Compare Test Runs

Compare Test Runs

Quick Start

You'll typically receive two test run identifiers. Follow these steps:

1. Run tuist test show <id> --json for both base and head test runs. 2. Run tuist test module list <test-run-id> --json and tuist test suite list <test-run-id> --json to get module and suite breakdowns. 3. Run tuist test case run list <identifier> --json to get individual test case results. 4. Compare failures, flaky tests, durations, and overall status. 5. Inspect failing test cases with tuist test case run show <id> --json. 6. Summarize findings with actionable recommendations.

Step 1: Resolve Test Runs

If base/head are test run IDs or dashboard URLs

Fetch each directly:

tuist test show <base-id> --json
tuist test show <head-id> --json

If base/head are branch names

List recent test runs on each branch to identify test run IDs:

tuist test list --git-branch <base-branch> --json --page-size 5
tuist test list --git-branch <head-branch> --json --page-size 5

Pick the latest test run ID from each branch's results.

Defaults

• If no base is provided, use the project's default branch (usually main).
• If no head is provided, detect the current git branch.

Step 2: Compare Top-Level Metrics

After fetching both test runs, compare:

Step 3: Get Module and Suite Breakdowns

Fetch module and suite-level results for both test runs to understand which areas regressed:

tuist test module list <base-test-run-id> --json
tuist test module list <head-test-run-id> --json

tuist test suite list <base-test-run-id> --json
tuist test suite list <head-test-run-id> --json

Match modules and suites by name across both runs to identify areas with new failures or duration regressions.

Step 4: Get Individual Test Case Results

Fetch test case runs for both test runs:

tuist test case run list <identifier> --json --page-size 100

Match test cases by their name + module_name + suite_name across both runs.

Step 5: Classify Changes

Group test cases into categories:

1. New failures: Tests that passed in base but failed in head. 2. Fixed tests: Tests that failed in base but passed in head. 3. Newly flaky: Tests not flaky in base but flaky in head. 4. No longer flaky: Tests that were flaky in base but stable in head. 5. New tests: Tests present in head but not in base. 6. Removed tests: Tests present in base but not in head. 7. Duration regressions: Tests with >50% duration increase.

Step 6: Inspect Failures

For each new failure, get detailed information:

tuist test case run show <test-case-run-id> --json

Key fields to examine:

• failures[].message -- the assertion or error message
• failures[].path -- source file path
• failures[].line_number -- exact line of failure
• failures[].issue_type -- type of issue
• repetitions -- if present, shows retry behavior (flaky detection)
• crash_report -- crash data if test runner crashed

Step 7: Inspect Attachments

The tuist test case run show output includes attachment and crash report information. Review:

• Screenshots or UI test artifacts
• Log files or crash reports
• Any diagnostic data attached to failing runs

Summary Format

Produce a summary with:

1. Overall verdict: Better, worse, or neutral compared to base. 2. New failures: List each with failure message, file path, and line number. 3. New flaky tests: List with flakiness context. 4. Fixed tests: List tests that are now passing. 5. Duration: Overall and notable per-test regressions. 6. Recommendations: Actionable next steps for each issue.

Example:

Test Run Comparison: base (run-123 on main) vs head (run-456 on feature-x)

Status: success -> failure -- REGRESSION
Duration: 120.5s -> 145.2s (+21%)
Tests: 342 -> 345 (3 new tests)
Failures: 0 -> 2 (2 new failures)
Flaky: 1 -> 3 (2 newly flaky)

New Failures:
1. AuthModuleTests/LoginTests/test_login_with_expired_token
   Message: "Expected status 401, got 500"
   File: Tests/AuthModuleTests/LoginTests.swift:42
   Likely cause: Server error handling changed for expired tokens

2. NetworkTests/RetryTests/test_retry_on_timeout
   Message: "Timed out waiting for retry"
   File: Tests/NetworkTests/RetryTests.swift:87
   Likely cause: Timeout threshold too low after network layer refactor

Newly Flaky:
1. CacheTests/WriteCacheTests/test_concurrent_writes (flaky in 3/5 runs)

Recommendations:
- Fix expired token handling in AuthModule
- Increase timeout in RetryTests or mock the network layer
- Investigate concurrent write synchronization in CacheTests

Done Checklist

• Resolved both base and head test runs
• Compared top-level metrics
• Fetched module and suite breakdowns for both runs
• Identified new failures, fixed tests, and flaky changes
• Inspected failure details for new failures
• Provided actionable recommendations with file paths