Improve raw_ostream so that you can "write" colors using operator<<

1. raw_ostream supports ANSI colors so that you can write messages to
the termina with colors. Previously, in order to change and reset
color, you had to call `changeColor` and `resetColor` functions,
respectively.

So, if you print out "error: " in red, for example, you had to do
something like this:

  OS.changeColor(raw_ostream::RED);
  OS << "error: ";
  OS.resetColor();

With this patch, you can write the same code as follows:

  OS << raw_ostream::RED << "error: " << raw_ostream::RESET;

2. Add a boolean flag to raw_ostream so that you can disable colored
output. If you disable colors, changeColor, operator<<(Color),
resetColor and other color-related functions have no effect.

Most LLVM tools automatically prints out messages using colors, and
you can disable it by passing a flag such as `--disable-colors`.
This new flag makes it easy to write code that works that way.

Differential Revision: https://reviews.llvm.org/D65564

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@367649 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/AST/ASTDumperUtils.h b/include/clang/AST/ASTDumperUtils.h
index 55a085449a9b2e266f7da4ee8c4643fc0225da61..3dd4f9c081431ae4ebe8cf8bcec2ee80e8e7c651 100644 (file)
--- a/include/clang/AST/ASTDumperUtils.h
+++ b/include/clang/AST/ASTDumperUtils.h
@@ -27,7 +27,7 @@ enum ASTDumpOutputFormat {
 // Do not use bold yellow for any text.  It is hard to read on white screens.
 
 struct TerminalColor {
-  llvm::raw_ostream::Colors Color;
+  llvm::raw_ostream::Color Color;
   bool Bold;
 };
 

diff --git a/lib/Analysis/CFG.cpp b/lib/Analysis/CFG.cpp
index 0ed1e988a196ae7793a333b8ce80aab579890349..5db15077ce3f8817ac3d23a12407f82c94927bad 100644 (file)
--- a/lib/Analysis/CFG.cpp
+++ b/lib/Analysis/CFG.cpp
@@ -5509,7 +5509,7 @@ static void print_block(raw_ostream &OS, const CFG* cfg,
   if (print_edges) {
     // Print the predecessors of this block.
     if (!B.pred_empty()) {
-      const raw_ostream::Colors Color = raw_ostream::BLUE;
+      const raw_ostream::Color Color = raw_ostream::BLUE;
       if (ShowColors)
         OS.changeColor(Color);
       OS << "   Preds " ;
@@ -5546,7 +5546,7 @@ static void print_block(raw_ostream &OS, const CFG* cfg,
 
     // Print the successors of this block.
     if (!B.succ_empty()) {
-      const raw_ostream::Colors Color = raw_ostream::MAGENTA;
+      const raw_ostream::Color Color = raw_ostream::MAGENTA;
       if (ShowColors)
         OS.changeColor(Color);
       OS << "   Succs ";

diff --git a/lib/Frontend/CompilerInvocation.cpp b/lib/Frontend/CompilerInvocation.cpp
index 6bf4fbcbb21ba806979be2c2a4124a954ac5f467..d9bbe2538105847bc3a34a7d3c62a7f16855b039 100644 (file)
--- a/lib/Frontend/CompilerInvocation.cpp
+++ b/lib/Frontend/CompilerInvocation.cpp
@@ -1491,6 +1491,10 @@ bool clang::ParseDiagnosticArgs(DiagnosticOptions &Opts, ArgList &Args,
                    OPT_fno_diagnostics_show_option, DefaultShowOpt);
 
   llvm::sys::Process::UseANSIEscapeCodes(Args.hasArg(OPT_fansi_escape_codes));
+  if (Opts.ShowColors) {
+    llvm::outs().enable_colors();
+    llvm::errs().enable_colors();
+  }
 
   // Default behavior is to not to show note include stacks.
   Opts.ShowNoteIncludeStack = false;

diff --git a/lib/Frontend/TextDiagnostic.cpp b/lib/Frontend/TextDiagnostic.cpp
index d6e75a9180cf54d2ee0e6ae938a3f972a45b8f30..d066ce06715517fb234ddf92d198a1d591c8f098 100644 (file)
--- a/lib/Frontend/TextDiagnostic.cpp
+++ b/lib/Frontend/TextDiagnostic.cpp
@@ -23,23 +23,16 @@
 
 using namespace clang;
 
