task/completion/zsh/_task

#compdef task
#
# Thin wrapper around `task __complete`. All suggestion logic lives in the
# Go engine — do not add completion logic here.

TASK_CMD="${TASK_EXE:-task}"

_task() {
	local -a args lines completions opts ctl
	local output directive line

	# Completion directives, mirroring internal/complete/complete.go.
	local -ri NO_SPACE=2 NO_FILE_COMP=4 FILTER_FILE_EXT=8 FILTER_DIRS=16 KEEP_ORDER=32

	# Map the zsh completion zstyles to engine flags. `-T` is true when the
	# style is unset (its default) or explicitly true, so a flag is only passed
	# when the user turned the style off.
	zstyle -T ":completion:${curcontext}:" show-aliases || ctl+=(--no-aliases)
	zstyle -T ":completion:${curcontext}:" verbose      || ctl+=(--no-descriptions)

	# (@) preserves a trailing empty string, which the engine relies on to
	# know the cursor is on a fresh word.
	args=("${(@)words[2,CURRENT]}")
	(( ${#args} == 0 )) && args=("")

	output=$("$TASK_CMD" __complete "${ctl[@]}" "${args[@]}" 2>/dev/null)
	if [[ -z "$output" ]]; then
		_files
		return
	fi

	lines=("${(f)output}")
	directive="${lines[-1]#:}"
	lines=("${(@)lines[1,-2]}")

	if (( directive & FILTER_FILE_EXT )); then
		local -a globs
		for line in "${lines[@]}"; do
			globs+=("*.${line}")
		done
		_files -g "(${(j:|:)globs})"
		return
	fi

	if (( directive & FILTER_DIRS )); then
		_path_files -/
		return
	fi

	# `:` inside the value must be escaped: _describe splits on the first
	# unescaped colon (e.g. "docs:serve" would otherwise become value "docs").
	local value desc
	for line in "${lines[@]}"; do
		if [[ "$line" == *$'\t'* ]]; then
			value="${line%%$'\t'*}"
			desc="${line#*$'\t'}"
			completions+=("${value//:/\\:}:$desc")
		else
			completions+=("${line//:/\\:}")
		fi
	done

	(( directive & NO_SPACE ))  && opts+=(-S '')
	(( directive & KEEP_ORDER )) && opts+=(-V)

	if (( ${#completions} > 0 )); then
		_describe -t tasks 'task' completions "${opts[@]}"
	fi

	(( directive & NO_FILE_COMP )) && return
	_files
}

compdef _task "$TASK_CMD"