Enforce org-mode markup limit of one linebreak between delimiters

amake · amake · commit 152ade4b25ac · 2020-08-29T21:42:38.000+09:00
See amake/orgro#27
diff --git a/lib/src/grammar.dart b/lib/src/grammar.dart
@@ -184,7 +184,18 @@ class OrgContentGrammarDefinition extends GrammarDefinition {
 
   Parser code() => ref(markup, '~');
 
-  Parser markup(String marker) => drop(ref(_markup, marker), [0, -1]);
+  Parser markup(String marker) => resultPredicate(
+        drop(ref(_markup, marker), [0, -1]),
+        (result, from, to) {
+          for (var count = 0, i = from; i < to; i++) {
+            // Ensure at most one LF (U+000A) in markup span
+            if (result.codeUnitAt(i) == 0x000A && ++count > 1) {
+              return false;
+            }
+          }
+          return true;
+        },
+      );
 
   Parser _markup(String marker) =>
       (startOfInput() | was(ref(preMarkup))) &
diff --git a/test/grammar_test.dart b/test/grammar_test.dart
@@ -176,6 +176,13 @@ c/ d''');
       expect(result.value, ['~', "'", '~']);
       result = parser.parse('=+LEVEL=3+boss-TODO&#8203;="DONE"=');
       expect(result.value, ['=', '+LEVEL=3+boss-TODO&#8203;="DONE"', '=']);
+      result = parser.parse('''+foo
+bar+''');
+      expect(result.value, ['+', 'foo\nbar', '+']);
+      result = parser.parse('''+foo
+
+bar+''');
+      expect(true, result.isFailure);
     });
     test('macro reference', () {
       final parser = buildSpecific(grammarDefinition.macroReference);
diff --git a/test/parser_test.dart b/test/parser_test.dart
@@ -28,6 +28,20 @@ void main() {
       expect(link.description, 'bar');
       expect(link.location, 'foo::"[1]"');
     });
+    test('markup', () {
+      final parser = buildSpecific(parserDefinition.markups);
+      var result = parser.parse('''/foo
+bar/''');
+      final markup = result.value as OrgMarkup;
+      expect(markup.content, 'foo\nbar');
+      expect(markup.leadingDecoration, '/');
+      expect(markup.trailingDecoration, '/');
+      expect(markup.style, OrgStyle.italic);
+      result = parser.parse('''/foo
+
+bar/''');
+      expect(result.isFailure, true);
+    });
     test('macro reference', () {
       final parser = buildSpecific(parserDefinition.macroReference);
       var result = parser.parse('{{{name(arg1, arg2)}}}');
