Read cached file in editor if it exists

github/editor.go

@@ -27,46 +27,67 @@ func NewEditor(filePrefix, topic, message string) (editor *Editor, err error) {
 	}
 
 	editor = &Editor{
-		Program: program,
-		Topic:   topic,
-		File:    messageFile,
-		Message: message,
-		doEdit:  doTextEditorEdit,
+		Program:    program,
+		Topic:      topic,
+		File:       messageFile,
+		Message:    message,
+		openEditor: doTextEditorEdit,
 	}
 
 	return
 }
 
 type Editor struct {
-	Program string
-	Topic   string
-	File    string
-	Message string
-	doEdit  func(program, file string) error
+	Program    string
+	Topic      string
+	File       string
+	Message    string
+	openEditor func(program, file string) error
 }
 
-func (e *Editor) Edit() (content []byte, err error) {
-	if e.Message != "" {
+func (e *Editor) isFileExist() bool {
+	_, err := os.Stat(e.File)
+	return err == nil || !os.IsNotExist(err)
+}
+
+func (e *Editor) WriteContent() (err error) {
+	// only write message if file doesn't exist
+	if !e.isFileExist() && e.Message != "" {
 		err = ioutil.WriteFile(e.File, []byte(e.Message), 0644)
 		if err != nil {
 			return
 		}
 	}
+
+	return
+}
+
+func (e *Editor) readContent() (content []byte, err error) {
+	return ioutil.ReadFile(e.File)
+}
+
+func (e *Editor) openAndEdit() (content []byte, err error) {
+	err = e.WriteContent()
+	if err != nil {
+		return
+	}
+
+	// always remove file after editing is done
 	defer os.Remove(e.File)
 
-	err = e.doEdit(e.Program, e.File)
+	err = e.openEditor(e.Program, e.File)
 	if err != nil {
 		err = fmt.Errorf("error using text editor for %s message", e.Topic)
 		return
 	}
 
-	content, err = ioutil.ReadFile(e.File)
+	content, err = e.readContent()
 
 	return
 }
 
 func (e *Editor) EditTitleAndBody() (title, body string, err error) {
-	content, err := e.Edit()
+	content, err := e.openAndEdit()
 	if err != nil {
 		return
 	}

github/editor_test.go

@@ -2,27 +2,30 @@ package github
 
 import (
 	"bufio"
-	"github.com/bmizerany/assert"
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"strings"
 	"testing"
+
+	"github.com/bmizerany/assert"
 )
 
-func TestEditor_Edit(t *testing.T) {
+func TestEditor_openAndEdit_fileExist(t *testing.T) {
 	tempFile, _ := ioutil.TempFile("", "editor-test")
+	ioutil.WriteFile(tempFile.Name(), []byte("hello"), 0644)
 	editor := Editor{
 		Program: "memory",
 		File:    tempFile.Name(),
-		doEdit: func(program string, file string) error {
+		openEditor: func(program string, file string) error {
 			assert.Equal(t, "memory", program)
 			assert.Equal(t, tempFile.Name(), file)
 
-			return ioutil.WriteFile(file, []byte("hello"), 0644)
+			return nil
 		},
 	}
 
-	content, err := editor.Edit()
+	content, err := editor.openAndEdit()
 	assert.Equal(t, nil, err)
 	assert.Equal(t, "hello", string(content))
 
@@ -31,14 +34,38 @@ func TestEditor_Edit(t *testing.T) {
 	assert.T(t, os.IsNotExist(err))
 }
 
-func TestEditor_EditTitleAndBody(t *testing.T) {
-	tempFile, _ := ioutil.TempFile("", "editor-test")
+func TestEditor_openAndEdit_fileNotExist(t *testing.T) {
+	tempDir, _ := ioutil.TempDir("", "editor-test")
+	tempFile := filepath.Join(tempDir, "PULLREQ")
 	editor := Editor{
 		Program: "memory",
-		File:    tempFile.Name(),
-		doEdit: func(program string, file string) error {
+		File:    tempFile,
+		openEditor: func(program string, file string) error {
 			assert.Equal(t, "memory", program)
-			assert.Equal(t, tempFile.Name(), file)
+			assert.Equal(t, tempFile, file)
+
+			return ioutil.WriteFile(file, []byte("hello"), 0644)
+		},
+	}
+
+	content, err := editor.openAndEdit()
+	assert.Equal(t, nil, err)
+	assert.Equal(t, "hello", string(content))
+
+	// file is removed after edit
+	_, err = os.Stat(tempFile)
+	assert.T(t, os.IsNotExist(err))
+}
+
+func TestEditor_EditTitleAndBody(t *testing.T) {
+	tempDir, _ := ioutil.TempDir("", "editor-test")
+	tempFile := filepath.Join(tempDir, "PULLREQ")
+	editor := Editor{
+		Program: "memory",
+		File:    tempFile,
+		openEditor: func(program string, file string) error {
+			assert.Equal(t, "memory", program)
+			assert.Equal(t, tempFile, file)
 
 			message := `A title
 A title continues
@@ -57,7 +84,7 @@ A body continues
 	assert.Equal(t, "A body\nA body continues", body)
 
 	// file is removed after edit
-	_, err = os.Stat(tempFile.Name())
+	_, err = os.Stat(tempFile)
 	assert.T(t, os.IsNotExist(err))
 }