Mutation coverage: FMT-nonScientific

[thedavidmeister]

Mutation run on _toNonScientific (src/lib/format/LibFormatDecimalFloat.sol) at 886ca07, mutants M14-M35 (M01-M13 killed in an earlier run). The existing suite killed 21 of 22. The survivor was M34, which drops the mstore(cursor, 0) that clears the bytes after the string in its last word. The existing memory checks only hit branches whose copies leave those bytes zero. The new case -15e2 goes through the trailing-zero fill, which writes a whole word of ASCII 0 past the end, so the padding check fails under M34.

QA

• Discriminating tests: testFormatMemoryNonScientificTrailingZeros - fails under M34 (mutation-probe --only M34: KILLED by this test alone, after the existing suite let M34 survive), passes on base
• Mutations applied: M14-M35 via mutation-probe, scoped with --mc to LibFormatDecimalFloatToDecimalStringTest, LibFormatDecimalFloatMemoryTest, LibDecimalFloatFormatParsePr321EquivalenceTest and LibDecimalFloatExoticFloatTest, excluding testMainEquivalenceDivFloorExamples, testMulRevertsOnlyExponentOverflowEdges, testLog10GridMonotone and testPow10Grid0-3 (out of gas on 886ca07, being fixed separately). 21 killed by existing tests; mstore(cursor, 0) removed -> padding check -> testFormatMemoryNonScientificTrailingZeros
• Oracle: exact maths, -15 × 10^2 = -1500, plus the memory contract stated in the test contract's NatSpec (the string's last word is zero past its length)
• Category check: n/a, no issue; test-only change pinning the uncovered padding-clear behaviour of the non-scientific formatter

🤖 Generated with Claude Code

Summary by CodeRabbit

• Tests
  • Added a regression test for formatting a negative whole number with trailing zeros.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

• Configuration used: Organization UI
• Review profile: ASSERTIVE
• Plan: Advanced
• Run ID: 56cda0e8-0105-4773-a605-ec67a97ba472

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📥 Commits

Reviewing files that changed from the base of the PR and between 886ca07 and 5d507a2.

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📒 Files selected for processing (1)

• test/src/lib/format/LibFormatDecimalFloat.memory.t.sol

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Walkthrough

Adds a memory-formatting regression test. The test formats -15 at exponent 2 without scientific notation and expects -1500.

Changes

Decimal float formatting

Layer / File(s)	Summary
Memory-format regression test test/src/lib/format/LibFormatDecimalFloat.memory.t.sol	Adds a test that checks the output -1500 and documents the zero-fill padding case.

Priority: ⬇️ Low

Estimated code review effort: 1 (Trivial) | ~3 minutes

Change: Other

Merge Risk: ⚪ Minimal · up to 5d507

This adds a regression check for -1500 formatting and cleared string padding; no merge-blocking risk is evident.

Pre-merge checks | 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check		Check skipped - CodeRabbit’s high-level summary is enabled.
Title check		The title clearly identifies the change as mutation-coverage work for the non-scientific formatting path. This matches the added regression test for _toNonScientific and mutation M34.
Docstring Coverage		No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

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