rst indentation fixes (ref #17340) (#17715)

2 files changed, 74 insertions, 39 deletions

diff --git a/lib/packages/docutils/rst.nim b/lib/packages/docutils/rst.nim
index c2385d517..7c4b92f88 100644
--- a/lib/packages/docutils/rst.nim
+++ b/lib/packages/docutils/rst.nim
@@ -1532,6 +1532,55 @@ proc parseUntilNewline(p: var RstParser, father: PRstNode) =
     of tkEof, tkIndent: break
 
 proc parseSection(p: var RstParser, result: PRstNode) {.gcsafe.}
+
+proc tokenAfterNewline(p: RstParser, start: int): int =
+  result = start
+  while true:
+    case p.tok[result].kind
+    of tkEof:
+      break
+    of tkIndent:
+      inc result
+      break
+    else: inc result
+
+proc tokenAfterNewline(p: RstParser): int {.inline.} =
+  result = tokenAfterNewline(p, p.idx)
+
+proc getWrappableIndent(p: RstParser): int =
+  ## Gets baseline indentation for bodies of field lists and directives.
+  ## Handles situations like this (with possible de-indent in [case.3])::
+  ##
+  ##   :field:   definition                                          [case.1]
+  ##
+  ##   currInd   currentTok(p).col
+  ##   |         |
+  ##   v         v
+  ##
+  ##   .. Note:: defItem:                                            [case.2]
+  ##                 definition
+  ##
+  ##                 ^
+  ##                 |
+  ##                 nextIndent
+  ##
+  ##   .. Note:: - point1                                            [case.3]
+  ##       - point 2
+  ##
+  ##       ^
+  ##       |
+  ##       nextIndent
+  if currentTok(p).kind == tkIndent:
+    result = currentTok(p).ival
+  else:
+    var nextIndent = p.tok[tokenAfterNewline(p)-1].ival
+    if nextIndent <= currInd(p):          # parse only this line     [case.1]
+      result = currentTok(p).col
+    elif nextIndent >= currentTok(p).col: # may be a definition list [case.2]
+      result = currentTok(p).col
+    else:
+      result = nextIndent                 #                          [case.3]
+
 proc parseField(p: var RstParser): PRstNode =
   ## Returns a parsed rnField node.
   ##
@@ -1541,13 +1590,12 @@ proc parseField(p: var RstParser): PRstNode =
   var fieldname = newRstNode(rnFieldName)
   parseUntil(p, fieldname, ":", false)
   var fieldbody = newRstNode(rnFieldBody)
-  if currentTok(p).kind != tkIndent: parseLine(p, fieldbody)
-  if currentTok(p).kind == tkIndent:
-    var indent = currentTok(p).ival
-    if indent > col:
-      pushInd(p, indent)
-      parseSection(p, fieldbody)
-      popInd(p)
+  if currentTok(p).kind == tkWhite: inc p.idx
+  let indent = getWrappableIndent(p)
+  if indent > col:
+    pushInd(p, indent)
+    parseSection(p, fieldbody)
+    popInd(p)
   result.add(fieldname)
   result.add(fieldbody)
 
@@ -1652,20 +1700,6 @@ proc countTitles(p: var RstParser, n: PRstNode) =
         if p.s.hTitleCnt >= 2:
           break
 
