chore: Proper error handling and add few unit tests

pkg/client/metadata.go

@@ -22,11 +22,11 @@ type TagInfo struct {
 func GitMetadata(appPath string) *platform.ProjectSource {
 	repo, err := git.PlainOpen(appPath)
 	if err != nil {
-		print("unable to open git repo")
+		return nil
 	}
 	headRef, err := repo.Head()
 	if err != nil {
-		print("unable to parse head")
+		return nil
 	}
 	commitTagMap := generateTagsMap(repo)
 
@@ -112,7 +112,7 @@ func parseGitDescribe(repo *git.Repository, headRef *plumbing.Reference, commitT
 	}
 	commits, err := repo.Log(logOpts)
 	if err != nil {
-		print("no commits found")
+		return ""
 	}
 
 	latestTag := headRef.Hash().String()

pkg/client/metadata_test.go

@@ -10,14 +10,16 @@ import (
 	"testing"
 	"time"
 
-	h "github.com/buildpacks/pack/testhelpers"
+	"github.com/buildpacks/lifecycle/platform"
 	"github.com/go-git/go-git/v5"
 	"github.com/go-git/go-git/v5/config"
 	"github.com/go-git/go-git/v5/plumbing"
 	"github.com/go-git/go-git/v5/plumbing/object"
 	"github.com/heroku/color"
 	"github.com/sclevine/spec"
 	"github.com/sclevine/spec/report"
+
+	h "github.com/buildpacks/pack/testhelpers"
 )
 
 func TestMetadata(t *testing.T) {
@@ -49,6 +51,37 @@ func testMetadata(t *testing.T, when spec.G, it spec.S) {
 		h.AssertNil(t, os.RemoveAll(repoPath))
 	})
 
+	when("#GitMetadata", func() {
+		it("returns proper metadata format", func() {
+			assert := h.NewAssertionManager(t)
+			remoteOpts := &config.RemoteConfig{
+				Name: "origin",
+				URLs: []string{"git@github.com:testorg/testproj.git", "git@github.com:testorg/testproj.git"},
+			}
+			repo.CreateRemote(remoteOpts)
+			createUnannotatedTag(t, repo, commits[len(commits)-1], "testTag")
+
+			output := GitMetadata(repoPath)
+			expectedOutput := &platform.ProjectSource{
+				Type: "git",
+				Version: map[string]interface{}{
+					"commit":   commits[len(commits)-1].String(),
+					"describe": "testTag",
+				},
+				Metadata: map[string]interface{}{
+					"refs": []string{"master", "testTag"},
+					"url":  "git@github.com:testorg/testproj.git",
+				},
+			}
+			assert.Equal(output, expectedOutput)
+		})
+
+		it("returns nil if error occurs while fetching metadata", func() {
+			output := GitMetadata("/git-path-not-found-ok")
+			h.AssertNil(t, output)
+		})
+	})
+
 	when("#generateTagsMap", func() {
 		when("repository has no tags", func() {
 			it("returns empty map", func() {
@@ -396,7 +429,6 @@ func testMetadata(t *testing.T, when spec.G, it spec.S) {
 						h.AssertEq(t, output, expectedOutput)
 					})
 				})
-
 			})
 		})
 	})
@@ -554,6 +586,13 @@ func testMetadata(t *testing.T, when spec.G, it spec.S) {
 			h.AssertEq(t, output, "git@fetch.com:testorg/testproj.git")
 		})
 	})
+
+	when("#getRefName", func() {
+		it("return proper ref for refs with `/`", func() {
+			output := getRefName("refs/tags/this/is/a/tag/with/slashes")
+			h.AssertEq(t, output, "this/is/a/tag/with/slashes")
+		})
+	})
 }
 
 func createCommits(t *testing.T, repo *git.Repository, repoPath string, numberOfCommits int) []plumbing.Hash {