newt: Fix shallow upgrade with specific commit version

newt/downloader/downloader.go

@@ -61,6 +61,9 @@ type Downloader interface {
 	// Fetches all remotes.
 	Fetch(path string) error
 
+	// Fetches specific commit
+	FetchCommit(path string, commit string) error
+
 	// Checks out the specified commit (hash, tag, or branch).  Always puts the
 	// repo in a "detached head" state.
 	Checkout(path string, commit string) error
@@ -774,6 +777,11 @@ func (gd *GithubDownloader) Fetch(repoDir string) error {
 	})
 }
 
+func (gd *GithubDownloader) FetchCommit(repoDir string, commit string) error {
+	_, err := executeGitCommand(repoDir, []string{"fetch", "--depth=1", "origin", commit}, true)
+	return err
+}
+
 func (gd *GithubDownloader) password() string {
 	if gd.Password != "" {
 		return gd.Password
@@ -943,6 +951,11 @@ func (gd *GitDownloader) Fetch(repoDir string) error {
 	})
 }
 
+func (gd *GitDownloader) FetchCommit(repoDir string, commit string) error {
+	_, err := executeGitCommand(repoDir, []string{"fetch", "--depth=1", "origin", commit}, true)
+	return err
+}
+
 func (gd *GitDownloader) FetchFile(
 	commit string, path string, filename string, dstDir string) error {
 
@@ -1043,6 +1056,11 @@ func (ld *LocalDownloader) Fetch(path string) error {
 	return ld.Clone(ld.MainBranch(), path)
 }
 
+func (ld *LocalDownloader) FetchCommit(path string, commit string) error {
+	_, err := executeGitCommand(path, []string{"fetch", "--depth=1", "origin", commit}, true)
+	return err
+}
+
 func (ld *LocalDownloader) Checkout(path string, commit string) error {
 	_, err := executeGitCommand(path, []string{"checkout", commit}, true)
 	return err

newt/repo/version.go

@@ -126,6 +126,15 @@ func (r *Repo) VersionIsValid(ver newtutil.RepoVersion) bool {
 	}
 
 	cs, _ := r.downloader.CommitsFor(r.Path(), ver.Commit)
+
+	// Try to fetch commit if it was not found
+	if len(cs) <= 0 {
+		err := r.Downloader().FetchCommit(r.Path(), ver.Commit)
+		if err != nil {
+			return false
+		}
+		cs, _ = r.downloader.CommitsFor(r.Path(), ver.Commit)
+	}
 	return len(cs) > 0
 }