rst: allow comment to continue on second line (#18338)

lib/packages/docutils/rst.nim

@@ -1615,24 +1615,16 @@ proc getDirective(p: var RstParser): string =
             "too many colons for a directive (should be ::)",
             p.tok[afterIdx].line, p.tok[afterIdx].col)
 
-proc parseComment(p: var RstParser): PRstNode =
-  case currentTok(p).kind
-  of tkIndent, tkEof:
-    if currentTok(p).kind != tkEof and nextTok(p).kind == tkIndent:
-      inc p.idx              # empty comment
-    else:
-      var indent = currentTok(p).ival
-      while true:
-        case currentTok(p).kind
-        of tkEof:
-          break
-        of tkIndent:
-          if currentTok(p).ival < indent: break
-        else:
-          discard
-        inc p.idx
+proc parseComment(p: var RstParser, col: int): PRstNode =
+  if currentTok(p).kind != tkEof and nextTok(p).kind == tkIndent:
+    inc p.idx              # empty comment
   else:
-    while currentTok(p).kind notin {tkIndent, tkEof}: inc p.idx
+    while currentTok(p).kind != tkEof:
+      if currentTok(p).kind == tkIndent and currentTok(p).ival > col or
+         currentTok(p).kind != tkIndent and currentTok(p).col > col:
+        inc p.idx
+      else:
+        break
   result = nil
 
 proc parseLine(p: var RstParser, father: PRstNode) =
@@ -2841,7 +2833,7 @@ proc parseDotDot(p: var RstParser): PRstNode =
       (n = parseFootnote(p); n != nil):
     result = n
   else:
-    result = parseComment(p)
+    result = parseComment(p, col)
 
 proc rstParsePass1*(fragment, filename: string,
                     line, column: int,

tests/stdlib/trst.nim

@@ -83,6 +83,72 @@ suite "RST parsing":
               rnLeaf  'set'
         """)
 
+  test "RST comment":
+    check(dedent"""
+        .. comment1
+         comment2
+        someParagraph""".toAst ==
+      dedent"""
+        rnLeaf  'someParagraph'
+        """)
+
+    check(dedent"""
+        ..
+         comment1
+         comment2
+        someParagraph""".toAst ==
+      dedent"""
+        rnLeaf  'someParagraph'
+        """)
+
+  test "check that additional line right after .. ends comment":
+    check(dedent"""
+        ..
+
+         notAcomment1
+         notAcomment2
+        someParagraph""".toAst ==
+      dedent"""
+        rnInner
+          rnBlockQuote
+            rnInner
+              rnLeaf  'notAcomment1'
+              rnLeaf  ' '
+              rnLeaf  'notAcomment2'
+          rnParagraph
+            rnLeaf  'someParagraph'
+        """)
+
+  test "but blank lines after 2nd non-empty line don't end the comment":
+    check(dedent"""
+        ..
+           comment1
+
+
+         comment2
+        someParagraph""".toAst ==
+      dedent"""
+        rnLeaf  'someParagraph'
+        """)
+
+  test "using .. as separator b/w directives and block quotes":
+    check(dedent"""
+        .. note:: someNote
+    
+        ..
+    
+          someBlockQuote""".toAst ==
+      dedent"""
+        rnInner
+          rnAdmonition  adType=note
+            [nil]
+            [nil]
+            rnLeaf  'someNote'
+          rnBlockQuote
+            rnInner
+              rnLeaf  'someBlockQuote'
+        """)
+
 suite "RST indentation":
   test "nested bullet lists":
     let input = dedent """