Syntax: fix incorrect handling of "%w(" (#5241)

Author: asterite

spec/compiler/parser/parser_spec.cr

@@ -1598,6 +1598,9 @@ describe "Parser" do
     assert_syntax_error %(case x; when /x/; 2; when /x/; end), "duplicate when /x/ in case"
     assert_syntax_error %(case x; when X; 2; when X; end), "duplicate when X in case"
 
+    assert_syntax_error "%w(", "Unterminated String array literal"
+    assert_syntax_error "%i(", "Unterminated Symbol array literal"
+
     it "gets corrects of ~" do
       node = Parser.parse("\n  ~1")
       loc = node.location.not_nil!

src/compiler/crystal/syntax/lexer.cr

@@ -2438,6 +2438,11 @@ module Crystal
         next_char
       end
 
+      if start == current_pos
+        @token.type = :EOF
+        return @token
+      end
+
       @token.type = :STRING
       @token.value = string_range(start)
       set_token_raw_from_start(start)

src/compiler/crystal/syntax/parser.cr

@@ -2049,8 +2049,8 @@ module Crystal
         when :STRING_ARRAY_END
           next_token
           break
-        when :EOF
-          raise "Unterminated symbol array literal"
+        else
+          raise "Unterminated #{elements_type} array literal"
         end
       end