all: Add receive only folder type (#5027)

Adds a receive only folder type that does not send changes, and where the user can optionally revert local changes. Also changes some of the icons to make the three folder types distinguishable.

lib/scanner/walk_test.go

@@ -221,8 +221,8 @@ func TestNormalization(t *testing.T) {
 	// make sure it all gets done. In production, things will be correct
 	// eventually...
 
-	walkDir(testFs, "normalization", nil, nil)
-	tmp := walkDir(testFs, "normalization", nil, nil)
+	walkDir(testFs, "normalization", nil, nil, 0)
+	tmp := walkDir(testFs, "normalization", nil, nil, 0)
 
 	files := fileList(tmp).testfiles()
 
@@ -267,7 +267,7 @@ func TestWalkSymlinkUnix(t *testing.T) {
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, "_symlinks")
 	for _, path := range []string{".", "link"} {
 		// Scan it
-		files := walkDir(fs, path, nil, nil)
+		files := walkDir(fs, path, nil, nil, 0)
 
 		// Verify that we got one symlink and with the correct attributes
 		if len(files) != 1 {
@@ -300,7 +300,7 @@ func TestWalkSymlinkWindows(t *testing.T) {
 
 	for _, path := range []string{".", "link"} {
 		// Scan it
-		files := walkDir(fs, path, nil, nil)
+		files := walkDir(fs, path, nil, nil, 0)
 
 		// Verify that we got zero symlinks
 		if len(files) != 0 {
@@ -329,7 +329,7 @@ func TestWalkRootSymlink(t *testing.T) {
 	}
 
 	// Scan it
-	files := walkDir(fs.NewFilesystem(fs.FilesystemTypeBasic, link), ".", nil, nil)
+	files := walkDir(fs.NewFilesystem(fs.FilesystemTypeBasic, link), ".", nil, nil, 0)
 
 	// Verify that we got two files
 	if len(files) != 2 {
@@ -353,7 +353,7 @@ func TestBlocksizeHysteresis(t *testing.T) {
 	current := make(fakeCurrentFiler)
 
 	runTest := func(expectedBlockSize int) {
-		files := walkDir(sf, ".", current, nil)
+		files := walkDir(sf, ".", current, nil, 0)
 		if len(files) != 1 {
 			t.Fatalf("expected one file, not %d", len(files))
 		}
@@ -407,7 +407,57 @@ func TestBlocksizeHysteresis(t *testing.T) {
 	runTest(512 << 10)
 }
 
-func walkDir(fs fs.Filesystem, dir string, cfiler CurrentFiler, matcher *ignore.Matcher) []protocol.FileInfo {
+func TestWalkReceiveOnly(t *testing.T) {
+	sf := fs.NewWalkFilesystem(&singleFileFS{
+		name:     "testfile.dat",
+		filesize: 1024,
+	})
+
+	current := make(fakeCurrentFiler)
+
+	// Initial scan, no files in the CurrentFiler. Should pick up the file and
+	// set the ReceiveOnly flag on it, because that's the flag we give the
+	// walker to set.
+
+	files := walkDir(sf, ".", current, nil, protocol.FlagLocalReceiveOnly)
+	if len(files) != 1 {
+		t.Fatal("Should have scanned one file")
+	}
+
+	if files[0].LocalFlags != protocol.FlagLocalReceiveOnly {
+		t.Fatal("Should have set the ReceiveOnly flag")
+	}
+
+	// Update the CurrentFiler and scan again. It should not return
+	// anything, because the file has not changed. This verifies that the
+	// ReceiveOnly flag is properly ignored and doesn't trigger a rescan
+	// every time.
+
+	cur := files[0]
+	current[cur.Name] = cur
+
+	files = walkDir(sf, ".", current, nil, protocol.FlagLocalReceiveOnly)
+	if len(files) != 0 {
+		t.Fatal("Should not have scanned anything")
+	}
+
+	// Now pretend the file was previously ignored instead. We should pick up
+	// the difference in flags and set just the LocalReceive flags.
+
+	cur.LocalFlags = protocol.FlagLocalIgnored
+	current[cur.Name] = cur
+
+	files = walkDir(sf, ".", current, nil, protocol.FlagLocalReceiveOnly)
+	if len(files) != 1 {
+		t.Fatal("Should have scanned one file")
+	}
+
+	if files[0].LocalFlags != protocol.FlagLocalReceiveOnly {
+		t.Fatal("Should have set the ReceiveOnly flag")
+	}
+}
+
+func walkDir(fs fs.Filesystem, dir string, cfiler CurrentFiler, matcher *ignore.Matcher, localFlags uint32) []protocol.FileInfo {
 	fchan := Walk(context.TODO(), Config{
 		Filesystem:     fs,
 		Subs:           []string{dir},
@@ -416,6 +466,7 @@ func walkDir(fs fs.Filesystem, dir string, cfiler CurrentFiler, matcher *ignore.
 		UseLargeBlocks: true,
 		CurrentFiler:   cfiler,
 		Matcher:        matcher,
+		LocalFlags:     localFlags,
 	})
 
 	var tmp []protocol.FileInfo
@@ -579,7 +630,7 @@ func TestIssue4799(t *testing.T) {
 	}
 	fd.Close()
 
-	files := walkDir(fs, "/foo", nil, nil)
+	files := walkDir(fs, "/foo", nil, nil, 0)
 	if len(files) != 1 || files[0].Name != "foo" {
 		t.Error(`Received unexpected file infos when walking "/foo"`, files)
 	}
@@ -597,7 +648,7 @@ func TestRecurseInclude(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	files := walkDir(testFs, ".", nil, ignores)
+	files := walkDir(testFs, ".", nil, ignores, 0)
 
 	expected := []string{
 		filepath.Join("dir1"),