Fix resolving forward refs in generic aliases when ref type is not imported

[Borda]

What does this PR do?

This pull request addresses an issue with resolving forward references in generic type aliases, particularly when the referenced type is not imported into the module where the alias is used. The update ensures that such forward references are correctly resolved by tracing the origin module of the alias. Additionally, a regression test is added to verify this behavior.

Forward reference resolution improvements

• Enhanced the logic in jsonargparse/_postponed_annotations.py to resolve string-based forward references in generic aliases (e.g., list["ForwardReferenced"]) by searching for missing types in the module where the alias was originally defined, not just the current module. This fixes cases where the forward-referenced type is not imported into the using module. [1] [2] [3]
• Updated the changelog to document the fix for resolving forward references in generic aliases when the forward-referenced type is not imported in the using module.

Testing

• Added a regression test (test_add_class_arguments_cross_module_forward_ref_708) to ensure that forward references in generic aliases are resolved correctly, even when the referenced type is not directly imported in the module where the alias is used.

Before submitting

• Did you read the contributing guideline?
• Did you update the documentation? (readme and public docstrings)
• Did you write unit tests such that there is 100% coverage on related code? (required for bug fixes and new features)
• Did you verify that new and existing tests pass locally?
• Did you make sure that all changes preserve backward compatibility?
• Did you update the CHANGELOG including a pull request link? (not for typos, docs, test updates, or minor internal changes/refactors)

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closes #708
cc: @mauvilsa

[Copilot]

Pull request overview

This PR fixes evaluation of postponed annotations when a generic alias contains a string forward reference (e.g. list["ForwardReferenced"]) and the referenced type isn’t imported into the module where the alias is used.

Changes:

• Resolve str forward refs nested in generic alias __args__ during forward-ref resolution.
• Enrich get_type_hints global namespace by locating missing forward-ref targets from the module that originally defined the imported generic alias.
• Add a regression test for the cross-module forward-ref scenario and document the fix in the changelog.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 3 comments.

File	Description
jsonargparse/_postponed_annotations.py	Adds global-namespace enrichment to resolve missing forward-ref targets for imported generic aliases.
jsonargparse_tests/test_postponed_annotations.py	Adds regression test reproducing issue #708 via dynamically created/imported modules.
CHANGELOG.rst	Documents the fix under the current release notes.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (036294a) to head (a033d49).

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #871   +/-   ##
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  Coverage   100.00%   100.00%           
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  Files           25        25           
  Lines         7398      7468   +70     
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+ Hits          7398      7468   +70     

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[Copilot]

Pull request overview

Improves evaluation of postponed annotations by resolving string-based forward references nested inside generic aliases even when the referenced type isn’t imported in the consuming module (regression fix for #708).

Changes:

• Extend forward-ref resolution to handle str entries inside __args__ (e.g., list["ForwardReferenced"]).
• Add global-scope enrichment logic to locate missing forward-referenced types from the module that defined the generic alias.
• Add regression tests for cross-module generic-alias forward refs; document the fix in the changelog; update .gitignore.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 2 comments.

File	Description
jsonargparse/_postponed_annotations.py	Adds logic to discover and inject missing forward-ref targets into get_type_hints globals and resolves string forward refs inside generic alias args.
jsonargparse_tests/test_postponed_annotations.py	Adds regression tests covering cross-module import scenarios and non-module entries in sys.modules.
CHANGELOG.rst	Notes the #708 fix under the next unreleased patch version.
.gitignore	Adds IDE and local tooling artifacts to ignore list.

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[Copilot]

Pull request overview

This PR improves evaluation of postponed type annotations by resolving string forward references inside generic aliases (e.g., list["ForwardReferenced"]) even when the forward-referenced type is not imported in the consuming module, addressing issue #708.

Changes:

• Extend resolve_forward_refs to resolve str entries found in __args__ (not only ForwardRef).
• Add _enrich_globals_for_string_forward_refs with a trigger-to-module cache to locate missing forward-ref types from the alias origin module via sys.modules.
• Add regression tests covering direct/indirect/aliased imports and cache behavior; update changelog and .gitignore.

Reviewed changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 3 comments.

File	Description
jsonargparse/_postponed_annotations.py	Adds logic to resolve string forward refs in generic aliases and attempts to enrich globals by tracing alias origin modules.
jsonargparse_tests/test_postponed_annotations.py	Adds regression tests for #708 and targeted tests for globals enrichment and cache reuse/fallback behavior.
CHANGELOG.rst	Documents the #708 fix under the next unreleased patch version.
.gitignore	Adds IDE/tooling and local environment ignore entries.

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[Borda]

@mauvilsa updated with latest main, as rebase :)

[mauvilsa]

Some weeks ago I tried an agent to fix #708, and even though it worked, I had some concerns. I am not sure if this fix has the same issues. I will analyze and get back to you.