oauth2/google: add config type to use Cloud SDK credentials

Change-Id: Ied7fecc0cb155c33faca7766b81221eacb3aa0c0
Reviewed-on: https://go-review.googlesource.com/1670
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Burcu Dogan <jbd@google.com>

internal/oauth2_test.go

@@ -0,0 +1,62 @@
+// Copyright 2014 The oauth2 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 internal contains support packages for oauth2 package.
+package internal
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestParseINI(t *testing.T) {
+	tests := []struct {
+		ini  string
+		want map[string]map[string]string
+	}{
+		{
+			`root = toor
+[foo]  
+bar = hop
+ini = nin
+`,
+			map[string]map[string]string{
+				"":    map[string]string{"root": "toor"},
+				"foo": map[string]string{"bar": "hop", "ini": "nin"},
+			},
+		},
+		{
+			`[empty]
+[section]
+empty=
+`,
+			map[string]map[string]string{
+				"":        map[string]string{},
+				"empty":   map[string]string{},
+				"section": map[string]string{"empty": ""},
+			},
+		},
+		{
+			`ignore
+[invalid
+=stuff
+;comment=true
+`,
+			map[string]map[string]string{
+				"a": map[string]string{},
+			},
+		},
+	}
+	for _, tt := range tests {
+		result, err := ParseINI(strings.NewReader(tt.ini))
+		if err != nil {
+			t.Errorf("ParseINI(%q) error %v, want: no error", tt.ini, err)
+			continue
+		}
+		if !reflect.DeepEqual(result, tt.want) {
+			t.Errorf("ParseINI(%q) = %#v, want: %#v", tt.ini, result, tt.want)
+		}
+	}
+}