTrue(renameRegEx->GetFlags(&flags) == S_OK);
-    Assert::IsTrue(flags == 0);
-}
-
-TEST_METHOD(VerifyCaseSensitiveSearch)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"Foo", L"Foo", L"FooBar", L"FooBar" },
-        { L"Foo", L"boo", L"FooBar", L"booBar" },
-        { L"Foo", L"boo", L"foobar", L"foobar" },
-        { L"123", L"654", L"123456", L"654456" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceFirstOnly)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = 0;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AABBA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABAB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAll)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAllCaseInsensitive)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences | CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
-        { L"b", L"BBB", L"AbABAb", L"ABBBABABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceFirstOnlyUseRegEx)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = UseRegularExpressions;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AABBA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABAB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAllUseRegEx)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences | UseRegularExpressions;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAllUseRegExCaseSensitive)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences | UseRegularExpressions | CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"b", L"BBB", L"AbABAb", L"ABBBABABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
+#define TESTS_PARTIAL
+#include "CommonRegExTests.h"
 
 TEST_METHOD(VerifyMatchAllWildcardUseRegEx)
 {
@@ -284,38 +43,13 @@ TEST_METHOD(VerifyMatchAllWildcardUseRegEx)
         PWSTR result = nullptr;
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
 }
 
-void VerifyReplaceFirstWildcard(SearchReplaceExpected sreTable[], int tableSize, DWORD flags)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    for (int i = 0; i < tableSize; i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::AreEqual(sreTable[i].expected, result);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceFirstWildCardUseRegex)
-{
-    SearchReplaceExpected sreTable[] = {
-        //search, replace, test, result
-        { L".*", L"Foo", L"AAAAAA", L"Foo" },
-    };
-    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), UseRegularExpressions);
-}
-
 TEST_METHOD(VerifyReplaceFirstWildCardUseRegexMatchAllOccurrences)
 {
     // This differs from the Standard Library: .* has two matches (all and nothing).
@@ -327,27 +61,6 @@ TEST_METHOD(VerifyReplaceFirstWildCardUseRegexMatchAllOccurrences)
     VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), UseRegularExpressions | MatchAllOccurrences);
 }
 
-TEST_METHOD(VerifyReplaceFirstWildCardMatchAllOccurrences)
-{
-    SearchReplaceExpected sreTable[] = {
-        //search, replace, test, result
-        { L".*", L"Foo", L"AAAAAA", L"AAAAAA" },
-        { L".*", L"Foo", L".*", L"Foo" },
-        { L".*", L"Foo", L".*Bar.*", L"FooBarFoo" },
-    };
-    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), MatchAllOccurrences);
-}
-
-TEST_METHOD(VerifyReplaceFirstWildNoFlags)
-{
-    SearchReplaceExpected sreTable[] = {
-        //search, replace, test, result
-        { L".*", L"Foo", L"AAAAAA", L"AAAAAA" },
-        { L".*", L"Foo", L".*", L"Foo" },
-    };
-    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), 0);
-}
-
 TEST_METHOD(VerifyHandleCapturingGroups)
 {
     // This differs from the Standard Library: Boost does not recognize $123 as $1 and "23".
@@ -380,7 +93,8 @@ TEST_METHOD(VerifyHandleCapturingGroups)
         PWSTR result = nullptr;
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
@@ -407,32 +121,11 @@ TEST_METHOD(VerifyLookbehind)
         PWSTR result = nullptr;
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
 }
-
-TEST_METHOD(VerifyEventsFire)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    CMockPowerRenameRegExEvents* mockEvents = new CMockPowerRenameRegExEvents();
-    CComPtr<IPowerRenameRegExEvents> regExEvents;
-    Assert::IsTrue(mockEvents->QueryInterface(IID_PPV_ARGS(&regExEvents)) == S_OK);
-    DWORD cookie = 0;
-    Assert::IsTrue(renameRegEx->Advise(regExEvents, &cookie) == S_OK);
-    DWORD flags = MatchAllOccurrences | UseRegularExpressions | CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"FOO") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"BAR") == S_OK);
-    Assert::IsTrue(renameRegEx->PutFileTime(SYSTEMTIME{0}) == S_OK);
-    Assert::IsTrue(renameRegEx->ResetFileTime() == S_OK);
-    Assert::IsTrue(lstrcmpi(L"FOO", mockEvents->m_searchTerm) == 0);
-    Assert::IsTrue(lstrcmpi(L"BAR", mockEvents->m_replaceTerm) == 0);
-    Assert::IsTrue(flags == mockEvents->m_flags);
-    Assert::IsTrue(renameRegEx->UnAdvise(cookie) == S_OK);
-    mockEvents->Release();
-}
 };
 }
diff --git a/src/modules/powerrename/unittests/PowerRenameRegExTests.cpp b/src/modules/powerrename/unittests/PowerRenameRegExTests.cpp
index aadfb99c1c..eff80bf4cd 100644
--- a/src/modules/powerrename/unittests/PowerRenameRegExTests.cpp
+++ b/src/modules/powerrename/unittests/PowerRenameRegExTests.cpp
@@ -8,14 +8,6 @@ using namespace Microsoft::VisualStudio::CppUnitTestFramework;
 
