Merge branch 'devel' into typedesc-reforms

1 files changed, 115 insertions, 49 deletions

diff --git a/compiler/layouter.nim b/compiler/layouter.nim
index 90e9d6fd7..36ad08696 100644
--- a/compiler/layouter.nim
+++ b/compiler/layouter.nim
@@ -7,11 +7,7 @@
 #    distribution, for details about the copyright.
 #
 
-## Layouter for nimpretty. Still primitive but useful.
-## TODO
-## - Fix 'echo ()' vs 'echo()' difference!
-## - Make indentations consistent.
-## - Align 'if' and 'case' expressions properly.
+## Layouter for nimpretty.
 
 import idents, lexer, lineinfos, llstream, options, msgs, strutils
 from os import changeFileExt
@@ -24,32 +20,44 @@ type
   SplitKind = enum
     splitComma, splitParLe, splitAnd, splitOr, splitIn, splitBinary
 
+  SemicolonKind = enum
+    detectSemicolonKind, useSemicolon, dontTouch
+
   Emitter* = object
-    f: PLLStream
     config: ConfigRef
     fid: FileIndex
     lastTok: TTokType
     inquote: bool
-    col, lastLineNumber, lineSpan, indentLevel: int
+    semicolons: SemicolonKind
+    col, lastLineNumber, lineSpan, indentLevel, indWidth: int
+    nested: int
+    doIndentMore*: int
     content: string
+    indentStack: seq[int]
     fixedUntil: int # marks where we must not go in the content
     altSplitPos: array[SplitKind, int] # alternative split positions
 
-proc openEmitter*(em: var Emitter, config: ConfigRef, fileIdx: FileIndex) =
-  let outfile = changeFileExt(config.toFullPath(fileIdx), ".pretty.nim")
-  em.f = llStreamOpen(outfile, fmWrite)
+proc openEmitter*(em: var Emitter, cache: IdentCache;
+                  config: ConfigRef, fileIdx: FileIndex) =
+  let fullPath = config.toFullPath(fileIdx)
+  em.indWidth = getIndentWidth(fileIdx, llStreamOpen(fullPath, fmRead),
+                               cache, config)
+  if em.indWidth == 0: em.indWidth = 2
   em.config = config
   em.fid = fileIdx
   em.lastTok = tkInvalid
   em.inquote = false
   em.col = 0
   em.content = newStringOfCap(16_000)
-  if em.f == nil:
-    rawMessage(config, errGenerated, "cannot open file: " & outfile)
+  em.indentStack = newSeqOfCap[int](30)
+  em.indentStack.add 0
 
 proc closeEmitter*(em: var Emitter) =
-  em.f.llStreamWrite em.content
-  llStreamClose(em.f)
+  var f = llStreamOpen(em.config.outFile, fmWrite)
+  if f == nil:
+    rawMessage(em.config, errGenerated, "cannot open file: " & em.config.outFile)
+  f.llStreamWrite em.content
+  llStreamClose(f)
 
 proc countNewlines(s: string): int =
   result = 0
@@ -69,28 +77,41 @@ template wr(x) =
 
 template goodCol(col): bool = col in 40..MaxLineLen
 
-const splitters = {tkComma, tkSemicolon, tkParLe, tkParDotLe,
-                   tkBracketLe, tkBracketLeColon, tkCurlyDotLe,
-                   tkCurlyLe}
+const
+  openPars = {tkParLe, tkParDotLe,
+              tkBracketLe, tkBracketLeColon, tkCurlyDotLe,
+              tkCurlyLe}
+  splitters = openPars + {tkComma, tkSemicolon}
+  oprSet = {tkOpr, tkDiv, tkMod, tkShl, tkShr, tkIn, tkNotin, tkIs,
+            tkIsnot, tkNot, tkOf, tkAs, tkDotDot, tkAnd, tkOr, tkXor}
 
 template rememberSplit(kind) =
   if goodCol(em.col):
     em.altSplitPos[kind] = em.content.len
 
