Sourcemaps for JS

compiler/commands.nim

@@ -290,6 +290,7 @@ proc testCompileOption*(conf: ConfigRef; switch: string, info: TLineInfo): bool
   of "patterns": result = contains(conf.options, optPatterns)
   of "excessivestacktrace": result = contains(conf.globalOptions, optExcessiveStackTrace)
   of "nilseqs": result = contains(conf.options, optNilSeqs)
+  of "sourcemap": result = contains(conf.globalOptions, optSourceMap)
   else: invalidCmdLineOption(conf, passCmd1, switch, info)
 
 proc processPath(conf: ConfigRef; path: string, info: TLineInfo,
@@ -740,6 +741,8 @@ proc processSwitch*(switch, arg: string, pass: TCmdLinePass, info: TLineInfo;
     else:
       conf.cppCustomNamespace = "Nim"
     defineSymbol(conf.symbols, "cppCompileToNamespace", conf.cppCustomNamespace)
+  of "sourcemap":
+    incl(conf.globalOptions, optSourceMap)
   else:
     if strutils.find(switch, '.') >= 0: options.setConfigVar(conf, switch, arg)
     else: invalidCmdLineOption(conf, pass, switch, info)

compiler/jsgen.nim

@@ -32,7 +32,7 @@ import
   ast, astalgo, strutils, hashes, trees, platform, magicsys, extccomp, options,
   nversion, nimsets, msgs, std / sha1, bitsets, idents, types, os, tables,
   times, ropes, math, passes, ccgutils, wordrecg, renderer,
-  intsets, cgmeth, lowerings, sighashes, lineinfos, rodutils, pathutils
+  intsets, cgmeth, lowerings, sighashes, lineinfos, rodutils, pathutils, sets, sourcemap, json
 
 from modulegraphs import ModuleGraph
 
@@ -200,6 +200,8 @@ proc mapType(typ: PType): TJSTypeKind =
 proc mapType(p: PProc; typ: PType): TJSTypeKind =
   result = mapType(typ)
 
+var mangled = initSet[string]()
+
 proc mangleName(m: BModule, s: PSym): Rope =
   proc validJsName(name: string): bool =
     result = true
@@ -254,6 +256,11 @@ proc mangleName(m: BModule, s: PSym): Rope =
         add(result, rope(s.id))
     s.loc.r = result
 
+  # TODO: optimize
+  let s = $result
+  if '_' in s:
+    mangled.incl(s)
+
 proc escapeJSString(s: string): string =
   result = newStringOfCap(s.len + s.len shr 2)
   result.add("\"")
@@ -532,11 +539,17 @@ proc hasFrameInfo(p: PProc): bool =
   ({optLineTrace, optStackTrace} * p.options == {optLineTrace, optStackTrace}) and
       ((p.prc == nil) or not (sfPure in p.prc.flags))
 
+proc lineDir(config: ConfigRef, info: TLineInfo, line: int): Rope =
+  ropes.`%`("$N// line $2 $1$N",
+         [rope(toFilename(config, info)), rope(line)])
+
 proc genLineDir(p: PProc, n: PNode) =
   let line = toLinenumber(n.info)
+  if line < 0:
+    return
   if optLineDir in p.options:
-    lineF(p, "// line $2 \"$1\"$n",
-         [rope(toFilename(p.config, n.info)), rope(line)])
+    # softRnl = noRnl
+    line(p, lineDir(p.config, n.info, line))
   if {optStackTrace, optEndb} * p.options == {optStackTrace, optEndb} and
       ((p.prc == nil) or sfPure notin p.prc.flags):
     useMagic(p, "endb")
@@ -1961,6 +1974,10 @@ proc genProc(oldProc: PProc, prc: PSym): Rope =
 
   p.nested: genStmt(p, prc.getBody)
 
+
+  if optLineDir in p.config.options:
+    result = lineDir(p.config, prc.info, toLinenumber(prc.info))
+
   var def: Rope
   if not prc.constraint.isNil:
     def = (prc.constraint.strVal & " {$n$#$#$#$#$#") %
@@ -1973,7 +1990,8 @@ proc genProc(oldProc: PProc, prc: PSym): Rope =
               optionaLine(genProcBody(p, prc)),
               optionaLine(p.indentLine(returnStmt))]
   else:
-    result = ~"\L"
+    if optLineDir in p.config.options:
+      result = ~"\L"
 
     if optHotCodeReloading in p.config.options:
       # Here, we introduce thunks that create the equivalent of a jump table
@@ -2275,14 +2293,20 @@ proc myClose(graph: ModuleGraph; b: PPassContext, n: PNode): PNode =
     let ext = "js"
     let f = if globals.classes.len == 0: toFilename(m.config, FileIndex m.module.position)
             else: "nimsystem"
-    let code = wholeCode(graph, m)
+    var code = wholeCode(graph, m)
     let outfile =
       if not m.config.outFile.isEmpty:
         if m.config.outFile.string.isAbsolute: m.config.outFile
         else: AbsoluteFile(getCurrentDir() / m.config.outFile.string)
       else:
         changeFileExt(completeCFilePath(m.config, AbsoluteFile f), ext)
+    if optSourceMap in m.config.globalOptions:
+      var map: SourceMap
+      (code, map) = genSourceMap($code, mangled, f, outfile.string)
+      writeFile(outfile.string & ".map", $(%map))
+
     discard writeRopeIfNotEqual(genHeader() & code, outfile)
+
     for obj, content in items(globals.classes):
       genClass(m.config, obj, content, ext)
 

compiler/options.nim

@@ -42,6 +42,7 @@ type                          # please make sure we have under 32 options
     optLaxStrings,
     optNilSeqs
 
+
   TOptions* = set[TOption]
   TGlobalOption* = enum       # **keep binary compatible**
     gloptNone, optForceFullMake,
@@ -77,7 +78,8 @@ type                          # please make sure we have under 32 options
     optMixedMode              # true if some module triggered C++ codegen
     optListFullPaths
     optNoNimblePath
-    optDynlibOverrideAll
+    optDynlibOverrideAll,
+    optSourcemap
 
   TGlobalOptions* = set[TGlobalOption]