fix .freeze(), improve tests

pathod/language/base.py

@@ -578,4 +578,4 @@ class NestedMessage(Token):
 
     def freeze(self, settings):
         f = self.parsed.freeze(settings).spec()
-        return self.__class__(TokValueLiteral(strutils.bytes_to_escaped_str(f)))
+        return self.__class__(TokValueLiteral(strutils.bytes_to_escaped_str(f.encode())))

test/pathod/test_language_base.py

@@ -55,8 +55,15 @@ class TestTokValueLiteral:
         v = base.TokValueLiteral("f\x00oo")
         assert v.spec() == repr(v) == r"'f\x00oo'"
 
-        v = base.TokValueLiteral("\"")
-        assert v.spec() == repr(v) == '\'"\''
+        v = base.TokValueLiteral('"')
+        assert v.spec() == repr(v) == """  '"'  """.strip()
+
+        # While pyparsing has a escChar argument for QuotedString,
+        # escChar only performs scapes single-character escapes and does not work for e.g. r"\x02".
+        # Thus, we cannot use that option, which means we cannot have single quotes in strings.
+        # To fix this, we represent single quotes as r"\x07".
+        v = base.TokValueLiteral("'")
+        assert v.spec() == r"'\x27'"
 
     def roundtrip(self, spec):
         e = base.TokValueLiteral.expr()

test/pathod/test_language_http.py

@@ -340,9 +340,7 @@ def test_nested_response():
 def test_nested_response_freeze():
     e = http.NestedResponse(
         base.TokValueLiteral(
-            "200:b'foo':i10,'\\x27'".encode(
-                "string_escape"
-            )
+            r"200:b\'foo\':i10,\'\\x27\'"
         )
     )
     assert e.freeze({})