fix attr bitmasks: match ultraviolet (RapidBlink/Conceal shifted Reverse/Strike)

cmd/mosh-wasm/state.go

@@ -60,11 +60,13 @@ func (st *stateTracker) applyDiff(diff []byte, oldNum, newNum uint64) {
 	// Need the base state to apply the diff.
 	base, ok := st.states[oldNum]
 	if !ok {
-		return
+		// After a resize we have no states. Start fresh with a
-	}
+		// clean emulator so the first post-resize diff works.
-
+		st.shadow = vt.NewEmulator(st.cols, st.rows)
-	// Restore shadow to base state if needed.
+		st.shadowState = oldNum
-	if st.shadowState != oldNum {
+		base = mosh.SnapshotEmulator(st.shadow, true)
+		st.states[oldNum] = base
+	} else if st.shadowState != oldNum {
 		st.shadow = vt.NewEmulator(st.cols, st.rows)
 		// Write the base framebuffer as ANSI to restore state.
 		if base != nil {

framebuffer.go

@@ -15,8 +15,10 @@ const (
 	attrFaint         = 1 << 1
 	attrItalic        = 1 << 2
 	attrBlink         = 1 << 3
-	attrReverse       = 1 << 4
+	attrRapidBlink    = 1 << 4
-	attrStrikethrough = 1 << 5
+	attrReverse       = 1 << 5
+	attrConceal       = 1 << 6
+	attrStrikethrough = 1 << 7
 )
 
 // Framebuffer represents a terminal screen state for mosh SSP.
@@ -172,11 +174,11 @@ func (fb *Framebuffer) fullRedraw() []byte {
 			buf = append(buf, "\r\n"...)
 		}
 		rowOff := y * fb.W
-		// Track trailing spaces to avoid sending them.
+		// Track trailing default-attr spaces to avoid sending them.
 		lastNonSpace := -1
 		for x := fb.W - 1; x >= 0; x-- {
 			c := &fb.Cells[rowOff+x]
-			if c.Rune != ' ' || c.Rune == 0 || c.Attr != (Attr{}) {
+			if (c.Rune != ' ' && c.Rune != 0) || c.Attr != (Attr{}) {
 				lastNonSpace = x
 				break
 			}