1 files changed, 87 insertions, 0 deletions
diff --git a/src/io/fs/glob_test.go b/src/io/fs/glob_test.go
new file mode 100644
index 0000000..f19bebe
--- /dev/null
+++ b/src/io/fs/glob_test.go
@@ -0,0 +1,87 @@
+// Copyright 2020 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fs_test
+
+import (
+	. "io/fs"
+	"os"
+	"path"
+	"testing"
+)
+
+var globTests = []struct {
+	fs              FS
+	pattern, result string
+}{
+	{os.DirFS("."), "glob.go", "glob.go"},
+	{os.DirFS("."), "gl?b.go", "glob.go"},
+	{os.DirFS("."), `gl\ob.go`, "glob.go"},
+	{os.DirFS("."), "*", "glob.go"},
+	{os.DirFS(".."), "*/glob.go", "fs/glob.go"},
+}
+
+func TestGlob(t *testing.T) {
+	for _, tt := range globTests {
+		matches, err := Glob(tt.fs, tt.pattern)
+		if err != nil {
+			t.Errorf("Glob error for %q: %s", tt.pattern, err)
+			continue
+		}
+		if !contains(matches, tt.result) {
+			t.Errorf("Glob(%#q) = %#v want %v", tt.pattern, matches, tt.result)
+		}
+	}
+	for _, pattern := range []string{"no_match", "../*/no_match", `\*`} {
+		matches, err := Glob(os.DirFS("."), pattern)
+		if err != nil {
+			t.Errorf("Glob error for %q: %s", pattern, err)
+			continue
+		}
+		if len(matches) != 0 {
+			t.Errorf("Glob(%#q) = %#v want []", pattern, matches)
+		}
+	}
+}
+
+func TestGlobError(t *testing.T) {
+	bad := []string{`[]`, `nonexist/[]`}
+	for _, pattern := range bad {
+		_, err := Glob(os.DirFS("."), pattern)
+		if err != path.ErrBadPattern {
+			t.Errorf("Glob(fs, %#q) returned err=%v, want path.ErrBadPattern", pattern, err)
+		}
+	}
+}
+
+// contains reports whether vector contains the string s.
+func contains(vector []string, s string) bool {
+	for _, elem := range vector {
+		if elem == s {
+			return true
+		}
+	}
+	return false
+}
+
+type globOnly struct{ GlobFS }
+
+func (globOnly) Open(name string) (File, error) { return nil, ErrNotExist }
+
+func TestGlobMethod(t *testing.T) {
+	check := func(desc string, names []string, err error) {
+		t.Helper()
+		if err != nil || len(names) != 1 || names[0] != "hello.txt" {
+			t.Errorf("Glob(%s) = %v, %v, want %v, nil", desc, names, err, []string{"hello.txt"})
+		}
+	}
+
+	// Test that ReadDir uses the method when present.
+	names, err := Glob(globOnly{testFsys}, "*.txt")
+	check("readDirOnly", names, err)
+
+	// Test that ReadDir uses Open when the method is not present.
+	names, err = Glob(openOnly{testFsys}, "*.txt")
+	check("openOnly", names, err)
+}