Update sys.version_info guards after dropping Python 3.8 (#18338)

Author: cdce8p

mypy/fastparse.py

@@ -1,6 +1,5 @@
 from __future__ import annotations
 
-import copy
 import re
 import sys
 import warnings
@@ -241,13 +240,6 @@ def parse(
             path=fnam,
         ).visit(ast)
     except SyntaxError as e:
-        # alias to please mypyc
-        is_py38_or_earlier = sys.version_info < (3, 9)
-        if is_py38_or_earlier and e.filename == "<fstring>":
-            # In Python 3.8 and earlier, syntax errors in f-strings have lineno relative to the
-            # start of the f-string. This would be misleading, as mypy will report the error as the
-            # lineno within the file.
-            e.lineno = None
         message = e.msg
         if feature_version > sys.version_info.minor and message.startswith("invalid syntax"):
             python_version_str = f"{options.python_version[0]}.{options.python_version[1]}"
@@ -2069,40 +2061,15 @@ def visit_Index(self, n: ast3.Index) -> Type:
     def visit_Slice(self, n: ast3.Slice) -> Type:
         return self.invalid_type(n, note="did you mean to use ',' instead of ':' ?")
 
-    # Subscript(expr value, slice slice, expr_context ctx)  # Python 3.8 and before
     # Subscript(expr value, expr slice, expr_context ctx)  # Python 3.9 and later
     def visit_Subscript(self, n: ast3.Subscript) -> Type:
-        if sys.version_info >= (3, 9):  # Really 3.9a5 or later
-            sliceval: Any = n.slice
-        # Python 3.8 or earlier use a different AST structure for subscripts
-        elif isinstance(n.slice, ast3.Index):
-            sliceval: Any = n.slice.value
-        elif isinstance(n.slice, ast3.Slice):
-            sliceval = copy.deepcopy(n.slice)  # so we don't mutate passed AST
-            if getattr(sliceval, "col_offset", None) is None:
-                # Fix column information so that we get Python 3.9+ message order
-                sliceval.col_offset = sliceval.lower.col_offset
-        else:
-            assert isinstance(n.slice, ast3.ExtSlice)
-            dims = cast(List[ast3.expr], copy.deepcopy(n.slice.dims))
-            for s in dims:
-                # These fields don't actually have a col_offset attribute but we add
-                # it manually.
-                if getattr(s, "col_offset", None) is None:
-                    if isinstance(s, ast3.Index):
-                        s.col_offset = s.value.col_offset
-                    elif isinstance(s, ast3.Slice):
-                        assert s.lower is not None
-                        s.col_offset = s.lower.col_offset
-            sliceval = ast3.Tuple(dims, n.ctx)
-
         empty_tuple_index = False
-        if isinstance(sliceval, ast3.Tuple):
-            params = self.translate_expr_list(sliceval.elts)
-            if len(sliceval.elts) == 0:
+        if isinstance(n.slice, ast3.Tuple):
+            params = self.translate_expr_list(n.slice.elts)
+            if len(n.slice.elts) == 0:
                 empty_tuple_index = True
         else:
-            params = [self.visit(sliceval)]
+            params = [self.visit(n.slice)]
 
         value = self.visit(n.value)
         if isinstance(value, UnboundType) and not value.args:

mypy/pyinfo.py

@@ -2,9 +2,9 @@
 
 """Utilities to find the site and prefix information of a Python executable.
 
-This file MUST remain compatible with all Python 3.8+ versions. Since we cannot make any
+This file MUST remain compatible with all Python 3.9+ versions. Since we cannot make any
 assumptions about the Python being executed, this module should not use *any* dependencies outside
-of the standard library found in Python 3.8. This file is run each mypy run, so it should be kept
+of the standard library found in Python 3.9. This file is run each mypy run, so it should be kept
 as fast as possible.
 """
 import sys

mypy/test/testcheck.py

@@ -37,8 +37,6 @@
 typecheck_files = find_test_files(pattern="check-*.test")
 
 # Tests that use Python version specific features:
-if sys.version_info < (3, 9):
-    typecheck_files.remove("check-python39.test")
 if sys.version_info < (3, 10):
     typecheck_files.remove("check-python310.test")
 if sys.version_info < (3, 11):

mypy/test/testpep561.py

@@ -52,7 +52,6 @@ def upgrade_pip(python_executable: str) -> None:
         sys.version_info >= (3, 11)
         or (3, 10, 3) <= sys.version_info < (3, 11)
         or (3, 9, 11) <= sys.version_info < (3, 10)
-        or (3, 8, 13) <= sys.version_info < (3, 9)
     ):
         # Skip for more recent Python releases which come with pip>=21.3.1
         # out of the box - for performance reasons.

mypy/test/teststubtest.py

@@ -1533,12 +1533,11 @@ def test_dunders(self) -> Iterator[Case]:
             runtime="class C:\n  def __init_subclass__(cls, e=1, **kwargs): pass",
             error=None,
         )
-        if sys.version_info >= (3, 9):
-            yield Case(
-                stub="class D:\n  def __class_getitem__(cls, type: type) -> type: ...",
-                runtime="class D:\n  def __class_getitem__(cls, type): ...",
-                error=None,
-            )
+        yield Case(
+            stub="class D:\n  def __class_getitem__(cls, type: type) -> type: ...",
+            runtime="class D:\n  def __class_getitem__(cls, type): ...",
+            error=None,
+        )
 
     @collect_cases
     def test_not_subclassable(self) -> Iterator[Case]:

mypy/util.py

@@ -30,15 +30,7 @@
 
 T = TypeVar("T")
 
-if sys.version_info >= (3, 9):
-    TYPESHED_DIR: Final = str(importlib_resources.files("mypy") / "typeshed")
-else:
-    with importlib_resources.path(
-        "mypy",  # mypy-c doesn't support __package__
-        "py.typed",  # a marker file for type information, we assume typeshed to live in the same dir
-    ) as _resource:
-        TYPESHED_DIR = str(_resource.parent / "typeshed")
-
+TYPESHED_DIR: Final = str(importlib_resources.files("mypy") / "typeshed")
 
 ENCODING_RE: Final = re.compile(rb"([ \t\v]*#.*(\r\n?|\n))??[ \t\v]*#.*coding[:=][ \t]*([-\w.]+)")
 
@@ -490,7 +482,7 @@ def get_unique_redefinition_name(name: str, existing: Container[str]) -> str:
 def check_python_version(program: str) -> None:
     """Report issues with the Python used to run mypy, dmypy, or stubgen"""
     # Check for known bad Python versions.
-    if sys.version_info[:2] < (3, 9):
+    if sys.version_info[:2] < (3, 9):  # noqa: UP036, RUF100
         sys.exit(
             "Running {name} with Python 3.8 or lower is not supported; "
             "please upgrade to 3.9 or newer".format(name=program)

setup.py

@@ -8,7 +8,7 @@
 import sys
 from typing import TYPE_CHECKING, Any
 
-if sys.version_info < (3, 9, 0):
+if sys.version_info < (3, 9, 0):  # noqa: UP036, RUF100
     sys.stderr.write("ERROR: You need Python 3.9 or later to use mypy.\n")
     exit(1)