-proc tokenAfterNewline(p: RstParser, start: int): int =
-  result = start
-  while true:
-    case p.tok[result].kind
-    of tkEof:
-      break
-    of tkIndent:
-      inc result
-      break
-    else: inc result
-
-proc tokenAfterNewline(p: RstParser): int {.inline.} =
-  result = tokenAfterNewline(p, p.idx)
-
 proc isAdornmentHeadline(p: RstParser, adornmentIdx: int): bool =
   ## check that underline/overline length is enough for the heading.
   ## No support for Unicode.
@@ -1752,7 +1786,7 @@ proc whichSection(p: RstParser): RstNodeKind =
       return rnCodeBlock
     elif currentTok(p).symbol == "::":
       return rnLiteralBlock
-    elif currentTok(p).symbol == ".."  and predNL(p) and
+    elif currentTok(p).symbol == ".."  and
        nextTok(p).kind in {tkWhite, tkIndent}:
      return rnDirective
   case currentTok(p).kind
@@ -1780,10 +1814,9 @@ proc whichSection(p: RstParser): RstNodeKind =
     elif match(p, tokenAfterNewline(p), "aI") and
         isAdornmentHeadline(p, tokenAfterNewline(p)):
       result = rnHeadline
-    elif predNL(p) and
-        currentTok(p).symbol in ["+", "*", "-"] and nextTok(p).kind == tkWhite:
+    elif currentTok(p).symbol in ["+", "*", "-"] and nextTok(p).kind == tkWhite:
       result = rnBulletList
-    elif match(p, p.idx, ":w:E") and predNL(p):
+    elif match(p, p.idx, ":w:E"):
       # (currentTok(p).symbol == ":")
       result = rnFieldList
     elif match(p, p.idx, "(e) ") or match(p, p.idx, "e) ") or
@@ -2350,9 +2383,11 @@ proc parseDirective(p: var RstParser, k: RstNodeKind, flags: DirFlags): PRstNode
       parseLine(p, args)
   result.add(args)
   if hasOptions in flags:
-    if currentTok(p).kind == tkIndent and currentTok(p).ival >= 3 and
+    if currentTok(p).kind == tkIndent and currentTok(p).ival > currInd(p) and
         nextTok(p).symbol == ":":
+      pushInd(p, currentTok(p).ival)
       options = parseFields(p)
+      popInd(p)
   result.add(options)
 
 proc indFollows(p: RstParser): bool =
@@ -2363,11 +2398,9 @@ proc parseBlockContent(p: var RstParser, father: var PRstNode,
   ## parse the final content part of explicit markup blocks (directives,
   ## footnotes, etc). Returns true if succeeded.
   if currentTok(p).kind != tkIndent or indFollows(p):
-    var nextIndent = p.tok[tokenAfterNewline(p)-1].ival
-    if nextIndent <= currInd(p):  # parse only this line
-      nextIndent = currentTok(p).col
-    pushInd(p, nextIndent)
-    var content = contentParser(p)
+    let blockIndent = getWrappableIndent(p)
+    pushInd(p, blockIndent)
+    let content = contentParser(p)
     popInd(p)
     father.add content
     result = true
diff --git a/lib/packages/docutils/rstast.nim b/lib/packages/docutils/rstast.nim
index 394cc2698..00f3f2b35 100644
--- a/lib/packages/docutils/rstast.nim
+++ b/lib/packages/docutils/rstast.nim
@@ -350,7 +350,7 @@ proc renderRstToJson*(node: PRstNode): string =
 proc renderRstToStr*(node: PRstNode, indent=0): string =
   ## Writes the parsed RST `node` into a compact string
   ## representation in the format (one line per every sub-node):
-  ## ``indent - kind - text - level - order - anchor (if non-zero)``
+  ## ``indent - kind - [text|level|order|adType] - anchor (if non-zero)``
   ## (suitable for debugging of RST parsing).
   if node == nil:
     result.add " ".repeat(indent) & "[nil]\n"
@@ -358,21 +358,23 @@ proc renderRstToStr*(node: PRstNode, indent=0): string =
   result.add " ".repeat(indent) & $node.kind
   case node.kind
   of rnLeaf, rnSmiley:
-    result.add (if node.text == "": "" else: "\t'" & node.text & "'")
+    result.add (if node.text == "": "" else: "  '" & node.text & "'")
   of rnEnumList:
-    result.add "\tlabelFmt=" & node.labelFmt
+    result.add "  labelFmt=" & node.labelFmt
   of rnLineBlockItem:
     var txt: string
-    if node.lineIndent == "\n": txt = "\t(blank line)"
-    else: txt = "\tlineIndent=" & $node.lineIndent.len
+    if node.lineIndent == "\n": txt = "  (blank line)"
+    else: txt = "  lineIndent=" & $node.lineIndent.len
     result.add txt
+  of rnAdmonition:
+    result.add "  adType=" & node.adType
   of rnHeadline, rnOverline, rnMarkdownHeadline:
-    result.add "\tlevel=" & $node.level
+    result.add "  level=" & $node.level
   of rnFootnote, rnCitation, rnFootnoteRef, rnOptionListItem:
-    result.add (if node.order == 0:   "" else: "\torder=" & $node.order)
+    result.add (if node.order == 0:   "" else: "  order=" & $node.order)
   else:
     discard
-  result.add (if node.anchor == "": "" else: "\tanchor='" & node.anchor & "'")
+  result.add (if node.anchor == "": "" else: "  anchor='" & node.anchor & "'")
   result.add "\n"
   for son in node.sons:
     result.add renderRstToStr(son, indent=indent+2)