commands/git : returns an error instead of panicing

pkg/commands/git.go

@@ -499,12 +499,8 @@ func (c *GitCommand) Ignore(filename string) error {
 }
 
 // Show shows the diff of a commit
-func (c *GitCommand) Show(sha string) string {
+func (c *GitCommand) Show(sha string) (string, error) {
-	result, err := c.OSCommand.RunCommandWithOutput("git show --color " + sha)
+	return c.OSCommand.RunCommandWithOutput(fmt.Sprintf("git show --color %s", sha))
-	if err != nil {
-		panic(err)
-	}
-	return result
 }
 
 // Diff returns the diff of a file

pkg/commands/git_test.go

@@ -1421,6 +1421,19 @@ func TestGitCommandRemoveFile(t *testing.T) {
 	}
 }
 
+func TestGitCommandShow(t *testing.T) {
+	gitCmd := newDummyGitCommand()
+	gitCmd.OSCommand.command = func(cmd string, args ...string) *exec.Cmd {
+		assert.EqualValues(t, "git", cmd)
+		assert.EqualValues(t, []string{"show", "--color", "456abcde"}, args)
+
+		return exec.Command("echo")
+	}
+
+	_, err := gitCmd.Show("456abcde")
+	assert.NoError(t, err)
+}
+
 func TestGitCommandCheckout(t *testing.T) {
 	type scenario struct {
 		testName string

pkg/gui/commits_panel.go

@@ -68,7 +68,10 @@ func (gui *Gui) handleCommitSelect(g *gocui.Gui, v *gocui.View) error {
 		}
 		return gui.renderString(g, "main", gui.Tr.SLocalize("NoCommitsThisBranch"))
 	}
-	commitText := gui.GitCommand.Show(commit.Sha)
+	commitText, err := gui.GitCommand.Show(commit.Sha)
+	if err != nil {
+		return err
+	}
 	return gui.renderString(g, "main", commitText)
 }