Add work-in-progress implementation of a new Python parser

mypy/cache.py

@@ -266,6 +266,8 @@ def read(cls, data: ReadBuffer, data_file: str) -> CacheMeta | None:
 # Misc classes.
 EXTRA_ATTRS: Final[Tag] = 150
 DT_SPEC: Final[Tag] = 151
+# Four integers representing source file (line, column) range.
+LOCATION: Final[Tag] = 152
 
 END_TAG: Final[Tag] = 255
 

mypy/main.py

@@ -1245,6 +1245,8 @@ def add_invertible_flag(
     # --local-partial-types disallows partial types spanning module top level and a function
     # (implicitly defined in fine-grained incremental mode)
     add_invertible_flag("--local-partial-types", default=False, help=argparse.SUPPRESS)
+    # --native-parser enables the native parser (experimental)
+    add_invertible_flag("--native-parser", default=False, help=argparse.SUPPRESS)
     # --logical-deps adds some more dependencies that are not semantically needed, but
     # may be helpful to determine relative importance of classes and functions for overall
     # type precision in a code base. It also _removes_ some deps, so this flag should be never