libc/stdio: add stdio indicator test

[lukkrusz]

Description

Motivation and Context

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (refactoring, style fixes, git/CI config, submodule management, no code logic changes)

How Has This Been Tested?

• Already covered by automatic testing.
• New test added: (add PR link here).
• Tested by hand on: (list targets here).

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing linter checks and tests passed.
• My changes generate no new compilation warnings for any of the targets.

Special treatment

• This PR needs additional PRs to work (list the PRs, preferably in merge-order).
• I will merge this PR by myself when appropriate.

Previous conversation: #295

[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the test coverage for standard I/O (stdio) functions within the libc library. It introduces a dedicated test module to rigorously validate the behavior of file indicator functions like feof, ftell, and ftello, as well as the getdelim function for delimited input. The changes aim to improve the robustness and reliability of these core library components by testing them across a wide range of conditions, including different file modes, empty/non-empty files, error handling, and non-seekable stream types.

Highlights

• New Test File: A new test file, libc/stdio/stdio_indicator.c, has been added to the libc-tests suite.
• Expanded stdio Test Coverage: Comprehensive test cases for feof, ftell, ftello, and getdelim functions have been introduced, covering various scenarios and edge cases.
• Test Group Registration: The main test runner in libc/stdio/main.c has been updated to include the newly added test groups for stdio_feof, stdio_ftell, and stdio_getdelim.

Changelog

• libc/stdio/main.c
  • Added RUN_TEST_GROUP calls for stdio_feof, stdio_ftell, and stdio_getdelim to the test runner.
• libc/stdio/stdio_indicator.c
  • Introduced a new test file stdio_indicator.c.
  • Implemented tests for feof covering various file modes, empty/non-empty files, errno preservation, and error conditions.
  • Implemented tests for ftell and ftello verifying correct position reporting, handling of bad file descriptors, and non-seekable streams (sockets, pipes, fifos).
  • Included tests for getdelim covering delimiter handling, reallocation, invalid arguments, and write-only files.

Activity

• The pull request references a previous conversation at K arkadiusz/stdio indicator test #295, indicating a continuation of work or discussion from an earlier PR.

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[gemini-code-assist]

Code Review

This pull request adds new tests for feof, ftell, and getdelim stdio functions. The changes are good and increase test coverage. I've found a few issues, including resource leaks, a bug in a test assertion, and some areas for improvement in terms of code clarity and efficiency. Please see my detailed comments.

[github-actions]

Unit Test Results

9 773 tests  +220   9 172 ✅ +211   53m 58s ⏱️ + 1m 31s
  591 suites ±  0     601 💤 +  9 
    1 files   ±  0       0 ❌ ±  0 

Results for commit 0e15d8e. ± Comparison against base commit 6ed92c4.

♻️ This comment has been updated with latest results.