Automated Testing and Quality Assurance

title: "Automated Testing and Quality Assurance" description: "Research on AI-driven test generation, execution, and quality metrics" date: 2026-02-06 topics: [testing, quality, automation, test-generation] sources: 0 status: initial

Automated Testing and Quality Assurance

Overview

AI can augment testing at multiple levels: generating tests, selecting which tests to run, analyzing failures, and predicting risky code changes. This research covers test automation patterns with AI integration.

Test Generation Strategies

1. Property-Based Test Generation

typescript
interface PropertyBasedTesting {
  async generateTests(functionUnderTest: Function): Promise<TestCase[]> {
    // Analyze function signature and types
    const properties = await this.inferProperties(functionUnderTest);
    
    // Generate test cases covering edge cases
    const cases = await this.generateEdgeCases(properties);
    
    // Use fuzzing for unexpected inputs
    const fuzzCases = this.generateFuzzInputs(properties);
    
    return [...cases, ...fuzzCases];
  }
}

// Example properties
interface Property {
  name: string;
  invariants: Invariant[];
  preconditions: Predicate[];
  postconditions: Predicate[];
}

2. Behavior-Driven Test Generation

typescript
interface BehaviorDrivenTesting {
  async generateFromSpec(spec: UserStory): Promise<TestSuite> {
    // Parse acceptance criteria
    const criteria = await this.parseAcceptanceCriteria(spec);
    
    // Generate test scenarios
    const scenarios = criteria.map(c => ({
      given: c.preconditions,
      when: c.action,
      then: c.expectedOutcome,
      tests: this.generateTestCases(c)
    }));
    
    return this.compileTestSuite(scenarios);
  }
}

3. Regression Test Generation from Failures

typescript
interface FailureDrivenTesting {
  async generateFromFailure(
    failure: ProductionError
  ): Promise<TestCase> {
    // Reconstruct failure scenario
    const context = await this.analyzeStackTrace(failure);
    
    // Create minimal reproduction
    const reproduction = await this.minimizeReproduction(context);
    
    // Generate test case
    return {
      name: `regression: ${failure.id}`,
      setup: reproduction.setup,
      execute: reproduction.trigger,
      assertions: reproduction.expectedBehavior
    };
  }
}

Test Selection and Prioritization

Risk-Based Test Selection

typescript
interface TestSelector {
  async selectTests(
    changes: CodeChange[],
    allTests: TestCase[]
  ): Promise<TestCase[]> {
    const riskScores = await Promise.all(
      allTests.map(async test => ({
        test,
        score: await this.calculateRisk(test, changes)
      }))
    );
    
    // Sort by risk and select top N
    return riskScores
      .sort((a, b) => b.score - a.score)
      .slice(0, this.maxTests)
      .map(r => r.test);
  }
  
  calculateRisk(test: TestCase, changes: CodeChange[]): number {
    return {
      codeCoverage: this.coverageOverlap(test, changes),
      historicalFailure: this.failureRate(test),
      complexity: this.cyclomaticComplexity(test),
      dependencies: this.dependencyCount(test)
    };
  }
}

ML-Based Test Impact Analysis

typescript
interface ImpactAnalyzer {
  async predictImpact(
    change: CodeChange
  ): Promise<TestImpact[]> {
    // Use historical data to predict which tests
    // are most likely to be affected by this change
    const features = this.extractFeatures(change);
    
    const predictions = await this.model.predict(features);
    
    return predictions
      .filter(p => p.probability > THRESHOLD)
      .sort((a, b) => b.probability - a.probability);
  }
}

Test Execution Patterns

Adaptive Test Execution

typescript
interface AdaptiveTestRunner {
  async runAdaptively(tests: TestCase[]): Promise<Results> {
    const batches = this.createBatches(tests);
    const results: Results = [];
    
    for (const batch of batches) {
      const batchResults = await this.runBatch(batch);
      results.push(...batchResults);
      
      // Early termination if critical tests fail
      if (this.hasCriticalFailures(batchResults)) {
        await this.reportEarlyFailure(results);
        break;
      }
      
      // Adjust strategy based on results
      this.updateStrategy(batchResults);
    }
    
    return results;
  }
}

Parallel Test Distribution

typescript
interface TestDistributor {
  async distribute(tests: TestCase[], workers: number): Promise<Results> {
    // Estimate test durations from historical data
    const estimates = await Promise.all(
      tests.map(t => this.estimateDuration(t))
    );
    
    // Balance load across workers
    const distribution = this.balanceLoad(estimates, workers);
    
