[in] creates file 'tag' containing git tag for the release being fetched

README.md

@@ -28,6 +28,8 @@ Fetches artifacts from the given release version. If the version is not
 specified, the latest version is chosen using [semver](http://semver.org)
 semantics.
 
+Creates a file `tag` containing the tag name/version of the release being fetched.
+
 #### Parameters
 
 * `globs`: *Optional.* A list of globs for files that will be downloaded from

in_command.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net/http"
 	"os"
 	"path/filepath"
@@ -58,6 +59,12 @@ func (c *InCommand) Run(destDir string, request InRequest) (InResponse, error) {
 		return InResponse{}, fmt.Errorf("could not find release with tag: %s", request.Version.Tag)
 	}
 
+	tagPath := filepath.Join(destDir, "tag")
+	err = ioutil.WriteFile(tagPath, []byte(*foundRelease.TagName), 0644)
+	if err != nil {
+		return InResponse{}, err
+	}
+
 	assets, err := c.github.ListReleaseAssets(foundRelease)
 	if err != nil {
 		return InResponse{}, err

in_command_test.go

@@ -236,6 +236,16 @@ var _ = Describe("In Command", func() {
 				))
 			})
 
+			It("stores tag in a file", func() {
+				_, err := os.Stat(filepath.Join(destDir, "tag"))
+				Ω(err).ShouldNot(HaveOccurred())
+
+				tag, err := ioutil.ReadFile(filepath.Join(destDir, "tag"))
+				Ω(err).ShouldNot(HaveOccurred())
+
+				Ω(string(tag)).Should(Equal("v0.35.0"))
+			})
+
 			It("fetches from the latest release", func() {
 				_, err := os.Stat(filepath.Join(destDir, "example.txt"))
 				Ω(err).ShouldNot(HaveOccurred())