lld: Add --color-diagnostic to MachO port, harmonize others

This adds `--[no-]color-diagnostics[=auto,never,always]` to
the MachO port and harmonizes the flag in the other ports:
- Consistently use MetaVarName
- Consistently document the non-eq version as alias of the eq version
- Use B<> in the ports that have it (no-op, shorter)
- Fix oversight in COFF port that made the --no flag have the wrong
  prefix

Differential Revision: https://reviews.llvm.org/D91640

lld/COFF/Options.td

@@ -33,9 +33,12 @@ def aligncomm : P<"aligncomm", "Set common symbol alignment">;
 def alternatename : P<"alternatename", "Define weak alias">;
 def base    : P<"base", "Base address of the program">;
 def color_diagnostics: Flag<["--"], "color-diagnostics">,
-    HelpText<"Use colors in diagnostics">;
+    HelpText<"Alias for --color-diagnostics=always">;
+def no_color_diagnostics: Flag<["--"], "no-color-diagnostics">,
+    HelpText<"Alias for --color-diagnostics=never">;
 def color_diagnostics_eq: Joined<["--"], "color-diagnostics=">,
-    HelpText<"Use colors in diagnostics; one of 'always', 'never', 'auto'">;
+    HelpText<"Use colors in diagnostics (default: auto)">,
+    MetaVarName<"[auto,always,never]">;
 def defaultlib : P<"defaultlib", "Add the library to the list of input files">;
 def delayload : P<"delayload", "Delay loaded DLL name">;
 def entry   : P<"entry", "Name of entry point symbol">;
@@ -73,8 +76,6 @@ def opt     : P<"opt", "Control optimizations">;
 def order   : P<"order", "Put functions in order">;
 def out     : P<"out", "Path to file to write output">;
 def natvis : P<"natvis", "Path to natvis file to embed in the PDB">;
-def no_color_diagnostics: F<"no-color-diagnostics">,
-    HelpText<"Do not use colors in diagnostics">;
 def pdb : P<"pdb", "PDB file path">;
 def pdbstripped : P<"pdbstripped", "Stripped PDB file path">;
 def pdbaltpath : P<"pdbaltpath", "PDB file path to embed in the image">;

lld/ELF/Options.td

@@ -113,11 +113,11 @@ defm call_graph_profile_sort: BB<"call-graph-profile-sort",
 // -chroot doesn't have a help text because it is an internal option.
 def chroot: Separate<["--", "-"], "chroot">;
 
-def color_diagnostics: F<"color-diagnostics">,
-  HelpText<"Alias for --color-diagnostics=always">;
-
+defm color_diagnostics: B<"color-diagnostics",
+  "Alias for --color-diagnostics=always",
+  "Alias for --color-diagnostics=never">;
 def color_diagnostics_eq: J<"color-diagnostics=">,
-  HelpText<"Use colors in diagnostics">,
+  HelpText<"Use colors in diagnostics (default: auto)">,
   MetaVarName<"[auto,always,never]">;
 
 defm cref: B<"cref",
@@ -274,9 +274,6 @@ def nmagic: F<"nmagic">, MetaVarName<"<magic>">,
 def nostdlib: F<"nostdlib">,
   HelpText<"Only search directories specified on the command line">;
 
-def no_color_diagnostics: F<"no-color-diagnostics">,
-  HelpText<"Do not use colors in diagnostics">;
-
 def no_dynamic_linker: F<"no-dynamic-linker">,
   HelpText<"Inhibit output of .interp section">;
 

lld/MachO/Driver.cpp

@@ -69,6 +69,28 @@ static const opt::OptTable::Info optInfo[] = {
 
 MachOOptTable::MachOOptTable() : OptTable(optInfo) {}
 
+// Set color diagnostics according to --color-diagnostics={auto,always,never}
+// or --no-color-diagnostics flags.
+static void handleColorDiagnostics(opt::InputArgList &args) {
+  auto *arg = args.getLastArg(OPT_color_diagnostics, OPT_color_diagnostics_eq,
+                              OPT_no_color_diagnostics);
+  if (!arg)
+    return;
+  if (arg->getOption().getID() == OPT_color_diagnostics) {
+    lld::errs().enable_colors(true);
+  } else if (arg->getOption().getID() == OPT_no_color_diagnostics) {
+    lld::errs().enable_colors(false);
+  } else {
+    StringRef s = arg->getValue();
+    if (s == "always")
+      lld::errs().enable_colors(true);
+    else if (s == "never")
+      lld::errs().enable_colors(false);
+    else if (s != "auto")
+      error("unknown option: --color-diagnostics=" + s);
+  }
+}
+
 opt::InputArgList MachOOptTable::parse(ArrayRef<const char *> argv) {
   // Make InputArgList from string vectors.
   unsigned missingIndex;
@@ -80,6 +102,8 @@ opt::InputArgList MachOOptTable::parse(ArrayRef<const char *> argv) {
   if (missingCount)
     error(Twine(args.getArgString(missingIndex)) + ": missing argument");
 