-static const enum raw_ostream::Colors noteColor =
-  raw_ostream::BLACK;
-static const enum raw_ostream::Colors remarkColor =
-  raw_ostream::BLUE;
-static const enum raw_ostream::Colors fixitColor =
-  raw_ostream::GREEN;
-static const enum raw_ostream::Colors caretColor =
-  raw_ostream::GREEN;
-static const enum raw_ostream::Colors warningColor =
-  raw_ostream::MAGENTA;
-static const enum raw_ostream::Colors templateColor =
-  raw_ostream::CYAN;
-static const enum raw_ostream::Colors errorColor = raw_ostream::RED;
-static const enum raw_ostream::Colors fatalColor = raw_ostream::RED;
+static const raw_ostream::Color noteColor = raw_ostream::BLACK;
+static const raw_ostream::Color remarkColor = raw_ostream::BLUE;
+static const raw_ostream::Color fixitColor = raw_ostream::GREEN;
+static const raw_ostream::Color caretColor = raw_ostream::GREEN;
+static const raw_ostream::Color warningColor = raw_ostream::MAGENTA;
+static const raw_ostream::Color templateColor = raw_ostream::CYAN;
+static const raw_ostream::Color errorColor = raw_ostream::RED;
+static const raw_ostream::Color fatalColor = raw_ostream::RED;
 // Used for changing only the bold attribute.
-static const enum raw_ostream::Colors savedColor =
-  raw_ostream::SAVEDCOLOR;
+static const raw_ostream::Color savedColor = raw_ostream::SAVEDCOLOR;
 
 /// Add highlights to differences in template strings.
 static void applyTemplateHighlighting(raw_ostream &OS, StringRef Str,

diff --git a/tools/diagtool/TreeView.cpp b/tools/diagtool/TreeView.cpp
index 154c52a485afb8b4350a390bbe36ec9d76a4bace..9bb710775d00252f57da60168b8f63f8e6065ad6 100644 (file)
--- a/tools/diagtool/TreeView.cpp
+++ b/tools/diagtool/TreeView.cpp
@@ -20,29 +20,16 @@ DEF_DIAGTOOL("tree", "Show warning flags in a tree view", TreeView)
 using namespace clang;
 using namespace diagtool;
 
-static bool hasColors(const llvm::raw_ostream &out) {
-  if (&out != &llvm::errs() && &out != &llvm::outs())
-    return false;
-  return llvm::errs().is_displayed() && llvm::outs().is_displayed();
-}
-
 class TreePrinter {
+  using Color = llvm::raw_ostream::Color;
+
 public:
   llvm::raw_ostream &out;
-  const bool ShowColors;
   bool Internal;
 
-  TreePrinter(llvm::raw_ostream &out)
-      : out(out), ShowColors(hasColors(out)), Internal(false) {}
-
-  void setColor(llvm::raw_ostream::Colors Color) {
-    if (ShowColors)
-      out << llvm::sys::Process::OutputColor(Color, false, false);
-  }
-
-  void resetColor() {
-    if (ShowColors)
-      out << llvm::sys::Process::ResetColor();
+  TreePrinter(llvm::raw_ostream &out) : out(out), Internal(false) {
+    if (&out != &llvm::errs() && &out != &llvm::outs())
+      out.disable_colors();
   }
 
   static bool isIgnored(unsigned DiagID) {
@@ -70,12 +57,11 @@ public:
     out.indent(Indent * 2);
 
     if (enabledByDefault(Group))
-      setColor(llvm::raw_ostream::GREEN);
+      out << Color::GREEN;
     else
-      setColor(llvm::raw_ostream::YELLOW);
+      out << Color::YELLOW;
 
-    out << "-W" << Group.getName() << "\n";
-    resetColor();
+    out << "-W" << Group.getName() << "\n" << Color::RESET;
 
     ++Indent;
     for (const GroupRecord &GR : Group.subgroups()) {
@@ -84,12 +70,10 @@ public:
 
     if (Internal) {
       for (const DiagnosticRecord &DR : Group.diagnostics()) {
-        if (ShowColors && !isIgnored(DR.DiagID))
-          setColor(llvm::raw_ostream::GREEN);
+        if (!isIgnored(DR.DiagID))
+          out << Color::GREEN;
         out.indent(Indent * 2);
-        out << DR.getName();
-        resetColor();
-        out << "\n";
+        out << DR.getName() << Color::RESET << "\n";
       }
     }
   }
@@ -135,13 +119,9 @@ public:
   }
 
   void showKey() {
-    if (ShowColors) {
-      out << '\n';
-      setColor(llvm::raw_ostream::GREEN);
-      out << "GREEN";
-      resetColor();
-      out << " = enabled by default\n\n";
-    }
+    out << '\n'
+        << Color::GREEN << "GREEN" << Color::RESET
+        << " = enabled by default\n\n";
   }
 };