_examples: branch example improvements

Signed-off-by: Máximo Cuadros <[email protected]>

Author: mcuadros

_examples/README.md

@@ -6,15 +6,18 @@ Here you can find a list of annotated _go-git_ examples:
 - [showcase](showcase/main.go) - A small showcase of the capabilities of _go-git_
 - [open](open/main.go) - Opening a existing repository cloned by _git_
 - [clone](clone/main.go) - Cloning a repository
-- [clone with context](context/main.go) - Cloning a repository with graceful cancellation.
-- [log](log/main.go) - Emulate `git log` command output iterating all the commit history from HEAD reference
-- [remotes](remotes/main.go) - Working with remotes: adding, removing, etc
-- [progress](progress/main.go) - Printing the progress information from the sideband
+- [commit](commit/main.go) - Commit changes to the current branch to an existent repository
 - [push](push/main.go) - Push repository to default remote (origin)
+- [pull](pull/main.go) - Pull changes from a remote repository
 - [checkout](checkout/main.go) - Check out a specific commit from a repository
+- [log](log/main.go) - Emulate `git log` command output iterating all the commit history from HEAD reference
+- [branch](branch/main.go) - How to create and remove branches or any other kind of reference.
 - [tag](tag/main.go) - List/print repository tags
-- [pull](pull/main.go) - Pull changes from a remote repository
+- [remotes](remotes/main.go) - Working with remotes: adding, removing, etc
+- [progress](progress/main.go) - Printing the progress information from the sideband
 - [revision](revision/main.go) - Solve a revision into a commit
+
 ### Advanced
 - [custom_http](custom_http/main.go) - Replacing the HTTP client using a custom one
+- [clone with context](context/main.go) - Cloning a repository with graceful cancellation.
 - [storage](storage/README.md) - Implementing a custom storage system

_examples/branch/main.go

@@ -0,0 +1,45 @@
+package main
+
+import (
+	"os"
+
+	"gopkg.in/src-d/go-git.v4"
+	. "gopkg.in/src-d/go-git.v4/_examples"
+	"gopkg.in/src-d/go-git.v4/plumbing"
+)
+
+// An example of how to create and remove branches or any other kind of reference.
+func main() {
+	CheckArgs("<url>", "<directory>")
+	url, directory := os.Args[1], os.Args[2]
+
+	// Clone the given repository to the given directory
+	Info("git clone %s %s", url, directory)
+	r, err := git.PlainClone(directory, false, &git.CloneOptions{
+		URL: url,
+	})
+	CheckIfError(err)
+
+	// Create a new branch to the current HEAD
+	Info("git branch my-branch")
+
+	headRef, err := r.Head()
+	CheckIfError(err)
+
+	// Create a new plumbing.HashReference object with the name of the branch
+	// and the hash from the HEAD. The reference name should be a full reference
+	// name and now a abbreviated one, as is used on the git cli.
+	//
+	// For tags we should use `refs/tags/%s` instead of `refs/heads/%s` used
+	// for branches.
+	ref := plumbing.NewHashReference("refs/heads/my-branch", headRef.Hash())
+
+	// The created reference is saved in the storage.
+	err = r.Storer.SetReference(ref)
+	CheckIfError(err)
+
+	// Or deleted from it.
+	Info("git branch -D my-branch")
+	err = r.Storer.RemoveReference(ref.Name())
+	CheckIfError(err)
+}

_examples/branch_add_remove/main.go

@@ -15,19 +15,19 @@ var examplesTest = flag.Bool("examples", false, "run the examples tests")
 var defaultURL = "https://github.com/git-fixtures/basic.git"
 
 var args = map[string][]string{
-	"branch_add_remove": {defaultURL, tempFolder()},
-	"checkout":          {defaultURL, tempFolder(), "35e85108805c84807bc66a02d91535e1e24b38b9"},
-	"clone":             {defaultURL, tempFolder()},
-	"context":           {defaultURL, tempFolder()},
-	"commit":            {cloneRepository(defaultURL, tempFolder())},
-	"custom_http":       {defaultURL},
-	"open":              {cloneRepository(defaultURL, tempFolder())},
-	"progress":          {defaultURL, tempFolder()},
-	"push":              {setEmptyRemote(cloneRepository(defaultURL, tempFolder()))},
-	"revision":          {cloneRepository(defaultURL, tempFolder()), "master~2^"},
-	"showcase":          {defaultURL, tempFolder()},
-	"tag":               {cloneRepository(defaultURL, tempFolder())},
-	"pull":              {createRepositoryWithRemote(tempFolder(), defaultURL)},
+	"branch":      {defaultURL, tempFolder()},
+	"checkout":    {defaultURL, tempFolder(), "35e85108805c84807bc66a02d91535e1e24b38b9"},
+	"clone":       {defaultURL, tempFolder()},
+	"context":     {defaultURL, tempFolder()},
+	"commit":      {cloneRepository(defaultURL, tempFolder())},
+	"custom_http": {defaultURL},
+	"open":        {cloneRepository(defaultURL, tempFolder())},
+	"progress":    {defaultURL, tempFolder()},
+	"push":        {setEmptyRemote(cloneRepository(defaultURL, tempFolder()))},
+	"revision":    {cloneRepository(defaultURL, tempFolder()), "master~2^"},
+	"showcase":    {defaultURL, tempFolder()},
+	"tag":         {cloneRepository(defaultURL, tempFolder())},
+	"pull":        {createRepositoryWithRemote(tempFolder(), defaultURL)},
 }
 
 var ignored = map[string]bool{}