Enable to get column position on error (#43)

* Enabled to get column position on error

* I made an error when there was no character indicating position.

* I made it impossible to fail with rspec without setting charactor。

* Added start and end to character

* Fixed by rubocop

* Deleted unnecessary white spaces.

Author: steiley

lib/language_server.rb

@@ -118,11 +118,11 @@ def on(method, &callback)
         range: Protocol::Interface::Range.new(
           start: Protocol::Interface::Position.new(
             line: error.line_num,
-            character: 0,
+            character: error.characters.min,
           ),
           end: Protocol::Interface::Position.new(
             line: error.line_num,
-            character: 0,
+            character: error.characters.max,
           ),
         ),
       )

lib/language_server/linter/ruby_wc.rb

@@ -3,10 +3,11 @@
 module LanguageServer
   module Linter
     class Error
-      attr_reader :line_num, :message, :type
+      attr_reader :line_num, :characters, :message, :type
 
-      def initialize(line_num:, message:, type:)
+      def initialize(line_num:, characters: 0..0, message:, type:)
         @line_num = line_num
+        @characters = characters
         @message = message
         @type = type
       end
@@ -16,7 +17,7 @@ def warning?
       end
 
       def ==(other)
-        line_num == other.line_num && message == other.message
+        line_num == other.line_num && characters == other.characters && message == other.message
       end
     end
 
@@ -27,7 +28,7 @@ def initialize(source)
 
       def call
         error_message.scan(/.+:(\d+):\s*(.+?)[,:]\s(.+)/).map do |line_num, type, message|
-          Error.new(line_num: line_num.to_i - 1, message: message, type: type)
+          Error.new(line_num: line_num.to_i - 1, characters: get_characters_from_error_message(error_message, line_num.to_i - 1), message: message, type: type)
         end
       end
 
@@ -75,6 +76,16 @@ def capture_stderr
         ensure
           $stderr = origin
         end
+
+        def get_characters_from_error_message(error_message, line_index)
+          error_mark_included_line = error_message.split("\n")[2]
+
+          if !error_mark_included_line.nil? && character_start = error_mark_included_line.index("^")
+            Range.new(character_start, character_start + 1)
+          else
+            Range.new(0, @source.split("\n")[line_index].length - 1)
+          end
+        end
     end
   end
 end

test/language_server/linter/ruby_wc_test.rb

@@ -9,7 +9,7 @@ def test_error
       EOS
 
       assert {
-        linter.call == [Error.new(line_num: 1, message: "unexpected $undefined, expecting end-of-input", type: "syntax error")]
+        linter.call == [Error.new(line_num: 1, characters: 10..11, message: "unexpected $undefined, expecting end-of-input", type: "syntax error")]
       }
     end
 
@@ -19,7 +19,7 @@ def test_warn
       EOS
 
       assert {
-        linter.call == [Error.new(line_num: 0, message: "assigned but unused variable - a", type: "warning")]
+        linter.call == [Error.new(line_num: 0, characters: 0..4, message: "assigned but unused variable - a", type: "warning")]
       }
     end
   end