t.Error(err)
			continue
		}
		if sawImport[pkg] == nil {
			sawImport[pkg] = map[string]bool{}
		}
		var bad []string
		for _, imp := range imports {
			sawImport[pkg][imp] = true
			if !policy.HasEdge(pkg, imp) {
				bad = append(bad, imp)
			}
		}
		if bad != nil {
			t.Errorf("unexpected dependency: %s imports %v", pkg, bad)
		}
	}
}

var buildIgnore = []byte("\n//go:build ignore")