Ignore graphemes of width 0 when writing to buffer

examples/text_wrapping.rs

@@ -10,8 +10,8 @@ fn draw(f: &mut Frame) {
         "After this sentence come two newlines, so it should always break here.\n",
         "\n",
         "Since the wrapping algorithm is aware of the Unicode Standard Annex #14, ",
-        "it understands things like nonbreaking spaces: ",
-        "This\u{00a0}sentence\u{00a0}is\u{00a0}separated\u{00a0}by\u{00a0}nonbreaking\u{00a0}spaces.\n",
+        "it understands things like non-breaking spaces and word joiners: ",
+        "This\u{00a0}sentence\u{00a0}is\u{00a0}separated\u{00a0}by\u{00a0}non-\u{2060}breaking\u{00a0}spaces.\n",
         "\n",
         "It can also properly handle wide graphemes (like emoji 🤔), ",
         "including ones usually displayed incorrectly by terminal emulators, like 👩‍🔬 (a female scientist emoji).",

src/buffer.rs

@@ -142,7 +142,9 @@ impl Buffer {
 
         for grapheme in content.graphemes(true) {
             let width = widthdb.grapheme_width(grapheme);
-            self.write_grapheme(pos.x, y, width, grapheme, style);
+            if width > 0 {
+                self.write_grapheme(pos.x, y, width, grapheme, style);
+            }
             pos.x += width as i32;
         }
     }

src/widthdb.rs

@@ -65,7 +65,7 @@ impl WidthDB {
                 .queue(MoveTo(0, 0))?
                 .queue(Print(&grapheme))?;
             out.flush()?;
-            let width = crossterm::cursor::position()?.0.max(1) as u8;
+            let width = crossterm::cursor::position()?.0 as u8;
             self.known.insert(grapheme, width);
         }
         Ok(())