Merge pull request #526 from tertsdiepraam/ansi-hyperlink

`display_width`: ignore ANSI hyperlinks in width calculation

src/core.rs

@@ -46,13 +46,28 @@ const ANSI_FINAL_BYTE: std::ops::RangeInclusive<char> = '\x40'..='\x7e';
 /// modified if `ch` is the start of an ANSI escape sequence.
 #[inline]
 pub(crate) fn skip_ansi_escape_sequence<I: Iterator<Item = char>>(ch: char, chars: &mut I) -> bool {
-    if ch == CSI.0 && chars.next() == Some(CSI.1) {
-        // We have found the start of an ANSI escape code, typically
-        // used for colored terminal text. We skip until we find a
-        // "final byte" in the range 0x40–0x7E.
-        for ch in chars {
-            if ANSI_FINAL_BYTE.contains(&ch) {
-                return true;
+    if ch == CSI.0 {
+        let next = chars.next();
+        if next == Some(CSI.1) {
+            // We have found the start of an ANSI escape code, typically
+            // used for colored terminal text. We skip until we find a
+            // "final byte" in the range 0x40–0x7E.
+            for ch in chars {
+                if ANSI_FINAL_BYTE.contains(&ch) {
+                    return true;
+                }
+            }
+        } else if next == Some(']') {
+            // We have found the start of an Operating System Command, which
+            // extends until the next sequence "\x1b\\" (the String Terminator
+            // sequence) or the BEL character. The BEL character is non-standard,
+            // but it is still used quite often, for example, by GNU ls.
+            let mut last = ']';
+            for new in chars {
+                if new == '\x07' || (new == '\\' && last == CSI.0) {
+                    return true;
+                }
+                last = new;
             }
         }
     }
@@ -90,6 +105,7 @@ fn ch_width(ch: char) -> usize {
 ///
 /// assert_eq!(display_width("Café Plain"), 10);
 /// assert_eq!(display_width("\u{1b}[31mCafé Rouge\u{1b}[0m"), 10);
+/// assert_eq!(display_width("\x1b]8;;http://example.com\x1b\\This is a link\x1b]8;;\x1b\\"), 14);
 /// ```
 ///
 /// **Note:** When the `unicode-width` Cargo feature is disabled, the
@@ -404,6 +420,10 @@ mod tests {
         assert_eq!("Café Plain".len(), 11); // “é” is two bytes
         assert_eq!(display_width("Café Plain"), 10);
         assert_eq!(display_width("\u{1b}[31mCafé Rouge\u{1b}[0m"), 10);
+        assert_eq!(
+            display_width("\x1b]8;;http://example.com\x1b\\This is a link\x1b]8;;\x1b\\"),
+            14
+        );
     }
 
     #[test]