From a2d12201adb3143c8f1f3d1528c1c0ab961ab98d Mon Sep 17 00:00:00 2001
From: "Billie H. Cleek" <bhcleek@gmail.com>
Date: Sat, 20 Dec 2014 17:05:05 -0800
Subject: [PATCH] cmd/go: detect which VCS to use with Bitbucket when the API
 call fails.

      The API call will fail when Bitbucket repositories are private. In
that case, probe for the repository using vcsCmd.ping.

      Fixes #5375

Change-Id: Ia604ecf9014805579dfda4b5c8e627a52783d56e
Reviewed-on: https://go-review.googlesource.com/1910
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
---
 src/cmd/go/bootstrap.go |  8 ++++++++
 src/cmd/go/http.go      | 14 +++++++++++++-
 src/cmd/go/vcs.go       | 23 +++++++++++++++++++----
 3 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/src/cmd/go/bootstrap.go b/src/cmd/go/bootstrap.go
index dc7ed5f4c0..0c13380054 100644
--- a/src/cmd/go/bootstrap.go
+++ b/src/cmd/go/bootstrap.go
@@ -17,6 +17,14 @@ import (
 
 var errHTTP = errors.New("no http in bootstrap go command")
 
+type httpError struct {
+	statusCode int
+}
+
+func (e *httpError) Error() string {
+	panic("unreachable")
+}
+
 func httpGET(url string) ([]byte, error) {
 	return nil, errHTTP
 }
diff --git a/src/cmd/go/http.go b/src/cmd/go/http.go
index 107b820f28..8b1247bfbe 100644
--- a/src/cmd/go/http.go
+++ b/src/cmd/go/http.go
@@ -24,6 +24,16 @@ import (
 // changed by tests, without modifying http.DefaultClient.
 var httpClient = http.DefaultClient
 
+type httpError struct {
+	status     string
+	statusCode int
+	url        string
+}
+
+func (e *httpError) Error() string {
+	return fmt.Sprintf("%s: %s", e.url, e.status)
+}
+
 // httpGET returns the data from an HTTP GET request for the given URL.
 func httpGET(url string) ([]byte, error) {
 	resp, err := httpClient.Get(url)
@@ -32,7 +42,9 @@ func httpGET(url string) ([]byte, error) {
 	}
 	defer resp.Body.Close()
 	if resp.StatusCode != 200 {
-		return nil, fmt.Errorf("%s: %s", url, resp.Status)
+		err := &httpError{status: resp.Status, statusCode: resp.StatusCode, url: url}
+
+		return nil, err
 	}
 	b, err := ioutil.ReadAll(resp.Body)
 	if err != nil {
diff --git a/src/cmd/go/vcs.go b/src/cmd/go/vcs.go
index 86f5ea82e8..43027134e1 100644
--- a/src/cmd/go/vcs.go
+++ b/src/cmd/go/vcs.go
@@ -808,10 +808,25 @@ func bitbucketVCS(match map[string]string) error {
 	url := expand(match, "https://api.bitbucket.org/1.0/repositories/{bitname}")
 	data, err := httpGET(url)
 	if err != nil {
-		return err
-	}
-	if err := json.Unmarshal(data, &resp); err != nil {
-		return fmt.Errorf("decoding %s: %v", url, err)
+		if httpErr, ok := err.(*httpError); ok && httpErr.statusCode == 403 {
+			// this may be a private repository. If so, attempt to determine which
+			// VCS it uses. See issue 5375.
+			root := match["root"]
+			for _, vcs := range []string{"git", "hg"} {
+				if vcsByCmd(vcs).ping("https", root) == nil {
+					resp.SCM = vcs
+					break
+				}
+			}
+		}
+
+		if resp.SCM == "" {
+			return err
+		}
+	} else {
+		if err := json.Unmarshal(data, &resp); err != nil {
+			return fmt.Errorf("decoding %s: %v", url, err)
+		}
 	}
 
 	if vcsByCmd(resp.SCM) != nil {
-- 
2.48.1