Make the fire red on black-and-white terminals (#6748)

packages/flutter_tools/lib/src/base/logger.dart

@@ -26,7 +26,7 @@ abstract class Logger {
 
   /// Display normal output of the command. This should be used for things like
   /// progress messages, success messages, or just normal command output.
-  void printStatus(String message, { bool emphasis: false, bool newline: true });
+  void printStatus(String message, { bool emphasis: false, bool newline: true, String ansiAlternative });
 
   /// Use this for verbose tracing output. Users can turn this output on in order
   /// to help diagnose issues with the toolchain or with their setup.
@@ -60,14 +60,16 @@ class StdoutLogger extends Logger {
   }
 
   @override
-  void printStatus(String message, { bool emphasis: false, bool newline: true }) {
+  void printStatus(String message, { bool emphasis: false, bool newline: true, String ansiAlternative }) {
     _status?.cancel();
     _status = null;
-
+    if (terminal.supportsColor && ansiAlternative != null)
+      message = ansiAlternative;
+    if (emphasis)
+      message = terminal.bolden(message);
     if (newline)
-      stdout.writeln(emphasis ? terminal.writeBold(message) : message);
-    else
-      stdout.write(emphasis ? terminal.writeBold(message) : message);
+      message = '$message\n';
+    stdout.write(message);
   }
 
   @override
@@ -106,7 +108,7 @@ class BufferLogger extends Logger {
   void printError(String message, [StackTrace stackTrace]) => _error.writeln(message);
 
   @override
-  void printStatus(String message, { bool emphasis: false, bool newline: true }) {
+  void printStatus(String message, { bool emphasis: false, bool newline: true, String ansiAlternative }) {
     if (newline)
       _status.writeln(message);
     else
@@ -139,7 +141,7 @@ class VerboseLogger extends Logger {
   }
 
   @override
-  void printStatus(String message, { bool emphasis: false, bool newline: true }) {
+  void printStatus(String message, { bool emphasis: false, bool newline: true, String ansiAlternative }) {
     _emit(_LogType.status, message);
   }
 
@@ -168,7 +170,7 @@ class VerboseLogger extends Logger {
     } else {
       prefix = '+$millis ms'.padLeft(prefixWidth);
       if (millis >= 100)
-        prefix = terminal.writeBold(prefix);
+        prefix = terminal.bolden(prefix);
     }
     prefix = '[$prefix] ';
 
@@ -176,11 +178,11 @@ class VerboseLogger extends Logger {
     String indentMessage = message.replaceAll('\n', '\n$indent');
 
     if (type == _LogType.error) {
-      stderr.writeln(prefix + terminal.writeBold(indentMessage));
+      stderr.writeln(prefix + terminal.bolden(indentMessage));
       if (stackTrace != null)
         stderr.writeln(indent + stackTrace.toString().replaceAll('\n', '\n$indent'));
     } else if (type == _LogType.status) {
-      print(prefix + terminal.writeBold(indentMessage));
+      print(prefix + terminal.bolden(indentMessage));
     } else {
       print(prefix + indentMessage);
     }
@@ -210,7 +212,7 @@ class AnsiTerminal {
 
   bool supportsColor;
 
-  String writeBold(String str) => supportsColor ? '$_bold$str$_reset' : str;
+  String bolden(String str) => supportsColor ? '$_bold$str$_reset' : str;
 
   String clearScreen() => supportsColor ? _clear : '\n\n';
 

packages/flutter_tools/lib/src/commands/daemon.dart

@@ -624,7 +624,7 @@ class NotifyingLogger extends Logger {
   }
 
   @override
-  void printStatus(String message, { bool emphasis: false, bool newline: true }) {
+  void printStatus(String message, { bool emphasis: false, bool newline: true, String ansiAlternative }) {
     _messageController.add(new LogMessage('status', message));
   }
 
@@ -698,7 +698,7 @@ class _AppRunLogger extends Logger {
   }
 
   @override
-  void printStatus(String message, { bool emphasis: false, bool newline: true }) {
+  void printStatus(String message, { bool emphasis: false, bool newline: true, String ansiAlternative }) {
     _sendLogEvent(<String, dynamic>{ 'log': message });
   }
 

packages/flutter_tools/lib/src/globals.dart

@@ -27,8 +27,15 @@ void printError(String message, [StackTrace stackTrace]) => logger.printError(me
 
 /// Display normal output of the command. This should be used for things like
 /// progress messages, success messages, or just normal command output.
-void printStatus(String message, { bool emphasis: false, bool newline: true }) {
-  logger.printStatus(message, emphasis: emphasis, newline: newline);
+///
+/// Set `emphasis` to true to make the output bold if it's supported.
+///
+/// Set `newline` to false to skip the trailing linefeed.
+///
+/// If `ansiAlternative` is provided, and the terminal supports color, that
+/// string will be printed instead of the message.
+void printStatus(String message, { bool emphasis: false, bool newline: true, String ansiAlternative }) {
+  logger.printStatus(message, emphasis: emphasis, newline: newline, ansiAlternative: ansiAlternative);
 }
 
 /// Use this for verbose tracing output. Users can turn this output on in order

packages/flutter_tools/lib/src/hot.dart

@@ -594,7 +594,15 @@ class HotRunner extends ResidentRunner {
 
   @override
   void printHelp({ @required bool details }) {
-    printStatus('🔥  To hot reload your app on the fly, press "r" or F5. To restart the app entirely, press "R".', emphasis: true);
+    const String fire = '🔥';
+    const String redOnBlack = '\u001B[31;40m';
+    const String bold = '\u001B[0;1m';
+    const String reset = '\u001B[0m';
+    printStatus(
+      '$fire  To hot reload your app on the fly, press "r" or F5. To restart the app entirely, press "R".',
+      ansiAlternative: '$redOnBlack$fire$bold  To ${redOnBlack}hot reload$bold your app on the fly, '
+                       'press "r" or F5. To restart the app entirely, press "R".$reset'
+    );
     printStatus('The Observatory debugger and profiler is available at: http://127.0.0.1:$_observatoryPort/');
     if (details) {
       printStatus('To dump the widget hierarchy of the app (debugDumpApp), press "w".');