fix: replace size compute

[SyMind]

No description provided.

[codspeed-hq]

CodSpeed Performance Report

Merging #204 will improve performances by ×5

_{Comparing fix-replace-size (3c1808d) with main (aea29de)}

Summary

⚡ 2 improvements
✅ 9 untouched
⏩ 6 skipped¹

Benchmarks breakdown

	Benchmark	BASE	HEAD	Change
⚡	complex_replace_source_map_cached_source_stream_chunks	36.5 ms	7.4 ms	×5
⚡	repetitive_react_components_map	2.4 ms	2 ms	+19.25%

Footnotes

1. 6 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[Copilot]

Pull Request Overview

This PR fixes a bug in the size() method of ReplaceSource where replacements that start beyond the source bounds were causing incorrect size calculations. The fix adds an early check to handle out-of-bounds replacements by simply adding their content length to the total size.

Key Changes:

• Added a boundary check in the size() method to detect and handle replacements that start beyond the inner source size
• Added a test case with an out-of-bounds replacement to verify the fix works correctly

Comments suppressed due to low confidence (1)

src/replace_source.rs:223

• The current fix handles replacements that start entirely beyond the source bounds, but it doesn't handle the case where a replacement starts within bounds but extends beyond them (i.e., replacement.start < inner_source_size but replacement.end > inner_source_size).

For example, if the source is 1070 bytes and we have a replacement from position 1000 to 2000, the current code calculates:

• original_length = 2000 - 1000 = 1000 (line 220-223)
• But the actual original content is only 70 bytes (from 1000 to 1070)

This causes the size calculation to be incorrect because it subtracts the full 1000 bytes instead of just 70 bytes.

Consider clamping the replacement.end to inner_source_size when calculating original_length:

let original_length = replacement
  .end
  .min(inner_source_size as u32)  // Clamp to source size
  .saturating_sub(replacement.start.max(inner_pos))
  as usize;

      let original_length = replacement
        .end
        .saturating_sub(replacement.start.max(inner_pos))
        as usize;

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