Fix Location#end_column

Author: andyw8

lib/yarp.rb

@@ -95,7 +95,7 @@ def start_column
     # The column number in bytes where this location ends from the start of the
     # line.
     def end_column
-      source.column(end_offset - 1)
+      source.column(end_offset)
     end
 
     def deconstruct_keys(keys)

test/yarp/location_test.rb

@@ -817,6 +817,14 @@ def assert_location(kind, source, expected = 0...source.length)
       node = result.value.statements.body.last
       node = yield node if block_given?
 
+      if expected.begin == 0
+        assert_equal 0, node.location.start_column
+      end
+
+      if expected.end == source.length
+        assert_equal source.split("\n").last.length, node.location.end_column
+      end
+
       assert_kind_of kind, node
       assert_equal expected.begin, node.location.start_offset
       assert_equal expected.end, node.location.end_offset