Simplify the building of a note path

This also sneakily fixes the problem where I forgot to add a slash
to these paths because trailing slashes are stripped since #5a5c407.

notes.go

@@ -79,7 +79,7 @@ func showNote(params ...string) {
 		query = params[1]
 	}
 
-	path := fmt.Sprintf("%v%v.txt", getNotesDir(), note)
+	path := getNote(note)
 	file, err := os.Open(path)
 	if err != nil {
 		// File does not exist, create it
@@ -129,9 +129,9 @@ func colorizeComment(line string) {
 }
 
 func editOrCreateNote(note string) {
-	file := fmt.Sprintf("%v%v.txt", getNotesDir(), note)
+	path := getNote(note)
 
-	command := exec.Command(getEditor(), file)
+	command := exec.Command(getEditor(), path)
 	command.Stdin = os.Stdin
 	command.Stdout = os.Stdout
 	command.Stderr = os.Stderr
@@ -162,6 +162,11 @@ func getNotesDir() string {
 	return filepath.Clean(dir)
 }
 
+// getNote returns the path to the note given
+func getNote(path string) string {
+	return fmt.Sprintf("%s/%s.txt", getNotesDir(), path)
+}
+
 func main() {
 	app := cli.NewApp()
 	app.Name = "notes"

notes_test.go

@@ -1,12 +1,20 @@
 package main
 
 import (
+	"log"
 	"os"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 )
 
+func init() {
+	err := os.Setenv("HOME", "/home/testuser")
+	if err != nil {
+		log.Fatalf("Setenv failed")
+	}
+}
+
 func TestGetEditorDefault(t *testing.T) {
 	expected := "vi"
 	outcome := getEditor()
@@ -24,10 +32,6 @@ func TestGetEditorWithEnvVariable(t *testing.T) {
 }
 
 func TestGetNotesDir(t *testing.T) {
-	err := os.Setenv("HOME", "/home/testuser")
-	if err != nil {
-		t.Fatalf("Setenv failed")
-	}
 	expected := "/home/testuser/dotfiles/notes"
 	outcome := getNotesDir()
 	assert.Equal(t, expected, outcome)
@@ -41,6 +45,8 @@ func TestGetNotesDirWithCustomEnvVariable(t *testing.T) {
 	expected := "/some/other/path"
 	outcome := getNotesDir()
 	assert.Equal(t, expected, outcome)
+
+	_ = os.Unsetenv("NOTESDIR")
 }
 
 func TestGetNotesDirUsesCustomEnvVariableOverHomeEnvVariable(t *testing.T) {
@@ -55,6 +61,8 @@ func TestGetNotesDirUsesCustomEnvVariableOverHomeEnvVariable(t *testing.T) {
 	expected := "/some/other/path"
 	outcome := getNotesDir()
 	assert.Equal(t, expected, outcome)
+
+	_ = os.Unsetenv("NOTESDIR")
 }
 
 func TestGetNotesDirUsesCustomEnvVariableWithoutTrailingSlash(t *testing.T) {
@@ -65,6 +73,8 @@ func TestGetNotesDirUsesCustomEnvVariableWithoutTrailingSlash(t *testing.T) {
 	expected := "/some/other/path"
 	outcome := getNotesDir()
 	assert.Equal(t, expected, outcome)
+
+	_ = os.Unsetenv("NOTESDIR")
 }
 
 func TestFindNotes(t *testing.T) {
@@ -108,3 +118,9 @@ func TestFindNotesCaseInsensitivity(t *testing.T) {
 	result := findNotes(notes, "match")
 	assert.Equal(t, 1, len(result))
 }
+
+func TestGetNote(t *testing.T) {
+	expected := "/home/testuser/dotfiles/notes/git.txt"
+	outcome := getNote("git")
+	assert.Equal(t, expected, outcome)
+}