build: adjust file sync server (#6104)

the sync protocol should always send over the directory
file info when it sends over files in its subtree, even
if the directory path itself is marked as ignored

fixes #6102

Signed-off-by: Nick Santos <nick.santos@docker.com>

integration/ignores/.dockerignore

@@ -1 +1,3 @@
-ignored_by_dockerignore.txt
+ignored_by_dockerignore.txt
+topdir
+!topdir/subdir

integration/ignores/topdir/subdir/src.txt

@@ -0,0 +1 @@
+hello world

integration/ignores_test.go

@@ -48,4 +48,8 @@ func TestIgnores(t *testing.T) {
 	res, err = http.Get("http://localhost:31234/ignored_by_tiltfile.txt")
 	assert.NoError(t, err)
 	assert.Equal(t, res.StatusCode, http.StatusNotFound)
+
+	_, body, err = f.Curl("http://localhost:31234/topdir/subdir/src.txt")
+	assert.NoError(t, err)
+	assert.Contains(t, body, "hello")
 }

internal/build/docker_builder.go

@@ -566,16 +566,17 @@ func toSyncedDirs(context string, dockerfileSyncDir string, filter model.PathMat
 			path = filepath.Join(context, path)
 		}
 
-		matches, _ := filter.Matches(path)
-		if matches {
-			isDir := s != nil && s.IsDir()
-			if isDir {
-				entireDir, _ := filter.MatchesEntireDir(path)
-				if entireDir {
-					return fsutil.MapResultSkipDir
-				}
+		isDir := s != nil && s.IsDir()
+		if isDir {
+			entireDir, _ := filter.MatchesEntireDir(path)
+			if entireDir {
+				return fsutil.MapResultSkipDir
+			}
+		} else {
+			matches, _ := filter.Matches(path)
+			if matches {
+				return fsutil.MapResultExclude
 			}
-			return fsutil.MapResultExclude
 		}
 		s.Uid = 0
 		s.Gid = 0