    // Execute in parallel
    const workerResults = await Promise.all(
      distribution.map(d => this.runTests(d.tests))
    );
    
    return this.mergeResults(workerResults);
  }
}

Failure Analysis and Debugging

Automated Root Cause Analysis

typescript
interface RootCauseAnalyzer {
  async analyzeFailure(failure: TestFailure): Promise<Diagnosis> {
    // Collect context
    const context = await this.gatherContext(failure);
    
    // Compare with recent changes
    const recentChanges = await this.getRecentChanges();
    
    // Identify likely causes
    const causes = await this.rankCauses(context, recentChanges);
    
    return {
      primaryCause: causes[0],
      confidence: causes[0].confidence,
      alternatives: causes.slice(1, 3),
      suggestedFix: await this.suggestFix(causes[0])
    };
  }
}

Flaky Test Detection and Handling

typescript
interface FlakyTestDetector {
  async analyzeFlakiness(test: TestCase): Promise<FlakinessReport> {
    // Run test multiple times
    const runs = await Promise.all(
      Array(10).fill(0).map(() => this.runTest(test))
    );
    
    const passRate = runs.filter(r => r.passed).length / runs.length;
    
    if (passRate < 1.0) {
      return {
        test,
        passRate,
        failureModes: this.categorizeFailures(runs),
        possibleCauses: this.identifyFlakinessCauses(runs),
        recommendations: this.suggestStabilization(test)
      };
    }
  }
}

Quality Metrics

Code Quality Indicators

typescript
interface QualityMetrics {
  // Coverage metrics
  lineCoverage: number;
  branchCoverage: number;
  functionCoverage: number;
  
  // Change metrics
  coverageDelta: number;
  untestedChanges: CodeChange[];
  
  // Test quality
  testToCodeRatio: number;
  assertionDensity: number;
  mutationScore: number;
  
  // Maintenance metrics
  testMaintainability: number;
  testDuplication: number;
  testChurnRate: number;
}

Test Health Dashboard

typescript
interface TestHealthMonitor {
  async generateReport(): Promise<HealthReport> {
    return {
      // Overall health
      passRate: this.calculatePassRate(),
      duration: this.calculateDuration(),
      flakiness: this.calculateFlakiness(),
      
      // Trends
      weekOverWeek: this.calculateTrend(7),
      coverageTrend: this.calculateCoverageTrend(),
      
      // Action items
      criticalIssues: await this.identifyCriticalIssues(),
      recommendations: await this.generateRecommendations()
    };
  }
}

CI/CD Integration

Test Gates

yaml
# .github/workflows/test.yml
test_gates:
  unit_tests:
    command: bun test
    coverage_threshold: 80
    max_duration: 5m
    
  integration_tests:
    command: bun test:integration
    coverage_threshold: 60
    max_duration: 10m
    depends_on: [unit_tests]
    
  e2e_tests:
    command: bun test:e2e
    coverage_threshold: 40
    max_duration: 20m
    depends_on: [integration_tests]
    selector: risk_based  # Only run affected tests

Smart Retries

typescript
interface SmartRetry {
  async runWithRetry(test: TestCase): Promise<Result> {
    let attempts = 0;
    const maxAttempts = test.critical ? 3 : 1;
    
    while (attempts < maxAttempts) {
      const result = await this.runTest(test);
      
      if (result.passed) {
        return result;
      }
      
      attempts++;
      
      // Check if failure is retryable
      if (!this.isRetryable(result.error)) {
        return result;
      }
      
      // Exponential backoff
      await this.delay(Math.pow(2, attempts) * 1000);
    }
    
    return result;
  }
}

Observability

Test Execution Traces

typescript
interface TestTrace {
  testId: string;
  startTime: Date;
  endTime: Date;
  duration: number;
  steps: StepTrace[];
  resources: ResourceUsage;
  dependencies: DependencyCall[];
}

interface StepTrace {
  name: string;
  startTime: Date;
  endTime: Date;
  assertions: AssertionResult[];
}

Test Cost Analysis

typescript
interface CostAnalyzer {
  async analyzeTestCost(test: TestCase): Promise<CostBreakdown> {
    return {
      compute: await this.calculateComputeCost(test),
      storage: this.calculateStorageCost(test),
      externalCalls: await this.calculateAPICosts(test),
      total: this.sumCosts(...)
    };
  }
  
  async optimizeCosts(tests: TestCase[]): Promise<Optimization[]> {
    // Identify expensive tests
    // Suggest faster alternatives
    // Recommend parallelization
  }
}

Research Gaps

Optimal test generation strategies per code type
Balancing test coverage vs. execution time
Handling non-deterministic systems
Visual/UI test automation reliability
Cross-browser testing optimization