Enhance cache-dependency-path handling to support files outside the workspace root

[aparnajyothi-y]

Description:
This PR enhances cacheDependencies in setup-python to properly handle cases where the cache-dependency-path file is located outside the workspace root also.

Related issue:
#476
#361

Check list:

[ X ] Mark if documentation changes are required.
[ X ] Mark if tests were added or updated to cover the changes.

[Copilot]

Pull Request Overview

Enhance the cacheDependencies action to support dependency files located outside the workspace by copying them into the workspace root before caching.

• Exported cacheDependencies and added logic to resolve, copy, and log external dependency files.
• Updated documentation to note support for external paths.
• Added unit tests covering file copying, missing file warnings, and copy errors.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
src/setup-python.ts	Exported cacheDependencies, added resolution and copy logic for external cache-dependency-path.
docs/advanced-usage.md	Added note about external-path support for cache-dependency-path.
tests/setup-python.test.ts	Added tests for copying dependencies, missing files, copy failures, and skipping when no input.

Comments suppressed due to low confidence (2)

src/setup-python.ts:67

• The code computes resolvedDependencyPath but still passes the original cacheDependencyPath to getCacheDistributor, so the distributor won’t use the copied file location. Consider passing resolvedDependencyPath (or falling back to cacheDependencyPath) as the dependency-path argument.

const cacheDistributor = getCacheDistributor(

tests/setup-python.test.ts:59

• Add a test case for when cache-dependency-path points to a file already inside the workspace (sourcePath === targetPath) to ensure the logic skips copying but still sets the resolved path correctly.

it('copies the dependency file and resolves the path with directory structure', async () => {