path/filepath: Glob fails if it has a wildcard and ends with /

The Glob tries to get the parent directory of the given directory.
When a trailing slash is present, filepath.Split returns the path as it is as it can not split it further.
This fix cleans the path first by remoivng any trailing slash before getting the parent directory.

Fixes golang#33617

src/path/filepath/match.go

@@ -239,13 +239,9 @@ func Glob(pattern string) (matches []string, err error) {
 		return []string{pattern}, nil
 	}
 
-	dir, file := Split(pattern)
-	volumeLen := 0
-	if runtime.GOOS == "windows" {
-		volumeLen, dir = cleanGlobPathWindows(dir)
-	} else {
-		dir = cleanGlobPath(dir)
-	}
+	_, dir := cleanPath(pattern)
+	dir, file := Split(dir)
+	volumeLen, dir := cleanPath(dir)
 
 	if !hasMeta(dir[volumeLen:]) {
 		return glob(dir, file, nil)
@@ -270,6 +266,15 @@ func Glob(pattern string) (matches []string, err error) {
 	return
 }
 
+// cleanPath cleans the path depending on GOOS
+func cleanPath(dir string) (int, string) {
+	if runtime.GOOS != "windows" {
+		return cleanGlobPathWindows(dir)
+	}
+
+	return 0, cleanGlobPath(dir)
+}
+
 // cleanGlobPath prepares path for glob matching.
 func cleanGlobPath(path string) string {
 	switch path {
@@ -279,7 +284,10 @@ func cleanGlobPath(path string) string {
 		// do nothing to the path
 		return path
 	default:
-		return path[0 : len(path)-1] // chop off trailing separator
+		if os.IsPathSeparator(path[len(path)-1]) {
+			return path[0 : len(path)-1] // chop off trailing separator
+		}
+		return path
 	}
 }
 
@@ -298,7 +306,10 @@ func cleanGlobPathWindows(path string) (prefixLen int, cleaned string) {
 		if vollen >= len(path) {
 			vollen = len(path) - 1
 		}
-		return vollen, path[0 : len(path)-1] // chop off trailing separator
+		if os.IsPathSeparator(path[len(path)-1]) {
+			return vollen, path[0 : len(path)-1] // chop off trailing separator
+		}
+		return vollen, path
 	}
 }
 

src/path/filepath/match_test.go

@@ -123,6 +123,7 @@ var globTests = []struct {
 	{"mat?h.go", "match.go"},
 	{"*", "match.go"},
 	{"../*/match.go", "../filepath/match.go"},
+	{"../../*/filepath/", "../../path/filepath"},
 }
 
 func TestGlob(t *testing.T) {