18. Restore list indent behavior

crates/typst-syntax/src/lexer.rs

@@ -69,9 +69,11 @@ impl<'s> Lexer<'s> {
         self.newline
     }
 
-    /// The number of characters until the most recent newline.
+    /// The number of characters until the most recent newline from an index.
-    pub fn column(&self) -> usize {
+    pub fn column(&self, index: usize) -> usize {
-        self.s.before().chars().rev().take_while(|&c| !is_newline(c)).count()
+        let mut s = self.s; // Make a new temporary scanner (cheap).
+        s.jump(index);
+        s.before().chars().rev().take_while(|&c| !is_newline(c)).count()
     }
 }
 

crates/typst-syntax/src/parser.rs

@@ -1545,11 +1545,7 @@ struct Token {
 /// Information about a newline if present (currently only relevant in Markup).
 #[derive(Debug, Clone, Copy)]
 struct Newline {
-    /// The column of our token in its line.
+    /// The column of the start of our token in its line.
-    ///
-    /// Note that this is actually the column of the first non-whitespace
-    /// `SyntaxKind` in the line, so `\n  /**/- list` has column 2 (not 6)
-    /// because the block comment is the first non-space kind.
     column: Option<usize>,
     /// Whether any of our newlines were paragraph breaks.
     parbreak: bool,
@@ -1684,10 +1680,6 @@ impl<'s> Parser<'s> {
 
     /// The number of characters until the most recent newline from the current
     /// token, or 0 if it did not follow a newline.
-    ///
-    /// Note that this is actually the column of the first non-whitespace
-    /// `SyntaxKind` in the line, so `\n  /**/- list` has column 2 (not 6)
-    /// because the block comment is the first non-space kind.
     fn current_column(&self) -> usize {
         self.token.newline.and_then(|newline| newline.column).unwrap_or(0)
     }
@@ -1852,29 +1844,30 @@ impl<'s> Parser<'s> {
         let (mut kind, mut node) = lexer.next();
         let mut n_trivia = 0;
         let mut had_newline = false;
-        let mut newline = Newline { column: None, parbreak: false };
+        let mut parbreak = false;
 
         while kind.is_trivia() {
-            if lexer.newline() {
+            had_newline |= lexer.newline(); // Newlines are always trivia.
-                // Newlines are always trivia.
+            parbreak |= kind == SyntaxKind::Parbreak;
-                had_newline = true;
-                newline.parbreak |= kind == SyntaxKind::Parbreak;
-                if lexer.mode() == LexMode::Markup {
-                    newline.column = Some(lexer.column());
-                }
-            }
             n_trivia += 1;
             nodes.push(node);
             start = lexer.cursor();
             (kind, node) = lexer.next();
         }
-        if had_newline && nl_mode.stop_at(newline, kind) {
-            // Insert a temporary `SyntaxKind::End` to halt the parser.
-            // The actual kind will be restored from `node` later.
-            kind = SyntaxKind::End;
-        }
 
-        let newline = had_newline.then_some(newline);
+        let newline = if had_newline {
+            let column = (lexer.mode() == LexMode::Markup).then(|| lexer.column(start));
+            let newline = Newline { column, parbreak };
+            if nl_mode.stop_at(newline, kind) {
+                // Insert a temporary `SyntaxKind::End` to halt the parser.
+                // The actual kind will be restored from `node` later.
+                kind = SyntaxKind::End;
+            }
+            Some(newline)
+        } else {
+            None
+        };
+
         Token { kind, node, n_trivia, newline, start, prev_end }
     }
 }

tests/suite/model/list.typ

@@ -34,6 +34,51 @@ _Shopping list_
    - C
 - D
 
+--- list-indent-trivia-nesting ---
+// Test indent nesting behavior with odd trivia (comments and spaces).
+
+#let indented = [
+- a
+ /**/- b
+/**/ - c
+   /*spanning
+     multiple
+      lines */ - d
+    - e
+/**/       - f
+/**/  - g
+]
+// Current behavior is that list columns are based on the first non-whitespace
+// element in their line, so the block comments here determine the column the
+// list starts at
+
+#let item = list.item
+#let manual = {
+  [ ]
+  item({
+    [a]
+    [ ]
+    item[b]
+    [ ]; [ ]
+    item({
+      [c]
+      [ ]; [ ]
+      item[d]
+    })
+    [ ]
+    item({
+      [e]
+      [ ]; [ ]
+      item[f]
+      [ ]; [ ]
+      item[g]
+    })
+  })
+  [ ]
+}
+
+#test(indented, manual)
+
 --- list-tabs ---
 // This works because tabs are used consistently.
 	- A with 1 tab