fix js stacktraces, unify all file,line,col formatting into a single function (#14230)

* fix https://github.com/timotheecour/Nim/issues/135 ; unify all file,line,col formatting into a single function

lib/system/assertions.nim

@@ -1,17 +1,17 @@
 when not declared(sysFatal):
   include "system/fatal"
 
+import std/private/miscdollars
 # ---------------------------------------------------------------------------
 # helpers
 
 type InstantiationInfo = tuple[filename: string, line: int, column: int]
 
 proc `$`(x: int): string {.magic: "IntToStr", noSideEffect.}
-
 proc `$`(info: InstantiationInfo): string =
   # The +1 is needed here
   # instead of overriding `$` (and changing its meaning), consider explicit name.
-  info.filename & "(" & $info.line & ", " & $(info.column+1) & ")"
+  result.toLocation(info.filename, info.line, info.column+1)
 
 # ---------------------------------------------------------------------------
 

lib/system/excpt.nim

@@ -10,6 +10,8 @@
 # Exception handling code. Carefully coded so that tiny programs which do not
 # use the heap (and nor exceptions) do not include the GC or memory allocator.
 
+import std/private/miscdollars
+
 var
   errorMessageWriter*: (proc(msg: string) {.tags: [WriteIOEffect], benign,
                                             nimcall.})
@@ -240,11 +242,7 @@ proc auxWriteStackTrace(f: PFrame; s: var seq[StackTraceEntry]) =
 
 template addFrameEntry(s: var string, f: StackTraceEntry|PFrame) =
   var oldLen = s.len
-  add(s, f.filename)
-  if f.line > 0:
-    add(s, '(')
-    add(s, $f.line)
-    add(s, ')')
+  s.toLocation(f.filename, f.line, 0)
   for k in 1..max(1, 25-(s.len-oldLen)): add(s, ' ')
   add(s, f.procname)
   when NimStackTraceMsgs:

lib/system/jssys.nim

@@ -8,6 +8,7 @@
 #
 
 include system/indexerrors
+import std/private/miscdollars
 
 proc log*(s: cstring) {.importc: "console.log", varargs, nodecl.}
 
@@ -70,7 +71,7 @@ proc getCurrentExceptionMsg*(): string =
 
 proc auxWriteStackTrace(f: PCallFrame): string =
   type
-    TempFrame = tuple[procname: cstring, line: int]
+    TempFrame = tuple[procname: cstring, line: int, filename: cstring]
   var
     it = f
     i = 0
@@ -79,6 +80,7 @@ proc auxWriteStackTrace(f: PCallFrame): string =
   while it != nil and i <= high(tempFrames):
     tempFrames[i].procname = it.procname
     tempFrames[i].line = it.line
+    tempFrames[i].filename = it.filename
     inc(i)
     inc(total)
     it = it.prev
@@ -92,10 +94,9 @@ proc auxWriteStackTrace(f: PCallFrame): string =
     add(result, $(total-i))
     add(result, " calls omitted) ...\n")
   for j in countdown(i-1, 0):
+    result.toLocation($tempFrames[j].filename, tempFrames[j].line, 0)
+    add(result, " at ")
     add(result, tempFrames[j].procname)
-    if tempFrames[j].line > 0:
-      add(result, ", line: ")
-      add(result, $tempFrames[j].line)
     add(result, "\n")
 
 proc rawWriteStackTrace(): string =