fix https://github.com/timotheecour/Nim/issues/152: avoid writing spurious ^[[0m to stderr when callStyledWriteLineStderr not called (#14214)

* fix https://github.com/timotheecour/Nim/issues/152 `^[[0m` is inserted in stderr for `echo code | nim c -`

* resetAttributes not even needed, already handled in styledWriteLine

* simplify tests in tests/trunner.nim thanks to this fix

compiler/main.nim

@@ -405,5 +405,3 @@ proc mainCommand*(graph: ModuleGraph) =
     echo "  int tries: ", gCacheIntTries
     echo "  efficiency: ", formatFloat(1-(gCacheMisses.float/gCacheTries.float),
                                        ffDecimal, 3)
-
-  resetAttributes(conf)

compiler/msgs.nim

@@ -298,6 +298,9 @@ macro callStyledWriteLineStderr(args: varargs[typed]): untyped =
   result.add(bindSym"stderr")
   for arg in children(args[0][1]):
     result.add(arg)
+  when false:
+    # not needed because styledWriteLine already ends with resetAttributes
+    result = newStmtList(result, newCall(bindSym"resetAttributes", bindSym"stderr"))
 
 template callWritelnHook(args: varargs[string, `$`]) =
   conf.writelnHook concat(args)
@@ -441,10 +444,6 @@ proc rawMessage*(conf: ConfigRef; msg: TMsgKind, args: openArray[string]) =
 proc rawMessage*(conf: ConfigRef; msg: TMsgKind, arg: string) =
   rawMessage(conf, msg, [arg])
 
-proc resetAttributes*(conf: ConfigRef) =
-  if {optUseColors, optStdout} * conf.globalOptions == {optUseColors}:
-    terminal.resetAttributes(stderr)
-
 proc addSourceLine(conf: ConfigRef; fileIdx: FileIndex, line: string) =
   conf.m.fileInfos[fileIdx.int32].lines.add line
 

tests/trunner.nim

@@ -74,9 +74,7 @@ else: # don't run twice the same test
       var output = p.outputStream.readAll
       let error = p.errorStream.readAll
       doAssert p.waitForExit == 0
-      when false: # https://github.com/timotheecour/Nim/issues/152
+      doAssert error.len == 0, $error
-        # bug: `^[[0m` is being inserted somehow with `-` (regarless of --run)
-        doAssert error.len == 0, $(error,)
       output.stripLineEnd
       doAssert output == expected
       p.errorStream.close
@@ -85,8 +83,6 @@ else: # don't run twice the same test
     block:
       when defined(posix):
         let cmd = fmt"echo 'import os; echo commandLineParams()' | {nimcmd}"
-        # avoid https://github.com/timotheecour/Nim/issues/152 by
+        var (output, exitCode) = execCmdEx(cmd)
-        # making sure `poStdErrToStdOut` isn't passed
-        var (output, exitCode) = execCmdEx(cmd, options = {poEvalCommand})
         output.stripLineEnd
         doAssert output == expected