fix: fix a parser hang

tests/test_parser.py

@@ -51,3 +51,15 @@ def test_parse_multiline_string_ignore_the_first_newline() -> None:
     content = 'a = """\r\nfoo\n"""'
     parser = Parser(content)
     assert parser.parse() == {"a": "foo\n"}
+
+
+def test_parse_multiline_basic_string_with_crlf() -> None:
+    content = 'a = """foo\r\nbar"""'
+    parser = Parser(content)
+    assert parser.parse() == {"a": "foo\r\nbar"}
+
+
+def test_parse_multiline_literal_string_with_crlf() -> None:
+    content = "a = '''foo\r\nbar'''"
+    parser = Parser(content)
+    assert parser.parse() == {"a": "foo\r\nbar"}

tomlkit/parser.py

@@ -860,6 +860,8 @@ def _parse_string(self, delim: StringType) -> String:
                 with self._state(restore=True):
                     if not self.inc() or self._current != "\n":
                         raise self.parse_error(InvalidControlChar, CTRL_M, "strings")
+                value += self._current
+                self.inc(exception=UnexpectedEofError)
             elif not escaped and self._current == delim.unit:
                 # try to process current as a closing delim
                 original = self.extract()