Merge pull request #15 from mtsmfm/log-with-color

Log with color

Author: mtsmfm

lib/language_server.rb

@@ -1,4 +1,5 @@
 require "language_server/version"
+require "language_server/logger"
 require "language_server/protocol/interfaces"
 require "language_server/protocol/constants"
 require "language_server/protocol/stdio"
@@ -9,14 +10,9 @@
 require "language_server/project"
 
 require "json"
-require "logger"
 
 module LanguageServer
   class << self
-    def logger
-      @logger ||= Logger.new(STDERR)
-    end
-
     def run
       writer = Protocol::Stdio::Writer.new
       reader = Protocol::Stdio::Reader.new

lib/language_server/logger.rb

@@ -0,0 +1,37 @@
+require 'logger'
+
+module LanguageServer
+  class << self
+    def logger
+      @logger ||= ::Logger.new(STDERR, formatter: Formatter.new)
+    end
+  end
+
+  class Formatter
+    RESET = "\e[0m"
+    RED = "\e[31m"
+    YELLOW = "\e[33m"
+
+    def call(severity, *rest)
+      msg = default_message(severity, *rest)
+      case severity
+      when 'ERROR'
+        RED + msg + RESET
+      when 'WARN'
+        YELLOW + msg + RESET
+      else
+        msg
+      end
+    end
+
+    private
+
+    def default_message(*args)
+      default_formatter.call(*args)
+    end
+
+    def default_formatter
+      @default_formatter ||= ::Logger::Formatter.new
+    end
+  end
+end