 namespace PowerRenameRegExTests
 {
-    struct SearchReplaceExpected
-    {
-        PCWSTR search;
-        PCWSTR replace;
-        PCWSTR test;
-        PCWSTR expected;
-    };
-
     TEST_CLASS(SimpleTests){
         public:
 TEST_CLASS_INITIALIZE(ClassInitialize)
@@ -23,241 +15,8 @@ TEST_CLASS_INITIALIZE(ClassInitialize)
     CSettingsInstance().SetUseBoostLib(false);
 }
 
-TEST_METHOD(GeneralReplaceTest)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"big") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"bigbar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceNoMatch)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"notfound") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"big") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"foobar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceNoSearchOrReplaceTerm)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(result == nullptr);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceNoReplaceTerm)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"bar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(ReplaceEmptyStringReplaceTerm)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    PWSTR result = nullptr;
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"foo") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"") == S_OK);
-    Assert::IsTrue(renameRegEx->Replace(L"foobar", &result) == S_OK);
-    Assert::IsTrue(wcscmp(result, L"bar") == 0);
-    CoTaskMemFree(result);
-}
-
-TEST_METHOD(VerifyDefaultFlags)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = 0;
-    Assert::IsTrue(renameRegEx->GetFlags(&flags) == S_OK);
-    Assert::IsTrue(flags == 0);
-}
-
-TEST_METHOD(VerifyCaseSensitiveSearch)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"Foo", L"Foo", L"FooBar", L"FooBar" },
-        { L"Foo", L"boo", L"FooBar", L"booBar" },
-        { L"Foo", L"boo", L"foobar", L"foobar" },
-        { L"123", L"654", L"123456", L"654456" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceFirstOnly)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = 0;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AABBA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABAB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAll)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAllCaseInsensitive)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences | CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
-        { L"b", L"BBB", L"AbABAb", L"ABBBABABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceFirstOnlyUseRegEx)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = UseRegularExpressions;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AABBA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABAB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAllUseRegEx)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences | UseRegularExpressions;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"B", L"BBB", L"ABABAB", L"ABBBABBBABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceAllUseRegExCaseSensitive)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    DWORD flags = MatchAllOccurrences | UseRegularExpressions | CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    SearchReplaceExpected sreTable[] = {
-        { L"B", L"BB", L"ABA", L"ABBA" },
-        { L"B", L"A", L"ABBBA", L"AAAAA" },
-        { L"b", L"BBB", L"AbABAb", L"ABBBABABBB" },
-    };
-
-    for (int i = 0; i < ARRAYSIZE(sreTable); i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
-        CoTaskMemFree(result);
-    }
-}
+#define TESTS_PARTIAL
+#include "CommonRegExTests.h"
 
 TEST_METHOD(VerifyMatchAllWildcardUseRegEx)
 {
@@ -275,38 +34,13 @@ TEST_METHOD(VerifyMatchAllWildcardUseRegEx)
         PWSTR result = nullptr;
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
 }
 
-void VerifyReplaceFirstWildcard(SearchReplaceExpected sreTable[], int tableSize, DWORD flags)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-
-    for (int i = 0; i < tableSize; i++)
-    {
-        PWSTR result = nullptr;
-        Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
-        Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
-        Assert::AreEqual(sreTable[i].expected, result);
-        CoTaskMemFree(result);
-    }
-}
-
-TEST_METHOD(VerifyReplaceFirstWildCardUseRegex)
-{
-    SearchReplaceExpected sreTable[] = {
-        //search, replace, test, result
-        { L".*", L"Foo", L"AAAAAA", L"Foo" },
-    };
-    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), UseRegularExpressions);
-}
-
 TEST_METHOD(VerifyReplaceFirstWildCardUseRegexMatchAllOccurrences)
 {
     SearchReplaceExpected sreTable[] = {
@@ -316,27 +50,6 @@ TEST_METHOD(VerifyReplaceFirstWildCardUseRegexMatchAllOccurrences)
     VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), UseRegularExpressions | MatchAllOccurrences);
 }
 
