PATCHVERDICT.Candidate repairs. Recorded evidence.
New mission VERIFIED
Mission controlweb-d8fe1d8a-638f-4b06-9a40-e591791d7379
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

Investigated the reported 'division by zero returns Infinity' bug. Inspected src/divide.js and src/divide.test.js. The divide function directly returns numerator / denominator without handling zero denominator, causing JavaScript to return Infinity. The test suite expects 0 when denominator is zero, and the targeted test run confirmed the same failure (Infinity vs 0).

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
1.07sexit 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) 12ms
   ✓ 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 10ms
     → expected Infinity to be +0 // Object.is equality

 Test Files  1 failed (1)
      Tests  1 failed | 3 passed (4)
   Start at  14:47:31
   Duration  254ms (transform 57ms, setup 0ms, collect 30ms, tests 12ms, environment 0ms, prepare 92ms)

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
1.19sexit 0PASS

stdout


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


 RUN  v3.2.4 /tmp/patchverdict

 ✓ src/divide.test.js (4 tests) 2ms

 Test Files  1 passed (1)
      Tests  4 passed (4)
   Start at  14:47:56
   Duration  289ms (transform 39ms, setup 0ms, collect 52ms, tests 2ms, environment 0ms, prepare 93ms)

stderr

(no output)

Repository test script

npm test
1.02sexit 0PASS

stdout


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


 RUN  v3.2.4 /tmp/patchverdict

 ✓ src/divide.test.js (4 tests) 2ms

 Test Files  1 passed (1)
      Tests  4 passed (4)
   Start at  14:47:58
   Duration  246ms (transform 42ms, setup 0ms, collect 26ms, tests 2ms, environment 0ms, prepare 101ms)

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.