test: add comprehensive Java run-and-parse integration tests

[misrasaurabh1]

Summary

Adds end-to-end integration tests for Java test instrumentation, execution, and result parsing pipeline, analogous to existing Python and JavaScript tests.

Changes

Test Suite (tests/test_languages/test_java/test_run_and_parse.py)

Behavior Tests (3):

• test_behavior_single_test_method - Full pipeline for single @test method
• test_behavior_multiple_test_methods - Multiple @test methods in one class
• test_behavior_return_value_correctness - Java Comparator return value validation via manually constructed SQLite databases with Kryo-encoded values

Performance Tests (2):

• test_performance_inner_loop_count_and_timing - Validates 2 outer × 2 inner = 4 results with <2% timing variance
• test_performance_multiple_test_methods_inner_loop - Validates 2 methods × 2 outer × 2 inner = 8 results

PreciseWaiter Implementation:

public class PreciseWaiter {
    private volatile long busyWork = 0;
    
    public long waitNanos(long targetNanos) {
        long startTime = System.nanoTime();  // Monotonic clock
        long endTime = startTime + targetNanos;
        
        while (System.nanoTime() < endTime) {
            busyWork++;  // Prevent CPU sleep/optimization
        }
        
        return System.nanoTime() - startTime;
    }
}

Uses System.nanoTime() (monotonic clock) with busy-wait loop to achieve <2% coefficient of variation in measurements.

Infrastructure Improvements

1. Parameter Flow for inner_iterations

Added proper parameter passing through the call chain:

• tests → function_optimizer.run_and_parse_tests(inner_iterations=2)
• → verification.run_benchmarking_tests(inner_iterations=2)
• → language_support.run_benchmarking_tests(inner_iterations=2)
• → Java test_runner.run_benchmarking_tests(inner_iterations=2)

2. Language-Agnostic Parameter Naming

Renamed parameters used by Java/JavaScript (not just pytest):

• pytest_min_loops → min_outer_loops
• pytest_max_loops → max_outer_loops
• pytest_inner_iterations → inner_iterations
• pytest_timeout → timeout
• pytest_target_runtime_seconds → target_runtime_seconds

Updated across:

• codeflash/verification/test_runner.py
• codeflash/optimization/function_optimizer.py
• All test files in tests/ directory

Test Results

✅ 5 new tests passed in 15.36s
✅ All 3257 existing tests still pass

Measurements validate:

• Timing accuracy: Mean within ±2% of 10ms target
• Consistency: CV < 2% across all measurements
• total_passed_runtime(): Correctly sums minimum runtime per test case (including iteration_id grouping)
• Result counts: Correct outer × inner loop multiplication

Test Plan

• Created comprehensive test suite with 5 tests (3 behavior, 2 performance)
• All new tests pass
• All existing tests pass (3257 tests)
• Validated timing accuracy (<2% variance)
• Validated total_passed_runtime() correctness
• Tests documented with clear docstrings

🤖 Generated with Claude Code

[misrasaurabh1]

@HeshamHM28 i created this spin-wait implementation and saw that it was a lot more precise. you can use it in your work

[claude]

PR Review Summary

Prek Checks

✅ All checks pass — ruff check and ruff format clean.

Mypy

⚠️ Pre-existing mypy errors in function_optimizer.py (complex generic types, optional attribute access) and test_runner.py (subprocess overload resolution). These are not introduced by this PR and require broader refactoring to fix — out of scope.

Code Review

Re-review after latest commits (c9cb60a2, eb7c1f00):

No critical issues found. The changes are clean and well-structured:

1. Parameter renames (pytest_* → language-agnostic names): Consistent across all 10 files. pytest_min_loops → min_outer_loops, pytest_max_loops → max_outer_loops, pytest_timeout → timeout, pytest_target_runtime_seconds → target_runtime_seconds.

2. New inner_iterations parameter: Properly threaded through run_and_parse_tests → run_benchmarking_tests → language_support.run_benchmarking_tests. The dynamic kwargs approach in test_runner.py (line 383) works correctly for optional parameter forwarding.

3. New test file (tests/test_languages/test_java/test_run_and_parse.py): 5 well-structured tests (3 behavior, 2 performance) with appropriate tolerances (5% CV, ±5% mean, ±3% total_passed_runtime) accounting for JIT warmup.

4. Previous review comment (ID 2831390272) already resolved — marked as "✅ Fixed in latest commit".

Test Coverage

File	Stmts	Miss	Cover
codeflash/optimization/function_optimizer.py	1320	1048	20.6%
codeflash/verification/test_runner.py	156	55	64.7%

Notes:

• function_optimizer.py has low overall coverage (20.6%) but this is pre-existing — the file has 1320 statements and most optimizer logic paths require end-to-end integration tests. The changes in this PR (parameter renames in run_and_parse_tests and run_concurrency_benchmark) are in code paths exercised by existing tests.
• test_runner.py at 64.7% — the renamed parameters in run_benchmarking_tests are exercised by the test suite.
• New test file adds 5 comprehensive Java integration tests covering the full instrument → run → parse pipeline with both behavior and performance modes.
• Cross-branch comparison not feasible due to parameter renames breaking test compatibility with old source.

Codeflash Optimization PRs

20 open optimization PRs checked — all have consistent CI failures (snyk, java-fibonacci-optimization-no-git, js-*, tracer-replay). None eligible for merge.

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Last updated: 2026-02-20T09:00:00Z