+  handleColorDiagnostics(args);
+
   for (opt::Arg *arg : args.filtered(OPT_UNKNOWN))
     error("unknown argument: " + arg->getSpelling());
   return args;

lld/MachO/Options.td

@@ -1,8 +1,20 @@
 include "llvm/Option/OptParser.td"
 
+// Flags that lld/MachO understands but ld64 doesn't. These take
+// '--' instead of '-' and use dashes instead of underscores, so
+// they don't collide with the ld64 compat options.
+
 def help : Flag<["-", "--"], "help">;
 def help_hidden : Flag<["--"], "help-hidden">,
   HelpText<"Display help for hidden options">;
+def color_diagnostics: Flag<["--"], "color-diagnostics">,
+  HelpText<"Alias for --color-diagnostics=always">;
+def no_color_diagnostics: Flag<["--"], "no-color-diagnostics">,
+  HelpText<"Alias for --color-diagnostics=never">;
+def color_diagnostics_eq: Joined<["--"], "color-diagnostics=">,
+  HelpText<"Use colors in diagnostics (default: auto)">,
+  MetaVarName<"[auto,always,never]">;
+
 
 // This is a complete Options.td compiled from Apple's ld(1) manpage
 // dated 2018-03-07 and cross checked with ld64 source code in repo

lld/test/MachO/color-diagnostics.test

@@ -0,0 +1,21 @@
+# Windows command prompt doesn't support ANSI escape sequences.
+# REQUIRES: shell
+
+# RUN: not %lld -xyz --color-diagnostics /nosuchfile 2>&1 \
+# RUN:   | FileCheck -check-prefix=COLOR %s
+# RUN: not %lld -xyz --color-diagnostics=always /nosuchfile 2>&1 \
+# RUN:   | FileCheck -check-prefix=COLOR %s
+
+# COLOR: {{lld: .\[0;31merror: .\[0munknown argument: -xyz}}
+# COLOR: {{lld: .\[0;31merror: .\[0mcannot open /nosuchfile}}
+
+# RUN: not %lld --color-diagnostics=foobar 2>&1 | FileCheck -check-prefix=ERR %s
+# ERR: unknown option: --color-diagnostics=foobar
+
+# RUN: not %lld /nosuchfile 2>&1 | FileCheck -check-prefix=NOCOLOR %s
+# RUN: not %lld --color-diagnostics=never /nosuchfile 2>&1 \
+# RUN:   | FileCheck -check-prefix=NOCOLOR %s
+# RUN: not %lld --color-diagnostics=always --no-color-diagnostics \
+# RUN:   /nosuchfile 2>&1 | FileCheck -check-prefix=NOCOLOR %s
+
+# NOCOLOR: lld: error: cannot open /nosuchfile

lld/wasm/Options.td

@@ -20,11 +20,12 @@ multiclass B<string name, string help1, string help2> {
 // The following flags are shared with the ELF linker
 def Bsymbolic: F<"Bsymbolic">, HelpText<"Bind defined symbols locally">;
 
-def color_diagnostics: F<"color-diagnostics">,
-  HelpText<"Use colors in diagnostics">;
-
+defm color_diagnostics: B<"color-diagnostics",
+  "Alias for --color-diagnostics=always",
+  "Alias for --color-diagnostics=never">;
 def color_diagnostics_eq: J<"color-diagnostics=">,
-  HelpText<"Use colors in diagnostics; one of 'always', 'never', 'auto'">;
+  HelpText<"Use colors in diagnostics (default: auto)">,
+  MetaVarName<"[auto,always,never]">;
 
 def compress_relocations: F<"compress-relocations">,
   HelpText<"Compress the relocation targets in the code section.">;
@@ -70,9 +71,6 @@ def mllvm: S<"mllvm">, HelpText<"Options to pass to LLVM">;
 
 defm Map: Eq<"Map", "Print a link map to the specified file">;
 
-def no_color_diagnostics: F<"no-color-diagnostics">,
-  HelpText<"Do not use colors in diagnostics">;
-
 def no_fatal_warnings: F<"no-fatal-warnings">;
 
 def o: JoinedOrSeparate<["-"], "o">, MetaVarName<"<path>">,