Fix nil-pointer panic when pkg.Fset.File returns nil#260
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When pkg.Fset.File(f.Package) returns nil (e.g. for files whose package position is not registered in the package's FileSet, as can happen when indexing directories with multiple conflicting 'package main' files such as the Go compiler's own test corpus), scip-go would panic with a nil pointer dereference at *token.File.Name(). Guard all five call sites of pkg.Fset.File(...).Name() in VisitPackageSyntax, ListMissing, Index, and indexVisitPackages, skipping syntax files with unknown positions instead of crashing.
…rywhere Replace the per-call-site nil guards added in the previous commit with a single filter in addImportsToPkgs that drops *ast.File entries whose f.Package has no corresponding *token.File in pkg.Fset. These are zero-decl placeholders produced by packages.Load for files it could not parse (e.g. conflicting 'package main' declarations in the Go compiler's test corpus). Restores VisitPackageSyntax, ListMissing, Index and indexVisitPackages to their original shape.
Minimal repro of the bug fixed in the previous commit: a directory containing a .go file with no 'package' declaration alongside a valid sibling file. Before the loader filter, indexing this directory panicked with a nil-pointer dereference at pkg.Fset.File(f.Package).Name(); afterwards the broken file is silently dropped and the valid file is indexed normally.
Pairs with no_package.go and makes the contrast between the indexable and the skipped file obvious from the filenames alone.
eseliger
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May 20, 2026
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nice test to visualize this problem, thanks!
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When
packages.Loadreturns zero-decl*ast.Fileplaceholders for files it cannot parse, theirf.Packageistoken.NoPosandpkg.Fset.File(f.Package)is nil. Every call topkg.Fset.File(f.Package).Name()in the indexer then panics.Drop those entries once in
addImportsToPkgsso callers never see them.