parse.y: ripper generic input

* parse.y (ripper_initialize): allow generic input as source, if
  it has #gets method.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57022 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

parse.y

@@ -776,7 +776,7 @@ static VALUE parser_heredoc_dedent(struct parser_params*,VALUE);
 # define rb_warning3L(l,fmt,a,b,c)   WARNING_CALL(WARNING_ARGS_L(l, fmt, 4), (a), (b), (c))
 # define rb_warning4L(l,fmt,a,b,c,d) WARNING_CALL(WARNING_ARGS_L(l, fmt, 5), (a), (b), (c), (d))
 #ifdef RIPPER
-static ID id_warn, id_warning;
+static ID id_warn, id_warning, id_gets;
 # define WARN_S_L(s,l) STR_NEW(s,l)
 # define WARN_S(s) STR_NEW2(s)
 # define WARN_I(i) INT2NUM(i)
@@ -11317,6 +11317,18 @@ ripper_compile_error(struct parser_params *parser, const char *fmt, ...)
 
 static VALUE
 ripper_lex_get_generic(struct parser_params *parser, VALUE src)
+{
+    VALUE line = rb_funcallv_public(src, id_gets, 0, 0);
+    if (!NIL_P(line) && !RB_TYPE_P(line, T_STRING)) {
+	rb_raise(rb_eTypeError,
+		 "gets returned %"PRIsVALUE" (expected String or nil)",
+		 rb_obj_class(line));
+    }
+    return line;
+}
+
+static VALUE
+ripper_lex_io_get(struct parser_params *parser, VALUE src)
 {
     return rb_io_gets(src);
 }
@@ -11352,6 +11364,9 @@ ripper_initialize(int argc, VALUE *argv, VALUE self)
     TypedData_Get_Struct(self, struct parser_params, &parser_data_type, parser);
     rb_scan_args(argc, argv, "12", &src, &fname, &lineno);
     if (RB_TYPE_P(src, T_FILE)) {
+        lex_gets = ripper_lex_io_get;
+    }
+    else if (rb_respond_to(src, id_gets)) {
         lex_gets = ripper_lex_get_generic;
     }
     else {
@@ -11519,6 +11534,7 @@ Init_ripper(void)
     ripper_init_eventids2();
     id_warn = rb_intern_const("warn");
     id_warning = rb_intern_const("warning");
+    id_gets = rb_intern_const("gets");
 
     InitVM(ripper);
 }

test/ripper/test_ripper.rb

@@ -117,4 +117,22 @@ end
 
     assert_nothing_raised { Ripper.lex src }
   end
+
+  class TestInput < self
+    Input = Struct.new(:lines) do
+      def gets
+        lines.shift
+      end
+    end
+
+    def setup
+      @ripper = Ripper.new(Input.new(["1 + 1"]))
+    end
+
+    def test_invalid_gets
+      ripper = assert_nothing_raised {Ripper.new(Input.new([0]))}
+      assert_raise(TypeError) {ripper.parse}
+    end
+  end
+
 end if ripper_test