Coding & Development / Code Reviews
Analyze what code paths are missing tests and suggest specific unit or integration tests to add.
Why This Prompt Exists
Most code has tests — but not for the important edge cases.
You get:
- tests that cover happy paths only (not edge cases)
- error handling code with no tests
- boundary conditions (empty lists, zero values) untested
- no tests for the code that’s most likely to break
- high coverage percentage but low confidence
But test coverage is not about percentage.
It is about risk coverage.
- Normal case: typical inputs, expected outputs
- Edge cases: empty, zero, null, boundary values
- Error cases: invalid inputs, exceptions, timeouts
- Boundary conditions: array bounds, off-by-one
- Concurrency: race conditions, deadlocks
Without coverage assessment, you have false confidence.
This framework forces AI to identify missing tests.
The Prompt
Assume the role of a testing strategist who identifies missing test coverage. Your task is to recommend tests for uncovered code paths. Generate: 1. CODE PATHS MISSING TESTS - Specific functions/conditions without tests 2. FOR EACH MISSING PATH: - Input that would trigger it - Expected output/behavior 3. TEST RECOMMENDATION - Unit test for isolated logic - Integration test for component interaction 4. TEST CODE EXAMPLE - Ready-to-use test code 5. PRIORITY (HIGH/MEDIUM/LOW) INPUTS: Function/Code (paste): [PASTE CODE] Existing Tests (if any): [PASTE OR DESCRIBE] Criticality of This Code: [HIGH / MEDIUM / LOW] Known Bug History (if any): [LIST OR "NONE"] RULES: - Check for untested error handling (try/catch blocks) - Check for untested edge cases (empty lists, null, zero) - Check for untested boundary conditions (array bounds, off-by-one) - Check for untested default branches (else/switch default) - Check for untested rare conditions (timeout, network error) - Priority: error handling > edge cases > normal cases - Suggest parameterized tests for multiple similar cases
How To Use It
- Test error handling first — it’s where bugs hide.
- Edge cases (empty lists, null, zero) are more important than more happy path tests.
- Use parameterized tests to cover multiple cases with one test function.
- Priority: error handling > edge cases > boundary conditions > normal cases.
- Don’t aim for 100% coverage — aim for high-risk coverage.
Example Input
Function/Code:
def divide(a, b):
if b == 0:
raise ValueError(“Cannot divide by zero”)
return a / b
Existing Tests: Test for normal division (4 / 2 = 2)
Criticality of This Code: HIGH (used in payment calculations)
Known Bug History: None yet
Why It Works
Most tests miss critical edge cases.
This framework improves outcomes by forcing:
- missing path identification (detection)
- input specification (reproducibility)
- test recommendation (action)
- code example (execution)
- priority ranking (focus)
Great coverage assessment doesn’t track percentage — it tracks risk.
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