Fix panic on directories with only _test.go files#256
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When a directory contains only *_test.go files belonging to an external '*_test' package, packages.Load (with Tests: true) returns a synthetic regular package whose Syntax slice is empty. indexVisitPackages then panicked on pkg.Syntax[0] while attaching package SymbolInformation. Skip the package-symbol attachment when len(pkg.Syntax) == 0; the external *_test package has its own non-empty entry and is processed normally. Fixes #255
A directory containing only *_test.go files (belonging to an external *_test package) used to panic with 'index out of range [0] with length 0' in indexVisitPackages. This snapshot exercises that scenario and pins the resulting index for the package and its external test package.
The bug only requires a directory whose Go files all belong to an external '*_test' package, leaving the synthetic regular package with empty Syntax. A single pr256_test.go at the module root is enough; the extra main.go and nested tests/comment/ subdirectory aren't needed.
eseliger
approved these changes
May 15, 2026
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When a directory contains only
*_test.gofiles belonging to an external '*_test' package,packages.Loadreturns a synthetic regular package whose Syntax slice is empty.indexVisitPackagesthen panicked onpkg.Syntax[0].Fixes #255