Strict mode: treat unknown extensions as errors when checking headers

main.go

@@ -27,6 +27,7 @@ import (
 	"path/filepath"
 	"regexp"
 	"strings"
+	"sync"
 	"text/template"
 	"time"
 
@@ -60,6 +61,7 @@ var (
 	year      = flag.String("y", fmt.Sprint(time.Now().Year()), "copyright year(s)")
 	verbose   = flag.Bool("v", false, "verbose mode: print the name of the files that are modified or were skipped")
 	checkonly = flag.Bool("check", false, "check only mode: verify presence of license headers and exit with non-zero code if missing")
+	strict    = flag.Bool("strict", false, "check license headers in strict mode (files with unknown extensions treated as errors)")
 )
 
 func init() {
@@ -114,6 +116,10 @@ func main() {
 		os.Exit(1)
 	}
 
+	if *strict && !(*checkonly) {
+		log.Fatal("-strict flag must only be used together with -check flag")
+	}
+
 	// convert -skip flags to -ignore equivalents
 	for _, s := range skipExtensionFlags {
 		ignorePatterns = append(ignorePatterns, fmt.Sprintf("**/*.%s", s))
@@ -148,6 +154,8 @@ func main() {
 	// process at most 1000 files in parallel
 	ch := make(chan *file, 1000)
 	done := make(chan struct{})
+	mu := sync.Mutex{} // Protect access to the nonTerminalErrors slice
+	nonTerminalErrors := []error{}
 	go func() {
 		var wg errgroup.Group
 		for f := range ch {
@@ -161,6 +169,13 @@ func main() {
 						return err
 					}
 					if lic == nil { // Unknown fileExtension
+						if *strict {
+							mu.Lock()
+							nonTerminalErrors = append(nonTerminalErrors, fmt.Errorf("unknown extension: %s", f.path))
+							mu.Unlock()
+						} else {
+							log.Printf("unknown extension: %s", f.path)
+						}
 						return nil
 					}
 					// Check if file has a license
@@ -187,10 +202,21 @@ func main() {
 			})
 		}
 		err := wg.Wait()
-		close(done)
+
+		foundNonTerminalErrors := len(nonTerminalErrors) > 0
+		if foundNonTerminalErrors {
+			for _, e := range nonTerminalErrors {
+				log.Printf("%v", e)
+			}
+		}
 		if err != nil {
+			log.Printf("%v", err)
+		}
+		if foundNonTerminalErrors || err != nil {
 			os.Exit(1)
 		}
+
+		close(done)
 	}()
 
 	for _, d := range flag.Args() {