diffguard-domain/preprocess.rs:304: sanitize_line() is 465 lines — clippy::too_many_lines

[EffortlessSteven]

Preprocess::sanitize_line() at crates/diffguard-domain/src/preprocess.rs:304 is 465 lines (limit: 100).

Clippy warning:

warning: this function has too many lines (465/100)
   --> crates/diffguard-domain/src/preprocess.rs:304:5
    |
304 |     pub fn sanitize_line(\&mut self, line: &str) -> String {
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

This function handles masking comments and strings across multiple language syntaxes and is one of the largest functions in the workspace. It should be decomposed into smaller, focused helper methods (e.g., separate masked-comment and masked-string helpers, or per-language handlers).

[EffortlessSteven]

Test Reviewer Findings — work-9dbac498

Coverage Assessment: needs-more

The red tests provide handler-existence checks that confirm the handler methods will be extracted, but they have weak behavioral assertions. Most tests only verify that a handler method can be called without crashing — they don't verify the handler actually produces correct output, transitions modes correctly, or preserves invariants.

What's Covered Well

• Handler method signatures: Tests correctly call each handler with the spec-defined signature
• Output length preservation: test_sanitize_line_preserves_output_length strongly verifies the key invariant
• Multi-line state continuity: Tests verify mode persists across multiple sanitize_line calls
• Handler non-existence confirmed: Compilation fails with E0599: no method named 'handle_normal_mode' found and similar for all 12 handlers

Gaps Found

1. Handler tests lack behavioral assertions: Most handler tests only verify existence, not behavior
2. test_sanitize_line_is_dispatch_loop line-counting is fragile: Brace-matching algorithm could fail on nested structs
3. Rust 2021 raw string literal issues: Strings containing # conflict with raw string prefix syntax
4. Missing #[inline] verification: No test verifies this attribute is present on small handlers
5. handle_normal_mode delegation not tested: No test verifies it delegates to sub-handlers

What Needs Fixing

1. Fix Rust 2021 raw string literal issues in test code
2. Strengthen handler behavioral tests with assertions on self.mode transitions and out bytes
3. Make line-counting test more robust

Test Run Confirmation

Tests FAIL to compile with expected handler-not-found errors (E0599). Additionally, there are Rust 2021 string literal bugs that need fixing.

Sufficiency Verdict

needs-more — Handler existence is verified, but most handler tests are pure existence checks without behavioral assertions.