fix(chat): Fix display of square brackets in chat output (#971)

* fix(cli): Fix display of square brackets in chat output

Modify URL parser to properly handle square brackets in text by saving
the input position and resetting it when the complete URL pattern does
not match. This ensures square brackets are correctly displayed in chat
output when they are not part of a markdown link.

* fix fmt, improve test coverage

* add testcase

* change testcase name

* fix format

Author: ymhiroki

crates/q_cli/src/cli/chat/parse.rs

@@ -404,9 +404,30 @@ fn url<'a, 'b>(
     state: &'b mut ParseState,
 ) -> impl FnMut(&mut Partial<&'a str>) -> PResult<(), Error<'a>> + 'b {
     move |i| {
-        let display = delimited("[", take_until(1.., "]("), "]").parse_next(i)?;
-        let link = delimited("(", take_till(0.., ')'), ")").parse_next(i)?;
+        // Save the current input position
+        let start = i.checkpoint();
+
+        // Try to match the first part of URL pattern "[text]"
+        let display = match delimited::<_, _, _, _, Error<'a>, _, _, _>("[", take_until(1.., "]("), "]").parse_next(i) {
+            Ok(display) => display,
+            Err(_) => {
+                // If it doesn't match, reset position and fail
+                i.reset(&start);
+                return Err(ErrMode::from_error_kind(i, ErrorKind::Fail));
+            },
+        };
+
+        // Try to match the second part of URL pattern "(url)"
+        let link = match delimited::<_, _, _, _, Error<'a>, _, _, _>("(", take_till(0.., ')'), ")").parse_next(i) {
+            Ok(link) => link,
+            Err(_) => {
+                // If it doesn't match, reset position and fail
+                i.reset(&start);
+                return Err(ErrMode::from_error_kind(i, ErrorKind::Fail));
+            },
+        };
 
+        // Only generate output if the complete URL pattern matches
         queue_newline_or_advance(&mut o, state, display.width() + 1)?;
         queue(&mut o, style::SetForegroundColor(URL_TEXT_COLOR))?;
         queue(&mut o, style::Print(format!("{display} ")))?;
@@ -726,4 +747,16 @@ mod tests {
         style::SetForegroundColor(BLOCKQUOTE_COLOR),
         style::Print("│ hello"),
     ]);
+    validate!(square_bracket_1, "[test]", [style::Print("[test]")]);
+    validate!(square_bracket_2, "Text with [brackets]", [style::Print(
+        "Text with [brackets]"
+    )]);
+    validate!(square_bracket_empty, "[]", [style::Print("[]")]);
+    validate!(square_bracket_array, "a[i]", [style::Print("a[i]")]);
+    validate!(square_bracket_url_like_1, "[text] without url part", [style::Print(
+        "[text] without url part"
+    )]);
+    validate!(square_bracket_url_like_2, "[text](without url part", [style::Print(
+        "[text](without url part"
+    )]);
 }