From cafabc99f6b4df013d939b0109af1d3fb6424597 Mon Sep 17 00:00:00 2001
From: Zach Klippenstein <zach.klippenstein@gmail.com>
Date: Sun, 3 May 2015 08:12:53 -0700
Subject: [PATCH] Detect non-existent paths in sync_client, tests for
 sync_client#stat.

---
 sync_client.go      | 10 ++++++++
 sync_client_test.go | 56 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+)

diff --git a/sync_client.go b/sync_client.go
index 92b53d9..ac40470 100644
--- a/sync_client.go
+++ b/sync_client.go
@@ -4,10 +4,14 @@ package goadb
 import (
 	"fmt"
 	"io"
+	"os"
+	"time"
 
 	"github.com/zach-klippenstein/goadb/wire"
 )
 
+var zeroTime = time.Unix(0, 0).UTC()
+
 func stat(conn *wire.SyncConn, path string) (*DirEntry, error) {
 	if err := conn.SendOctetString("STAT"); err != nil {
 		return nil, err
@@ -66,6 +70,12 @@ func readStat(s wire.SyncScanner) (entry *DirEntry, err error) {
 		return
 	}
 
+	// adb doesn't indicate when a file doesn't exist, but will return all zeros.
+	// Theoretically this could be an actual file, but that's very unlikely.
+	if mode == os.FileMode(0) && size == 0 && mtime == zeroTime {
+		return nil, os.ErrNotExist
+	}
+
 	entry = &DirEntry{
 		Mode:       mode,
 		Size:       size,
diff --git a/sync_client_test.go b/sync_client_test.go
index d1fde95..f01220b 100644
--- a/sync_client_test.go
+++ b/sync_client_test.go
@@ -1,2 +1,58 @@
 // TODO(z): Implement tests for sync_client functions.
 package goadb
+
+import (
+	"bytes"
+	"os"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/zach-klippenstein/goadb/wire"
+)
+
+var someTime = time.Date(2015, 5, 3, 8, 8, 8, 0, time.UTC)
+
+func TestStatValid(t *testing.T) {
+	var buf bytes.Buffer
+	conn := &wire.SyncConn{wire.NewSyncScanner(&buf), wire.NewSyncSender(&buf)}
+
+	var mode os.FileMode = 0777
+
+	conn.SendOctetString("STAT")
+	conn.SendFileMode(mode)
+	conn.SendInt32(4)
+	conn.SendTime(someTime)
+
+	entry, err := stat(conn, "/thing")
+	assert.NoError(t, err)
+	assert.Equal(t, mode, entry.Mode, "expected os.FileMode %s, got %s", mode, entry.Mode)
+	assert.Equal(t, 4, entry.Size)
+	assert.Equal(t, someTime, entry.ModifiedAt)
+	assert.Equal(t, "", entry.Name)
+}
+
+func TestStatBadResponse(t *testing.T) {
+	var buf bytes.Buffer
+	conn := &wire.SyncConn{wire.NewSyncScanner(&buf), wire.NewSyncSender(&buf)}
+
+	conn.SendOctetString("SPAT")
+
+	entry, err := stat(conn, "/")
+	assert.Nil(t, entry)
+	assert.Error(t, err)
+}
+
+func TestStatNoExist(t *testing.T) {
+	var buf bytes.Buffer
+	conn := &wire.SyncConn{wire.NewSyncScanner(&buf), wire.NewSyncSender(&buf)}
+
+	conn.SendOctetString("STAT")
+	conn.SendFileMode(0)
+	conn.SendInt32(0)
+	conn.SendTime(time.Unix(0, 0).UTC())
+
+	entry, err := stat(conn, "/")
+	assert.Nil(t, entry)
+	assert.Equal(t, os.ErrNotExist, err)
+}