Add commit logs to PR message

exec_cmd.go

+package main
+
+import (
+	"os/exec"
+)
+
+type ExecCmd struct {
+	Name string
+	Args []string
+}
+
+func (cmd *ExecCmd) WithArg(arg string) *ExecCmd {
+	cmd.Args = append(cmd.Args, arg)
+
+	return cmd
+}
+
+func (cmd *ExecCmd) Exec() (out string, err error) {
+	output, err := exec.Command(cmd.Name, cmd.Args...).Output()
+	if err != nil {
+		return "", err
+	}
+
+	return string(output), nil
+}
+
+func NewExecCmd(name string) *ExecCmd {
+	return &ExecCmd{name, make([]string, 0)}
+}

exec_cmd_test.go

+package main
+
+import (
+	"github.com/bmizerany/assert"
+	"testing"
+)
+
+func TestWithArg(t *testing.T) {
+	execCmd := NewExecCmd("git")
+	execCmd.WithArg("log").WithArg("--no-color")
+	assert.Equal(t, "git", execCmd.Name)
+	assert.Equal(t, 2, len(execCmd.Args))
+}

git.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"fmt"
 	"log"
 	"os/exec"
 	"path/filepath"
@@ -41,6 +42,22 @@ func (g *Git) CurrentBranch() string {
 	return execGitCmd("symbolic-ref -q --short HEAD")[0]
 }
 
+func (g *Git) CommitLogs(sha1, sha2 string) string {
+	execCmd := NewExecCmd("git")
+	execCmd.WithArg("log").WithArg("--no-color")
+	execCmd.WithArg("--format=%h (%aN, %ar)%n%w(78,3,3)%s%n%+b")
+	execCmd.WithArg("--cherry")
+	shaRange := fmt.Sprintf("%s...%s", sha1, sha2)
+	execCmd.WithArg(shaRange)
+
+	outputs, err := execCmd.Exec()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	return outputs
+}
+
 // FIXME: only care about origin push remote now
 func (g *Git) Remote() string {
 	r := regexp.MustCompile("origin\t(.+) \\(push\\)")

git_test.go

@@ -13,4 +13,6 @@ func TestGitMethods(t *testing.T) {
 	assert.Equal(t, "jingweno", git.Owner())
 	assert.Equal(t, "gh", git.Repo())
 	assert.Equal(t, "pull_request", git.CurrentBranch())
+	logs := git.CommitLogs("master", "HEAD")
+	assert.Equal(t, 19, len(logs))
 }

pull_request.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"bufio"
+	"fmt"
 	"io/ioutil"
 	"log"
 	"os"
@@ -43,7 +44,7 @@ func init() {
 func pullRequest(cmd *Command, args []string) {
 	messageFile := filepath.Join(git.Dir(), "PULLREQ_EDITMSG")
 
-	writePullRequestChanges(messageFile)
+	writePullRequestChanges(messageFile, flagPullRequestBase, flagPullRequestHead)
 
 	editCmd := buildEditCommand(messageFile)
 	err := execCmd(editCmd)
@@ -66,9 +67,26 @@ func pullRequest(cmd *Command, args []string) {
 	}
 }
 
-func writePullRequestChanges(messageFile string) {
-	message := []byte("\n#\n# Changes:\n#")
-	err := ioutil.WriteFile(messageFile, message, 0644)
+func writePullRequestChanges(messageFile, base, head string) {
+	message := `
+# Requesting a pull to %s from %s
+#
+# Write a message for this pull reuqest. The first block
+# of the text is the title and the rest is description.
+#
+# Changes:
+#
+%s
+`
+	startRegexp := regexp.MustCompilePOSIX("^")
+	endRegexp := regexp.MustCompilePOSIX(" +$")
+
+	commitLogs := git.CommitLogs("master", "pull_request")
+	commitLogs = startRegexp.ReplaceAllString(commitLogs, "# ")
+	commitLogs = endRegexp.ReplaceAllString(commitLogs, "")
+
+	message = fmt.Sprintf(message, base, head, commitLogs)
+	err := ioutil.WriteFile(messageFile, []byte(message), 0644)
 	if err != nil {
 		log.Fatal(err)
 	}