Add unit test for surface.convert_alpha argument check (#599)

[sudeeps-projects]

Hi! This PR adds an automated unit test to verify the behavior of surface.convert_alpha when passed an explicit surface argument. It ensures the framework safely processes the parameter format without crashing and behaves identically to an empty parameter call. Closes #599.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

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Reviewing files that changed from the base of the PR and between 31d6b5b and 32a552a.

📒 Files selected for processing (1)

• test/surface_test.py

🚧 Files skipped from review as they are similar to previous changes (1)

• test/surface_test.py

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📝 Walkthrough

Walkthrough

The test suite adds regression coverage for Surface.convert_alpha(target_surface). It initializes a hidden display, suppresses the expected deprecation warning, compares surface formats and boundary pixels, and ensures display cleanup.

Changes

Surface alpha conversion

Layer / File(s)	Summary
Target-surface conversion coverage test/surface_test.py	Adds a test that compares target-surface conversion with default conversion. The test checks size, flags, bit depth, boundary pixels, warning handling, and display cleanup.

Estimated code review effort: 2 (Simple) | ~10 minutes

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Linked Issues check	⚠️ Warning	The linked issue concerns character origin coordinates, but this pull request tests surface.convert_alpha argument handling.	Link the pull request to an issue about surface.convert_alpha, or update the implementation and tests to satisfy issue #599.
Out of Scope Changes check	⚠️ Warning	The convert_alpha test is unrelated to the linked issue's character-origin requirements.	Remove the unrelated test or provide a correctly scoped linked issue for the surface.convert_alpha behavior.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the added unit test and the surface.convert_alpha argument under test.
Description check	✅ Passed	The description accurately explains the convert_alpha regression test and its expected behavior.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

🧹 Nitpick comments (1)

test/surface_test.py (1)

983-998: 🎯 Functional Correctness | 🔵 Trivial | ⚡ Quick win

Strengthen the regression assertion.

base_surf and target_surf use the same format. The assertions compare only size and flags. A regression that changes pixel data or incorrectly uses the target format can pass.

Use a target surface with a different format. Fill base_surf with non-default RGBA data. Compare pixel content and relevant format metadata between both results.

Suggested test improvement

             base_surf = pygame.Surface((10, 10), pygame.SRCALPHA)
-            target_surf = pygame.Surface((10, 10), pygame.SRCALPHA)
+            base_surf.fill((17, 34, 51, 127))
+            target_surf = pygame.Surface((10, 10), 0, 16)

             self.assertIsInstance(res_with_arg, pygame.Surface)
             self.assertEqual(res_no_arg.get_size(), res_with_arg.get_size())
             self.assertEqual(res_no_arg.get_flags(), res_with_arg.get_flags())
+            self.assertEqual(res_no_arg.get_bitsize(), res_with_arg.get_bitsize())
+            for point in ((0, 0), (9, 9)):
+                self.assertEqual(res_no_arg.get_at(point), res_with_arg.get_at(point))

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@test/surface_test.py` around lines 983 - 998, Strengthen the convert_alpha
regression test around base_surf and target_surf by creating the target with a
different pixel format, filling base_surf with non-default RGBA data, and
comparing the resulting pixel content plus relevant format metadata. Retain the
existing size and flags checks and warning suppression, ensuring
convert_alpha(target_surf) matches the no-argument result rather than adopting
the target format or altering pixels.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Nitpick comments:
In `@test/surface_test.py`:
- Around line 983-998: Strengthen the convert_alpha regression test around
base_surf and target_surf by creating the target with a different pixel format,
filling base_surf with non-default RGBA data, and comparing the resulting pixel
content plus relevant format metadata. Retain the existing size and flags checks
and warning suppression, ensuring convert_alpha(target_surf) matches the
no-argument result rather than adopting the target format or altering pixels.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

Review profile: CHILL

Plan: Pro Plus

Run ID: 3b730f3b-1d5b-4316-bbce-9413df93d103

📥 Commits

Reviewing files that changed from the base of the PR and between d194055 and 31d6b5b.

📒 Files selected for processing (1)

• test/surface_test.py

[sudeeps-projects]

Hi, I have strengthened convert_alpha regression test assertions as per review

[shaurya-sharma-dev]

Not a maintainer, but I think you have a typo in your PR description. Issue #599 is a completely unrelated issue that relates to pygame.font.Font, while your PR is dealing with pygame.Surface.