Changes based on code review:
1. Remove redundant strings.Contains check in isExactTestPackage
The equality check on the next line handles both cases, making
the early return unnecessary.
2. Extract package selection logic into selectBestPackages function
This reduces code duplication and allows the test to call the
actual implementation rather than copying the logic.
3. Add TestSelectBestPackages to test the new function
Comprehensive test covering single packages, test vs production,
exact vs nested tests, and multiple packages.
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
When CODEQL_EXTRACTOR_GO_OPTION_EXTRACT_TESTS=true is set, the Go
extractor was incorrectly skipping internal test files (package foo)
at repository roots when the project contains nested test packages.
Root Cause:
The extractor selected package variants by longest ID string, but this
heuristic fails when nested packages have tests. For a package like
"github.com/go-git/go-git/v6", packages.Load returns multiple variants:
1. "github.com/go-git/go-git/v6" (19 files, production only)
2. "github.com/go-git/go-git/v6 [github.com/go-git/go-git/v6.test]"
(39 files, production + 20 root tests) ← Should select this
3. "github.com/go-git/go-git/v6 [github.com/go-git/go-git/v6/plumbing/format/packfile.test]"
(19 files, test dependency) ← Was incorrectly selected (longest string)
The old logic selected variant #3 (76 chars) over #2 (68 chars),
causing 20 root test files to be missing from the database.
Fix:
Replace string length comparison with a better heuristic that prefers:
1. Exact test packages (e.g., "pkg [pkg.test]") over nested dependencies
2. Packages with more Syntax nodes (more files to extract)
3. String length as a tiebreaker
This ensures the extractor selects the variant with the most complete
test coverage, particularly for root-level internal tests.
Testing:
- Added comprehensive unit tests covering the selection logic
- Tests simulate the real-world go-git scenario
- All tests pass
Impact:
Root-level external tests (package foo_test) were already extracted
correctly. This fix ensures internal tests (package foo) at the root
are now also extracted when they exist alongside nested test packages.
Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>
