result/processors: treat all non-Go source as special autogenerated files

Prior to this change golangci-lint would attempt to follow //line
directives into generation description files unless they were in a small
set of fake files used by goyacc. Now we consider all non-Go source as
special.

Author: kortschak

pkg/result/processors/autogenerated_exclude.go

@@ -43,8 +43,8 @@ func (p *AutogeneratedExclude) Process(issues []result.Issue) ([]result.Issue, e
 
 func isSpecialAutogeneratedFile(filePath string) bool {
 	fileName := filepath.Base(filePath)
-	// fake files to which //line points to for goyacc generated files
-	return fileName == "yacctab" || fileName == "yaccpar" || fileName == "NONE"
+	// fake files or generation definitions to which //line points to for generated files
+	return filepath.Ext(fileName) != ".go"
 }
 
 func (p *AutogeneratedExclude) shouldPassIssue(i *result.Issue) (bool, error) {