Basic git show command

cmd/flag.go

@@ -0,0 +1,30 @@
+package cmd
+
+import (
+	"fmt"
+)
+
+// A string value compatible with a flag var
+//  that allows you to assign multiple flags
+//  to the same string value. If the value is
+//  set twice either by duplicating the flag
+//  or using the original and alias then an error
+//  is raised.
+type aliasedStringValue string
+
+func newAliasedStringValue(p *string, val string) *aliasedStringValue {
+	*p = val
+	return (*aliasedStringValue)(p)
+}
+
+func (s *aliasedStringValue) Set(val string) error {
+	if *s != "" {
+		return fmt.Errorf("Value already set to %v", val)
+	}
+	*s = aliasedStringValue(val)
+	return nil
+}
+
+func (s *aliasedStringValue) Get() interface{} { return string(*s) }
+
+func (s *aliasedStringValue) String() string { return string(*s) }

cmd/show.go

@@ -0,0 +1,26 @@
+package cmd
+
+import (
+	"flag"
+	"fmt"
+
+	"github.com/driusan/dgit/git"
+)
+
+func Show(c *git.Client, args []string) error {
+	flags := flag.NewFlagSet("show", flag.ExitOnError)
+	flags.SetOutput(flag.CommandLine.Output())
+	flags.Usage = func() {
+		flag.Usage()
+		fmt.Fprintf(flag.CommandLine.Output(), "\n\nOptions:\n")
+		flags.PrintDefaults()
+	}
+
+	opts := git.ShowOptions{}
+	flags.Var(newAliasedStringValue((*string)(&opts.Format), ""), "format", "Print the contents of commit logs in a specified format")
+	flags.Var(newAliasedStringValue((*string)(&opts.Format), ""), "pretty", "Alias for --format")
+	flags.Parse(args)
+
+	objects := flags.Args()
+	return git.Show(c, opts, objects)
+}

git/show.go

@@ -0,0 +1,90 @@
+package git
+
+import (
+	"fmt"
+	"strings"
+)
+
+type FormatString string
+
+func (f FormatString) FormatCommit(c *Client, cmt CommitID) (string, error) {
+	if f == "" || f == "medium" {
+		output, err := formatCommitMedium(cmt, c)
+		if err != nil {
+			return "", err
+		}
+		return fmt.Sprintf("%v\n", output), nil
+	}
+	if f == "raw" {
+		output := fmt.Sprintf("commit %v\n", cmt)
+		cmtObject, err := c.GetCommitObject(cmt)
+		if err != nil {
+			return "", err
+		}
+		return fmt.Sprintf("%v%v\n", output, cmtObject), nil
+	}
+
+	return "", fmt.Errorf("Format %s is not supported.\n", f)
+}
+
+type ShowOptions struct {
+	DiffOptions
+	Format FormatString
+}
+
+// Show implementes the "git show" command.
+func Show(c *Client, opts ShowOptions, objects []string) error {
+	if len(objects) < 1 {
+		return fmt.Errorf("Provide at least one commit.")
+	}
+
+	commitIds := []CommitID{}
+
+	for _, object := range objects {
+		// Commits only for now
+		commit, err := RevParseCommit(c, &RevParseOptions{}, object)
+		if err != nil {
+			return err
+		}
+
+		commitIds = append(commitIds, commit)
+	}
+
+	for _, commit := range commitIds {
+		output, err := opts.Format.FormatCommit(c, commit)
+		if err != nil {
+			return err
+		}
+		fmt.Printf("%v", output)
+	}
+
+	return nil
+}
+
+func formatCommitMedium(cmt CommitID, c *Client) (string, error) {
+	author, err := cmt.GetAuthor(c)
+	if err != nil {
+		return "", err
+	}
+
+	date, err := cmt.GetDate(c)
+	if err != nil {
+		return "", err
+	}
+
+	msg, err := cmt.GetCommitMessage(c)
+	if err != nil {
+		return "", err
+	}
+
+	// Headers
+	output := fmt.Sprintf("commit %v\nAuthor: %s\nDate: %v\n\n", cmt, author, date.Format("Mon Jan 2 15:04:05 2006 -0700"))
+
+	// Commit message body
+	lines := strings.Split(strings.TrimSpace(msg.String()), "\n")
+	for _, l := range lines {
+		output = fmt.Sprintf("%v    %v\n", output, l)
+	}
+
+	return output, nil
+}

main.go

@@ -307,6 +307,12 @@ func main() {
 			fmt.Fprintln(os.Stderr, err)
 			os.Exit(4)
 		}
+	case "show":
+		subcommandUsage = "<commit>..."
+		if err := cmd.Show(c, args); err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(4)
+		}
 	case "help":
 		flag.CommandLine.SetOutput(os.Stdout)
 		flag.Usage()
@@ -353,6 +359,7 @@ func main() {
    apply
    revert
    help
+   show             Show various types of objects
 `)
 
 		os.Exit(0)

status.txt

@@ -44,7 +44,7 @@ reset          Almost        git 2.9.2              -N not parsed, -p, --merge,
 revert         HappyPath     git 2.14.2	     (6) Sequencer options (--continue/quit/abort) are missing, can only do 1 revert at a time. GPG not implemented. MergeStrategy not implemented. --signoff passed to commit, but commit doesn't implement.
 rm             None                                 Can use rm; git add instead.
 shortlog       None
-show           None
+show           HappyPath     git 2.18.0             only commits (no special merge commit format), only --pretty=raw and standard
 stash          None
 status         HappyPath     git 2.14.2              (6.5) missing --show-stash, --porcelain=2, -v, -v -v, --ignore-submodules, --ignored, --column/--no-column
 submodule      None