feat: Add support for footnotes

AI assisted: Copilot

Author: kristijanhusak

examples/queries/highlights.scm

@@ -43,6 +43,7 @@
 
 ; Like OrgProperty, easy to choose how the '[fn:LABEL] DESCRIPTION' are highlighted
 (fndef label: (expr) @OrgFootnoteLabel (description) @OrgFootnoteDescription) @OrgFootnoteDefinition
+(fnref label: (expr) @OrgFootnoteLabel) @OrgFootnoteReference
 
 ; Again like OrgProperty to change the styling of '#+' and ':'. Note that they
 ; can also be added in the query directly as anonymous nodes to style differently.

grammar.js

@@ -15,6 +15,9 @@ const org_grammar = {
     $._stars,
     $._sectionend,
     $._eof,  // Basically just '\0', but allows multiple to be matched
+    $._paragraph_continue,
+    $._fndef_continue,
+    $._fndef_stop,
     $._link_open,
     $.latex_math_single_dollar,
     $.text_dollar,
@@ -42,17 +45,18 @@ const org_grammar = {
 
     [$._tag_expr_start, $.expr],
 
-    // _multiline_text  •  ':'  …
+    // inline multiline text  •  ':'  …
     // Is the ':' continued multiline text or is it a drawer?
     [$.paragraph],
-    [$.fndef],
     // ':'  'str'  …
     // Continue the conflict from above
     [$.expr, $.drawer],
 
     // headline  'entry_token1'  ':'  •  '<'  …
     [$.entry, $.expr],
-    [$.entry, $._markup],
+    [$.entry, $._inline_markup],
+    [$.entry, $._paragraph_start_markup],
+    [$._inline_markup, $._paragraph_start_markup],
   ],
 
   rules: {
@@ -63,7 +67,24 @@ const org_grammar = {
     ),
 
     // Set up to prevent lexing conflicts of having two paragraphs in a row
-    body: $ => $._body_contents,
+    body: $ => $._top_body_contents,
+
+    _top_body_contents: $ => choice(
+      repeat1($._nl),
+      seq(repeat($._nl), $._top_multis),
+      seq(
+        repeat($._nl),
+        repeat1(seq(
+          choice(
+            seq($._top_multis, $._nl),
+            seq($.fndef, $.fndef),
+            seq(optional(choice(alias($._top_paragraph, $.paragraph), $.fndef)), $._element),
+          ),
+          repeat($._nl),
+        )),
+        optional($._top_multis)
+      ),
+    ),
 
     _body_contents: $ => choice(
       repeat1($._nl),
@@ -73,6 +94,7 @@ const org_grammar = {
         repeat1(seq(
           choice(
             seq($._multis, $._nl),
+            seq($.fndef, $.fndef),
             seq(optional(choice($.paragraph, $.fndef)), $._element),
           ),
           repeat($._nl),
@@ -81,6 +103,12 @@ const org_grammar = {
       ),
     ),
 
+    _top_multis: $ => choice(
+      alias($._top_paragraph, $.paragraph),
+      $._directive_list,
+      $.fndef,
+    ),
+
     link: $ => seq(
       alias($._link_open, '[['),
       field('url', repeat(alias($._expr_with_space, $.expr))),
@@ -172,9 +200,9 @@ const org_grammar = {
     ),
 
     item: $ => choice(
-      seq($.expr, field('priority', $.priority), repeat1($._markup)),
-      seq(field('priority', $.priority), repeat($._markup)),
-      repeat1($._markup)
+      seq($.expr, field('priority', $.priority), repeat1($._inline_markup)),
+      seq(field('priority', $.priority), repeat($._inline_markup)),
+      repeat1($._inline_markup)
     ),
 
     tag_list: $ => prec.dynamic(1, seq(
@@ -240,17 +268,24 @@ const org_grammar = {
       alias(prec(-1, /[^\[<\]>\p{Z}\t\n\r]+/), $.expr),
     ),
 
-    paragraph: $ => seq(optional($._directive_list), $._multiline_text),
+    paragraph: $ => seq(optional($._directive_list), $._inline_multiline_text),
+    _top_paragraph: $ => seq(optional($._directive_list), $._top_paragraph_text),
 
-    fndef: $ => seq(
+    fndef: $ => prec.dynamic(10, prec.right(1, seq(
       optional($._directive_list),
       seq(
         alias(/\[fn:/i, '[fn:'),
         field('label', alias(/[^\p{Z}\t\n\r\]]+/, $.expr)),
         ']',
       ),
-      field('description', alias($._multiline_text, $.description))
-    ),
+      optional(field('description', alias($._fndef_multiline_text, $.description)))
+    ))),
+
+    fnref: $ => prec(-1, seq(
+      alias(/\[fn:/i, '[fn:'),
+      field('label', alias(/[^\p{Z}\t\n\r\]]+/, $.expr)),
+      ']',
+    )),
 
     _directive_list: $ => repeat1(field('directive', $.directive)),
     directive: $ => seq(
@@ -393,13 +428,54 @@ const org_grammar = {
     _nl: _ => choice('\n', '\r'),
     _eol: $ => choice('\n', '\r', $._eof),
 
-    _expr_line: $ => repeat1($._markup),
-    _multiline_text: $ => repeat1(seq(
-      repeat1($._markup),
-      $._eol
+    _expr_line: $ => repeat1($._inline_markup),
+    _inline_multiline_text: $ => repeat1(seq(
+      repeat1($._inline_markup),
+      $._eol,
     )),
+    _top_paragraph_text: $ => prec.right(seq(
+      repeat1($._paragraph_start_markup),
+      repeat($._inline_markup),
+      repeat(seq(
+        $._paragraph_continue,
+        repeat1($._inline_markup),
+      )),
+      $._eol,
+    )),
+
+    _fndef_multiline_text: $ => seq(
+      repeat1($._fndef_markup),
+      repeat(seq(
+        $._fndef_continue,
+        repeat1($._fndef_markup),
+      )),
+      choice($._fndef_stop, $._eof),
+    ),
+
+    _inline_markup: $ => choice(
+      $.expr,
+      $.inline_code_block,
+      $.inline_math_block,
+      $.display_math_block,
+      $.link,
+      $.link_desc,
+      $.fnref,
+      $.timestamp,
+      $.citation,
+    ),
+
+    _paragraph_start_markup: $ => choice(
+      $.expr,
+      $.inline_code_block,
+      $.inline_math_block,
+      $.display_math_block,
+      $.link,
+      $.link_desc,
+      $.timestamp,
+      $.citation,
+    ),
 
-    _markup: $ => choice(
+    _fndef_markup: $ => choice(
       $.expr,
       $.inline_code_block,
       $.inline_math_block,