## Summary of the Pull Request
Show timestamp, HRESULT (hex/decimal), and full Exception.ToString() in
the error message. Centralize message generation in a helper class for
consistency.
Example:
```
============================================================
😢 An unexpected error occurred in the 'Open' extension.
Summary:
Message: Operation is not valid due to the current state of the object. (inferred from HRESULT 0x80131509)
Type: System.Runtime.InteropServices.COMException
Source: WinRT.Runtime
Time: 2025-08-07 15:54:20.4189499
HRESULT: 0x80131509 (-2146233079)
Stack Trace:
at WinRT.ExceptionHelpers.<ThrowExceptionForHR>g__Throw|38_0(Int32 hr)
at ABI.Microsoft.CommandPalette.Extensions.IListPageMethods.GetItems(IObjectReference _obj)
at Microsoft.CmdPal.Core.ViewModels.ListViewModel.FetchItems()
at Microsoft.CmdPal.Core.ViewModels.ListViewModel.InitializeProperties()
at Microsoft.CmdPal.Core.ViewModels.PageViewModel.InitializeAsync()
------------------ Full Exception Details ------------------
System.Runtime.InteropServices.COMException (0x80131509)
at WinRT.ExceptionHelpers.<ThrowExceptionForHR>g__Throw|38_0(Int32 hr)
at ABI.Microsoft.CommandPalette.Extensions.IListPageMethods.GetItems(IObjectReference _obj)
at Microsoft.CmdPal.Core.ViewModels.ListViewModel.FetchItems()
at Microsoft.CmdPal.Core.ViewModels.ListViewModel.InitializeProperties()
at Microsoft.CmdPal.Core.ViewModels.PageViewModel.InitializeAsync()
ℹ️ If you need further assistance, please include this information in your support request.
ℹ️ Before sending, take a quick look to make sure it doesn't contain any personal or sensitive information.
============================================================
```
<!-- Please review the items on the PR checklist before submitting-->
## PR Checklist
- [x] Closes: #41034
- [ ] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [ ] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx
<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments
## Validation Steps Performed
I crashed an extension on purpose and read the message.
What the title says. 😄
Rather than relying on the potentially overloaded `!=` or `==` operators
when checking for null, now we'll use the `is` expression (possibly
combined with the `not` operator) to ensure correct checking. Probably
overkill for many of these classes, but decided to err on the side of
consistency. Would matter more on classes that may be inherited or
extended.
Using `is` and `is not` will provide us a guarantee that no
user-overloaded equality operators (`==`/`!=`) is invoked when a
`expression is null` is evaluated.
In code form, changed all instances of:
```c#
something != null
something == null
```
to:
```c#
something is not null
something is null
```
The one exception was checking null on a `KeyChord`. `KeyChord` is a
struct which is never null so VS will raise an error when trying this
versus just providing a warning when using `keyChord != null`. In
reality, we shouldn't do this check because it can't ever be null. In
the case of a `KeyChord` it **would** be a `KeyChord` equivalent to:
```c#
KeyChord keyChord = new ()
{
Modifiers = 0,
Vkey = 0,
ScanCode = 0
};
```
_targets #40504_
Major refactoring for #40113
This moves a large swath of the codebase to a `.Core` project. "Core"
doesn't have any explicit dependencies on "extensions", settings or the
current `MainListPage`. It's just a filterable list of stuff. This
should let us make this component a bit more reusable.
This is half of a PR. As I did this, I noticed a particular bit of code
for TopLevelVViewModels and CommandPaletteHost that was _very rough_.
Solving it in this PR would make "move everything to a new project" much
harder to review. So I'm submitting two PRs simultaneously, so we can
see the changes separately, then merge together.
