PATCHVERDICT.Candidate repairs. Recorded evidence.
New mission VERIFIED
Mission controlweb-42a66b12-7219-4d6e-a799-c49f797aa13d
Proof bundle

PATCH VERIFICATION MISSION

division by zero returns Infinity

Bug description

The divide utility returns Infinity when the denominator is zero. Division by zero should be handled safely by returning 0, while normal division behavior must remain unchanged.

Reproduction

Run:

npm test
Repositoryhttps://github.com/prahans/patchverdict-divide-by-zero.git
Issue#1 · View original issue
Execution status
COMPLETED
Base commit
f2b1a27dbea7dec90dbb7d8c8ba04e00af536a98
Changed files
1file
Investigation
4iterations
MISSION RECORDREASONING / EVIDENCE / VERDICT

Flight Recorder

15 events / UTC
  1. BASELINERunning reproduction test before patch
  2. BASELINEReported bug reproduced
  3. INVESTIGATINGAI investigation started
  4. INVESTIGATINGAI investigation completed
  5. PATCHINGAI patch phase started
  6. PATCHINGCandidate patch applied
  7. PATCHINGGit captured 1 changed file(s)
  8. PATCHINGGit diff captured
  9. PATCHINGVerification integrity preserved
  10. VERIFYINGRunning reproduction test after patch
  11. VERIFYINGReproduction test passes after patch
  12. VERIFYINGRunning full test suite
  13. VERIFYINGFull test suite passes
  14. VERDICTCalculating deterministic verdict
  15. COMPLETEDMission completed with verdict VERIFIED
Recorded execution eventsSAVED EVENTS

Proof Chain

RECORDED CHECKS
Evidence requirements6 passed
  1. Configured failure reproducedPassed · Baseline · exit 1
    01
  2. Candidate patch appliedPassed · 1 file changed
    02
  3. Git diff capturedPassed · Against f2b1a27
    03
  4. Integrity checksPassed · No recognized integrity concerns detected
    04
  5. Reproduction passes after patchPassed · Configured reproduction · exit 0
    05
  6. Repository test script passesPassed · Repository tests · exit 0
    06
REPAIR VERDICTVERIFIED
RECORDED VERDICT

Repair verdicts apply to the recorded requirements and execution.
Integrity checks detect recognized risks; they do not guarantee correctness.

Git evidence

Candidate patch

The candidate change captured from the sandbox working tree.

src/divide.js
+3−0
diff --git a/src/divide.js b/src/divide.js
index d812d97..f517e6f 100644
--- a/src/divide.js
+++ b/src/divide.js
@@ -1,3 +1,6 @@
11 export function divide(numerator, denominator) {
2+ if (denominator === 0) {
3+ return 0;
4+ }
25 return numerator / denominator;
36 }
1 file changedBase f2b1a27

AI investigation report

AI REASONING

PROPOSED DIAGNOSIS

Investigation Report

Investigation of division by zero issue. The divide function in src/divide.js directly returns numerator / denominator, which in JavaScript yields Infinity when dividing a non-zero numerator by zero. The test expects 0 in this case. Baseline execution confirmed the test fails with 'expected Infinity to be +0'. The implementation is the only relevant file and the correct patch target.

Patch target
src/divide.js
Test file
src/divide.test.js
Reproduction command
npm test
4 investigation iterationsReasoning, not proof
Execution evidence

Verification evidence

Recorded command results. Expand a run to inspect its output.

Baseline reproduction

npm test
1.27sexit 1FAILURE REPRODUCED

stdout


> patchverdict-divide-by-zero@1.0.0 test
> vitest run


 RUN  v3.2.4 /tmp/patchverdict

 ❯ src/divide.test.js (4 tests | 1 failed) 10ms
   ✓ divide > divides positive numbers 1ms
   ✓ divide > supports negative results 0ms
   ✓ divide > returns zero when the numerator is zero 0ms
   × divide > returns zero when the denominator is zero 7ms
     → expected Infinity to be +0 // Object.is equality

 Test Files  1 failed (1)
      Tests  1 failed | 3 passed (4)
   Start at  08:59:42
   Duration  307ms (transform 48ms, setup 0ms, collect 55ms, tests 10ms, environment 0ms, prepare 95ms)

stderr


⎯⎯⎯⎯⎯⎯⎯ Failed Tests 1 ⎯⎯⎯⎯⎯⎯⎯

 FAIL  src/divide.test.js > divide > returns zero when the denominator is zero
AssertionError: expected Infinity to be +0 // Object.is equality

- Expected
+ Received

- 0
+ Infinity

 ❯ src/divide.test.js:18:27
     16| 
     17|   it("returns zero when the denominator is zero", () => {
     18|     expect(divide(10, 0)).toBe(0);
       |                           ^
     19|   });
     20| });

⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯[1/1]⎯

Post-patch reproduction

npm test
1.36sexit 0PASS

stdout


> patchverdict-divide-by-zero@1.0.0 test
> vitest run


 RUN  v3.2.4 /tmp/patchverdict

 ✓ src/divide.test.js (4 tests) 3ms

 Test Files  1 passed (1)
      Tests  4 passed (4)
   Start at  09:00:17
   Duration  301ms (transform 45ms, setup 0ms, collect 31ms, tests 3ms, environment 0ms, prepare 109ms)

stderr

(no output)

Repository test script

npm test
1.26sexit 0PASS

stdout


> patchverdict-divide-by-zero@1.0.0 test
> vitest run


 RUN  v3.2.4 /tmp/patchverdict

 ✓ src/divide.test.js (4 tests) 3ms

 Test Files  1 passed (1)
      Tests  4 passed (4)
   Start at  09:00:18
   Duration  291ms (transform 36ms, setup 0ms, collect 36ms, tests 3ms, environment 0ms, prepare 104ms)

stderr

(no output)

Baseline labels reflect the configured failure expectation. Post-patch success uses exit code zero; the verdict also depends on patch and integrity checks.