Merge pull request #7 from sinshutu/master

Add command fetch

README.md

@@ -97,6 +97,18 @@ $ gst update
 Already up-to-date.
 ```
 
+### fetch
+
+`git fetch --tags --prune` to all repositories.
+
+```
+$ gst fetch
+/Users/uetchy/Repos/src/github.com/uetchy/gst
+ * [new branch]      dev        -> origin/dev
+ - [deleted]         (none)     -> origin/test
+ * [new tag]         v1.0.0     -> v1.0.0
+```
+
 ## Quick Install
 
 See [releases](https://github.com/uetchy/gst/releases/latest).
@@ -135,4 +147,4 @@ chmod +x /usr/local/bin/gst
 
 ```
 go get github.com/uetchy/gst
-```
+```

command_fetch.go

@@ -0,0 +1,39 @@
+package main
+
+import (
+	"fmt"
+	"github.com/codegangsta/cli"
+	"github.com/daviddengcn/go-colortext"
+)
+
+var flagsOfFetch = []cli.Flag{
+	cli.BoolFlag{
+		Name:  "short, s",
+		Usage: "shorten result for pipeline processing",
+	},
+}
+
+var commandFetch = cli.Command{
+	Name:   "fetch",
+	Action: doFetch,
+	Flags:  flagsOfFetch,
+}
+
+func doFetch(c *cli.Context) error {
+	ghqPath := verifyGhqPath()
+	repos := searchForRepos(ghqPath)
+
+	// Listing repos
+	for repo := range repos {
+		printlnWithColor(repo.Path, ct.Cyan)
+		out, err := GitFetch(repo.Path)
+		if err != nil {
+			fmt.Println(err)
+			continue
+		}
+		if out != "" {
+			fmt.Println(err)
+		}
+	}
+	return nil
+}

git.go

@@ -157,3 +157,26 @@ func GitPull(targetPath string) (string, error) {
 
 	return string(out), nil
 }
+
+// GitFetch update tags and remove old branches
+func GitFetch(targetPath string) (string, error) {
+	if err := os.Chdir(targetPath); err != nil {
+		return "", err
+	}
+
+	out, err := exec.Command("git", "fetch", "--tags", "--prune").CombinedOutput()
+	if err != nil {
+		eout := string(out)
+		if strings.HasPrefix(eout, "conq: repository does not exist.") {
+			return "", &RepositoryNotFoundError{targetPath}
+		} else if strings.HasPrefix(eout, "ERROR: Repository not found.") {
+			return "", &RepositoryNotFoundError{targetPath}
+		} else if strings.HasPrefix(eout, "fatal: No remote repository specified.") {
+			return "", &NoRemoteSpecifiedError{targetPath}
+		} else {
+			return "", err
+		}
+	}
+
+	return string(out), nil
+}

main.go

@@ -15,6 +15,7 @@ var Commands = []cli.Command{
 	commandRemove,
 	commandDoctor,
 	commandUpdate,
+	commandFetch,
 }
 
 func main() {