Add line diff tracking to PR line counter workflow

[Copilot]

Extends the PR line counter workflow to calculate and display line changes between PR and base branches.

Changes

• Line difference calculation: Fetch base branch, count lines in base version, compute diff (PR lines - base lines)
• Enhanced output: Display base line count, line diff with directional indicators (📈 increase / 📉 decrease / ➡️ no change) in both GitHub summary and PR comments
• New file handling: When file doesn't exist in base, show "0 (new file)" and full line count as positive diff
• Concurrency safety: Use mktemp for temporary files to avoid conflicts in parallel workflow runs
• Robust error handling: Explicit error checking for base branch fetch with clear error messages
• Resource cleanup: Use trap to ensure temporary files are cleaned up even on unexpected exits

Example Output

Existing file modified:

**Total Lines:** 960
**Base Lines:** 956
**Change:** +4 lines 📈

New file added:

**Total Lines:** 100
**Base Lines:** 0 (new file)
**Change:** +100 lines 📈

Original prompt

---

This section details on the original issue you should resolve

<issue_title>line diff workflow CI</issue_title>
<issue_description>extend .github/workflows/pr-line-counter.yml github action CI such that it will print on github summary & comment the line number change also</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes InferenceMAX/InferenceMAX#164

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[github-actions]

📊 Line Count Report

File: utils/matrix-logic/generate_sweep_configs.py

Total Lines: 956

Base Lines: 956

Change: No change ➡️

[github-actions]

📊 Line Count Report

File: utils/matrix-logic/generate_sweep_configs.py

Total Lines: 956

Base Lines: 956

Change: No change ➡️

[Copilot]

Pull Request Overview

This PR extends the PR line counter workflow to track and display line differences between the PR branch and the base branch. It adds functionality to fetch the base branch version of the target file, calculate the difference in line counts, and display this information with visual indicators.

• Adds base branch file fetching and line counting capability
• Calculates and displays line differences with directional indicators (📈/📉/➡️)
• Handles new files by showing "0 (new file)" for base count

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[Copilot]

The temporary file is created unconditionally but only cleaned up inside conditional branches. If the script exits unexpectedly between line 44 and the cleanup points (lines 53, 59), the temporary file will leak. Consider using a trap to ensure cleanup or move mktemp inside the conditional after verifying the file exists.

[functionstackx]

@copilot apply changes based on this feedback

[Copilot]

Added a trap to ensure the temporary file is cleaned up on exit, even if the script exits unexpectedly. The trap automatically handles cleanup, so the manual rm -f calls have been removed. Fixed in commit ab2df03.

[github-actions]

📊 Line Count Report

File: utils/matrix-logic/generate_sweep_configs.py

Total Lines: 956

Base Lines: 956

Change: No change ➡️

[github-actions]

📊 Line Count Report

File: utils/matrix-logic/generate_sweep_configs.py

Total Lines: 956

Base Lines: 956

Change: No change ➡️

[github-actions]

📊 Line Count Report

File: utils/matrix-logic/generate_sweep_configs.py

Total Lines: 956

Base Lines: 956

Change: No change ➡️

[github-actions]

📊 Line Count Report

File: utils/matrix-logic/generate_sweep_configs.py

Total Lines: 956

Base Lines: 956

Change: No change ➡️