+template moreIndent(em): int =
+  (if em.doIndentMore > 0: em.indWidth*2 else: em.indWidth)
+
 proc softLinebreak(em: var Emitter, lit: string) =
   # XXX Use an algorithm that is outlined here:
   # https://llvm.org/devmtg/2013-04/jasper-slides.pdf
   # +2 because we blindly assume a comma or ' &' might follow
   if not em.inquote and em.col+lit.len+2 >= MaxLineLen:
     if em.lastTok in splitters:
+      while em.content.len > 0 and em.content[em.content.high] == ' ':
+        setLen(em.content, em.content.len-1)
       wr("\L")
       em.col = 0
-      for i in 1..em.indentLevel+2: wr(" ")
+      for i in 1..em.indentLevel+moreIndent(em): wr(" ")
     else:
       # search backwards for a good split position:
       for a in em.altSplitPos:
         if a > em.fixedUntil:
-          let ws = "\L" & repeat(' ',em.indentLevel+2)
+          var spaces = 0
+          while a+spaces < em.content.len and em.content[a+spaces] == ' ':
+            inc spaces
+          if spaces > 0: delete(em.content, a, a+spaces-1)
+          let ws = "\L" & repeat(' ',em.indentLevel+moreIndent(em))
           em.col = em.content.len - a
           em.content.insert(ws, a)
           break
@@ -98,7 +119,7 @@ proc softLinebreak(em: var Emitter, lit: string) =
 proc emitTok*(em: var Emitter; L: TLexer; tok: TToken) =
 
   template endsInWhite(em): bool =
-    em.content.len > 0 and em.content[em.content.high] in {' ', '\L'}
+    em.content.len == 0 or em.content[em.content.high] in {' ', '\L'}
   template endsInAlpha(em): bool =
     em.content.len > 0 and em.content[em.content.high] in SymChars+{'_'}
 
@@ -120,14 +141,32 @@ proc emitTok*(em: var Emitter; L: TLexer; tok: TToken) =
     em.fixedUntil = em.content.high
 
   elif tok.indent >= 0:
-    em.indentLevel = tok.indent
+    if em.lastTok in (splitters + oprSet):
+      em.indentLevel = tok.indent
+    else:
+      if tok.indent > em.indentStack[^1]:
+        em.indentStack.add tok.indent
+      else:
+        # dedent?
+        while em.indentStack.len > 1 and em.indentStack[^1] > tok.indent:
+          discard em.indentStack.pop()
+      em.indentLevel = em.indentStack.high * em.indWidth
+    #[ we only correct the indentation if it is not in an expression context,
+       so that code like
+
+        const splitters = {tkComma, tkSemicolon, tkParLe, tkParDotLe,
+                          tkBracketLe, tkBracketLeColon, tkCurlyDotLe,
+                          tkCurlyLe}
+
+       is not touched.
+    ]#
     # remove trailing whitespace:
     while em.content.len > 0 and em.content[em.content.high] == ' ':
       setLen(em.content, em.content.len-1)
     wr("\L")
     for i in 2..tok.line - em.lastLineNumber: wr("\L")
     em.col = 0
-    for i in 1..tok.indent:
+    for i in 1..em.indentLevel:
       wr(" ")
     em.fixedUntil = em.content.high
 
@@ -135,49 +174,64 @@ proc emitTok*(em: var Emitter; L: TLexer; tok: TToken) =
   of tokKeywordLow..tokKeywordHigh:
     if endsInAlpha(em):
       wr(" ")
-    elif not em.inquote and not endsInWhite(em):
+    elif not em.inquote and not endsInWhite(em) and
+        em.lastTok notin openPars:
+      #and tok.tokType in oprSet
       wr(" ")
 
-    wr(TokTypeToStr[tok.tokType])
+    if not em.inquote:
+      wr(TokTypeToStr[tok.tokType])
 
