⚒️ Forge: Refactor repetitive compare_field calls in diff_config.rs

[madmax983]

• 🚬 Smell: Repetitive block of compare_field with 8 arguments, duplicating paths and variables across 18 calls.
• ✨ Solution: Abstracted the call into cmp_manifest and cmp_limits closures to simplify field comparisons.
• 🧼 Benefit: Reduces boilerplate significantly, making the run method readable.
• 🛡️ Verification: Cargo formatting, clippy and tests passed. No logic change.

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PR created automatically by Jules for task 16519351247515352404 started by @madmax983

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[gemini-code-assist]

Code Review

This pull request refactors src/run/diff_config.rs to reduce boilerplate by introducing local closures (cmp_manifest and cmp_limits) for comparing manifest and limit fields. The reviewer suggests further simplifying the code: first, by replacing the cmp_manifest closure with a macro (cmp_manifest!) to avoid passing mutable vector references on every call; and second, by capturing the mutable vectors directly within the cmp_limits closure since they are used in a single contiguous block.

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[gemini-code-assist]

Instead of a closure that requires passing compared_fields, changed_fields, and ignored_fields as arguments in every single call (due to borrow checker limitations across intermissions), we can define a macro cmp_manifest!. This allows direct access to the variables in the outer scope without passing them, significantly reducing boilerplate.

    macro_rules! cmp_manifest {
        ($group:expr, $field:expr) => {
            compare_field(
                $group,
                &format!(".{}", $field),
                &get_field_val(&baseline_manifest, &[$group, $field]),
                &get_field_val(&candidate_manifest, &[$group, $field]),
                &mut compared_fields,
                &mut changed_fields,
                &mut ignored_fields,
                &ignore_patterns,
            );
        };
    }

[gemini-code-assist]

Use the newly defined cmp_manifest! macro to simplify the field comparisons for harness and dataset.

    cmp_manifest!("harness", "name");
    cmp_manifest!("harness", "version");
    cmp_manifest!("harness", "git_sha");
    cmp_manifest!("harness", "git_dirty");

    // 2. dataset
    cmp_manifest!("dataset", "path");
    cmp_manifest!("dataset", "sha256");
    cmp_manifest!("dataset", "instance_count");

[gemini-code-assist]

Use the newly defined cmp_manifest! macro to simplify the field comparisons for prompt_template and model.

    cmp_manifest!("prompt_template", "source");
    cmp_manifest!("prompt_template", "path");
    cmp_manifest!("prompt_template", "sha256");

    // 4. model
    cmp_manifest!("model", "name");
    cmp_manifest!("model", "backend");
    cmp_manifest!("model", "backend_version");
    cmp_manifest!("model", "base_url");

[gemini-code-assist]

Since cmp_limits is defined and used within a single contiguous block with no other intervening borrows of compared_fields, changed_fields, or ignored_fields, we can simplify the closure by capturing these variables mutably from the outer scope. This eliminates the need to pass them as arguments in every call.

    let mut cmp_limits = |field: &str| {
        let path = format!(".{field}");
        compare_field(
            "limits",
            &path,
            &get_field_val(&base_limits, &[field]),
            &get_field_val(&cand_limits, &[field]),
            &mut compared_fields,
            &mut changed_fields,
            &mut ignored_fields,
            &ignore_patterns,
        );
    };

    cmp_limits("step_limit");
    cmp_limits("per_task_budget_usd");
    cmp_limits("task_timeout_secs");
    cmp_limits("sweep_cost_limit_usd");

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.40%. Comparing base (e98c81c) to head (e055971).

Additional details and impacted files

@@            Coverage Diff             @@
##            trunk     #625      +/-   ##
==========================================
- Coverage   85.40%   85.40%   -0.01%     
==========================================
  Files         116      116              
  Lines       67035    67021      -14     
==========================================
- Hits        57250    57236      -14     
  Misses       9785     9785              

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