Managing Flaky Tests

Cased identifies flaky tests, analyzes failure patterns, and generates pull requests to fix or remove problematic tests—maintaining reliable CI/CD pipelines.

Flaky tests kill productivity. They erode test suite confidence, slow deployments, and waste developer time. Cased detects flaky tests intelligently and remediates them automatically.

How Flaky Test Management Works

Cased combines data analysis with automated remediation:

Test Execution Monitoring: Monitors CI/CD pipeline test results across runs
Pattern Analysis: Analyzes failure patterns to identify flaky behavior
Flakiness Scoring: Scores tests by failure frequency, inconsistency, and impact
Automated Remediation: Creates pull requests to fix or remove flaky tests
Continuous Monitoring: Catches new flaky tests through ongoing analysis

Flaky Test Detection

Statistical Analysis

Failure Rate Tracking: Tracks test pass/fail rates over time
Consistency Scoring: Identifies inconsistent failures across identical conditions
Environmental Correlation: Detects environment-specific failures
Timing Analysis: Finds timing issues and race conditions

Pattern Recognition

Error Message Analysis: Groups similar failures and identifies root causes
Dependency Mapping: Maps test dependencies and cascading failures
Historical Trends: Tracks test reliability changes over time
Impact Assessment: Measures flaky test impact on pipeline reliability

Supported Test Frameworks

JavaScript/TypeScript

Jest: Full support for Jest test results and reporting
Vitest: Native integration with Vitest test runner
Mocha: Analysis of Mocha test outputs and failure patterns
Cypress: End-to-end test flakiness detection

Python

pytest: Comprehensive pytest result analysis
unittest: Standard Python unittest framework support
nose: Legacy nose framework compatibility

Other Languages

JUnit: Java test framework analysis
RSpec: Ruby test framework support
Go Test: Native Go testing framework
PHPUnit: PHP test framework integration

Automated Remediation

Pull Request Generation

Cased creates pull requests automatically to address flaky tests:

# Example PR Description Generated by Cased

## Flaky Test Remediation

This PR addresses flaky tests identified in the test suite:

### Tests Modified:
- `test_user_authentication_flow` - Added retry logic for network calls
- `test_database_connection` - Improved connection cleanup
- `test_async_operation` - Fixed race condition with proper awaits

### Tests Removed:
- `test_deprecated_feature` - Consistently failing, feature removed
- `test_flaky_integration` - Unreliable external dependency

### Analysis:
- 3 tests showed >30% failure rate over last 30 days
- 2 tests had inconsistent failures across environments
- Total pipeline reliability improved from 85% to 96%

Remediation Strategies

Test Stabilization

Retry Logic: Adds intelligent retries for network-dependent tests
Wait Conditions: Implements proper waits for async operations
Mock Improvements: Replaces unreliable external dependencies
Resource Cleanup: Ensures proper test resource cleanup

Test Removal

Deprecated Features: Removes tests for non-existent features
Redundant Coverage: Eliminates duplicate test coverage
Unmaintainable Tests: Removes overly complex or unreliable tests

Integration Examples

GitHub Actions Integration

name: Flaky Test Analysis
on:
  schedule:
    - cron: '0 2 * * *'  # Daily at 2 AM
  workflow_dispatch:

jobs:
  analyze-flaky-tests:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Run Test Suite
        run: npm test -- --reporter=json > test-results.json
        continue-on-error: true

      - name: Analyze with Cased
        run: |
          curl -X POST https://app.cased.com/api/v1/test-analysis/ \
            -H "Authorization: Bearer ${{ secrets.CASED_API_KEY }}" \
            -H "Content-Type: application/json" \
            -d '{
              "repository": "${{ github.repository }}",
              "test_results": "'$(cat test-results.json | base64 -w 0)'",
              "commit_sha": "${{ github.sha }}"
            }'

CI/CD Pipeline Integration

name: Test and Flaky Analysis
on: [push, pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Run Tests
        run: |
          npm test -- --reporter=json --outputFile=test-results.json
          echo "TEST_EXIT_CODE=$?" >> $GITHUB_ENV
        continue-on-error: true

      - name: Report to Cased
        if: always()
        uses: cased/test-analysis-action@v1
        with:
          api_key: ${{ secrets.CASED_API_KEY }}
          test_results_file: test-results.json
          create_pr_on_flaky: true

Flaky Test Dashboard

Mission Control Integration

Flaky Test Overview: Dashboard showing all identified flaky tests
Trend Analysis: Historical view of test reliability improvements
Impact Metrics: Measure how flaky tests affect deployment frequency
Remediation Tracking: Track the status of automated fixes

Key Metrics

Overall Test Reliability: Percentage of test runs that pass completely
Flaky Test Count: Number of tests identified as flaky
Time to Fix: Average time from detection to remediation
Pipeline Impact: How flaky tests affect deployment speed

Best Practices

Test Writing

Isolation: Ensure tests don’t depend on each other
Deterministic: Avoid random data or timing dependencies
Cleanup: Properly clean up resources after each test
Mocking: Mock external dependencies and network calls

Flaky Test Management

Regular Analysis: Run flaky test analysis regularly, not just when problems occur
Immediate Action: Address flaky tests as soon as they’re identified
Root Cause Analysis: Understand why tests are flaky, don’t just add retries
Team Communication: Share flaky test reports with the development team

CI/CD Integration

Fail Fast: Don’t let flaky tests slow down your pipeline
Parallel Analysis: Run flaky test analysis in parallel with regular CI
Automated Remediation: Enable automatic PR creation for obvious fixes
Monitoring: Continuously monitor test reliability metrics

Team Collaboration

Slack Notifications: Get notified when flaky tests are detected or fixed
Assignment: Automatically assign flaky test fixes to relevant team members
Progress Tracking: Track team progress on flaky test remediation
Cross-Environment Comparison: Compare test reliability across different environments

Managing flaky tests with Cased transforms a major development pain point into an automated, manageable process that improves overall development velocity and deployment confidence.