-    case tok.tokType
-    of tkAnd: rememberSplit(splitAnd)
-    of tkOr: rememberSplit(splitOr)
-    of tkIn, tkNotin:
-      rememberSplit(splitIn)
-      wr(" ")
-    else: discard
+      case tok.tokType
+      of tkAnd: rememberSplit(splitAnd)
+      of tkOr: rememberSplit(splitOr)
+      of tkIn, tkNotin:
+        rememberSplit(splitIn)
+        wr(" ")
+      else: discard
+    else:
+      # keywords in backticks are not normalized:
+      wr(tok.ident.s)
 
   of tkColon:
     wr(TokTypeToStr[tok.tokType])
     wr(" ")
   of tkSemicolon, tkComma:
     wr(TokTypeToStr[tok.tokType])
-    wr(" ")
     rememberSplit(splitComma)
-  of tkParLe, tkParRi, tkBracketLe,
-     tkBracketRi, tkCurlyLe, tkCurlyRi,
-     tkBracketDotLe, tkBracketDotRi,
-     tkCurlyDotLe, tkCurlyDotRi,
-     tkParDotLe, tkParDotRi,
-     tkColonColon, tkDot, tkBracketLeColon:
+    wr(" ")
+  of tkParDotLe, tkParLe, tkBracketDotLe, tkBracketLe,
+     tkCurlyLe, tkCurlyDotLe, tkBracketLeColon:
+    if tok.strongSpaceA > 0 and not em.endsInWhite:
+      wr(" ")
+    wr(TokTypeToStr[tok.tokType])
+    rememberSplit(splitParLe)
+  of tkParRi,
+     tkBracketRi, tkCurlyRi,
+     tkBracketDotRi,
+     tkCurlyDotRi,
+     tkParDotRi,
+     tkColonColon, tkDot:
     wr(TokTypeToStr[tok.tokType])
-    if tok.tokType in splitters:
-      rememberSplit(splitParLe)
   of tkEquals:
-    if not em.endsInWhite: wr(" ")
+    if not em.inquote and not em.endsInWhite: wr(" ")
     wr(TokTypeToStr[tok.tokType])
-    wr(" ")
+    if not em.inquote: wr(" ")
   of tkOpr, tkDotDot:
-    if not em.endsInWhite: wr(" ")
-    wr(tok.ident.s)
-    template isUnary(tok): bool =
-      tok.strongSpaceB == 0 and tok.strongSpaceA > 0
+    if tok.strongSpaceA == 0 and tok.strongSpaceB == 0:
+      # if not surrounded by whitespace, don't produce any whitespace either:
+      wr(tok.ident.s)
+    else:
+      if not em.endsInWhite: wr(" ")
+      wr(tok.ident.s)
+      template isUnary(tok): bool =
+        tok.strongSpaceB == 0 and tok.strongSpaceA > 0
 
-    if not isUnary(tok) or em.lastTok in {tkOpr, tkDotDot}:
-      wr(" ")
-      rememberSplit(splitBinary)
+      if not isUnary(tok):
+        wr(" ")
+        rememberSplit(splitBinary)
   of tkAccent:
+    if not em.inquote and endsInAlpha(em): wr(" ")
     wr(TokTypeToStr[tok.tokType])
     em.inquote = not em.inquote
   of tkComment:
@@ -206,3 +260,15 @@ proc starWasExportMarker*(em: var Emitter) =
     setLen(em.content, em.content.len-3)
     em.content.add("*")
     dec em.col, 2
+
+proc commaWasSemicolon*(em: var Emitter) =
+  if em.semicolons == detectSemicolonKind:
+    em.semicolons = if em.content.endsWith(", "): dontTouch else: useSemicolon
+  if em.semicolons == useSemicolon and em.content.endsWith(", "):
+    setLen(em.content, em.content.len-2)
+    em.content.add("; ")
+
+proc curlyRiWasPragma*(em: var Emitter) =
+  if em.content.endsWith("}"):
+    setLen(em.content, em.content.len-1)
+    em.content.add(".}")