-TEST_METHOD(VerifyReplaceFirstWildCardMatchAllOccurrences)
-{
-    SearchReplaceExpected sreTable[] = {
-        //search, replace, test, result
-        { L".*", L"Foo", L"AAAAAA", L"AAAAAA" },
-        { L".*", L"Foo", L".*", L"Foo" },
-        { L".*", L"Foo", L".*Bar.*", L"FooBarFoo" },
-    };
-    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), MatchAllOccurrences);
-}
-
-TEST_METHOD(VerifyReplaceFirstWildNoFlags)
-{
-    SearchReplaceExpected sreTable[] = {
-        //search, replace, test, result
-        { L".*", L"Foo", L"AAAAAA", L"AAAAAA" },
-        { L".*", L"Foo", L".*", L"Foo" },
-    };
-    VerifyReplaceFirstWildcard(sreTable, ARRAYSIZE(sreTable), 0);
-}
-
 TEST_METHOD(VerifyHandleCapturingGroups)
 {
     CComPtr<IPowerRenameRegEx> renameRegEx;
@@ -362,7 +75,8 @@ TEST_METHOD(VerifyHandleCapturingGroups)
         PWSTR result = nullptr;
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
@@ -387,7 +101,8 @@ TEST_METHOD (VerifyFileAttributesNoPadding)
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
         Assert::IsTrue(renameRegEx->PutFileTime(fileTime) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
@@ -411,7 +126,8 @@ TEST_METHOD (VerifyFileAttributesPadding)
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
         Assert::IsTrue(renameRegEx->PutFileTime(fileTime) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
@@ -459,7 +175,8 @@ TEST_METHOD (VerifyFileAttributesMonthandDayNames)
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
         Assert::IsTrue(renameRegEx->PutFileTime(fileTime) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == S_OK);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == S_OK);
         Assert::IsTrue(wcscmp(result, sreTable[i].expected) == 0);
         CoTaskMemFree(result);
     }
@@ -483,33 +200,12 @@ TEST_METHOD(VerifyLookbehindFails)
         PWSTR result = nullptr;
         Assert::IsTrue(renameRegEx->PutSearchTerm(sreTable[i].search) == S_OK);
         Assert::IsTrue(renameRegEx->PutReplaceTerm(sreTable[i].replace) == S_OK);
-        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result) == E_FAIL);
+        unsigned long index = {};
+        Assert::IsTrue(renameRegEx->Replace(sreTable[i].test, &result, index) == E_FAIL);
         Assert::AreEqual(sreTable[i].expected, result);
         CoTaskMemFree(result);
     }
 }
 
-TEST_METHOD(VerifyEventsFire)
-{
-    CComPtr<IPowerRenameRegEx> renameRegEx;
-    Assert::IsTrue(CPowerRenameRegEx::s_CreateInstance(&renameRegEx) == S_OK);
-    CMockPowerRenameRegExEvents* mockEvents = new CMockPowerRenameRegExEvents();
-    CComPtr<IPowerRenameRegExEvents> regExEvents;
-    Assert::IsTrue(mockEvents->QueryInterface(IID_PPV_ARGS(&regExEvents)) == S_OK);
-    DWORD cookie = 0;
-    Assert::IsTrue(renameRegEx->Advise(regExEvents, &cookie) == S_OK);
-    DWORD flags = MatchAllOccurrences | UseRegularExpressions | CaseSensitive;
-    Assert::IsTrue(renameRegEx->PutFlags(flags) == S_OK);
-    Assert::IsTrue(renameRegEx->PutSearchTerm(L"FOO") == S_OK);
-    Assert::IsTrue(renameRegEx->PutReplaceTerm(L"BAR") == S_OK);
-    Assert::IsTrue(renameRegEx->PutFileTime(SYSTEMTIME{ 0 }) == S_OK);
-    Assert::IsTrue(renameRegEx->ResetFileTime() == S_OK);
-    Assert::IsTrue(lstrcmpi(L"FOO", mockEvents->m_searchTerm) == 0);
-    Assert::IsTrue(lstrcmpi(L"BAR", mockEvents->m_replaceTerm) == 0);
-    Assert::IsTrue(flags == mockEvents->m_flags);
-    Assert::IsTrue(renameRegEx->UnAdvise(cookie) == S_OK);
-    mockEvents->Release();
-}
-}
-;
+};
 }
diff --git a/src/modules/powerrename/unittests/pch.h b/src/modules/powerrename/unittests/pch.h
index 95c31bcf3f..3ca7e712fb 100644
--- a/src/modules/powerrename/unittests/pch.h
+++ b/src/modules/powerrename/unittests/pch.h
@@ -3,11 +3,4 @@
 #include "targetver.h"
 
 #include <atlbase.h>
-
-// Headers for CppUnitTest
-
-// Suppressing 26466 - Don't use static_cast downcasts - in CppUnitTest.h
-#pragma warning(push)
-#pragma warning(disable : 26466)
-#include "CppUnitTest.h"
-#pragma warning(pop)
+#include "CppUnitTestInclude.h"
\ No newline at end of file