gh-104683: Argument Clinic: Extract parse_function_names() helper

Lib/test/test_clinic.py

@@ -682,7 +682,7 @@ class C "void *" ""
  foo2 as .illegal. = foo1
  [clinic start generated code]*/
  """
- err = "Illegal C basename: '.illegal. = foo1'"
+ err = "Illegal C basename: '.illegal.'"
  self.expect_failure(block, err, lineno=7)
 
 

Tools/clinic/clinic.py

@@ -1674,18 +1674,8 @@ def render_function(
  full_name = f.full_name
  template_dict = {'full_name': full_name}
  template_dict['name'] = f.displayname
-
- if f.c_basename:
- c_basename = f.c_basename
- else:
- fields = full_name.split(".")
- if fields[-1] == '__new__':
- fields.pop()
- c_basename = "_".join(fields)
-
- template_dict['c_basename'] = c_basename
-
- template_dict['methoddef_name'] = c_basename.upper() + "_METHODDEF"
+ template_dict['c_basename'] = f.c_basename
+ template_dict['methoddef_name'] = f.c_basename.upper() + "_METHODDEF"
 
  template_dict['docstring'] = self.docstring_for_c_string(f)
 
@@ -2653,7 +2643,7 @@ class Function:
  name: str
  module: Module | Clinic
  cls: Class | None
- c_basename: str | None
+ c_basename: str
  full_name: str
  return_converter: CReturnConverter
  kind: FunctionKind
@@ -4577,6 +4567,11 @@ class ParamState(enum.IntEnum):
  RIGHT_SQUARE_AFTER = 6
 
 
+class FunctionNames(NamedTuple):
+ full_name: str
+ c_basename: str
+
+
 class DSLParser:
  function: Function | None
  state: StateKeeper
@@ -4840,6 +4835,24 @@ def state_dsl_start(self, line: str) -> None:
 
  self.next(self.state_modulename_name, line)
 
+ @staticmethod
+ def parse_function_names(line: str) -> FunctionNames:
+ left, as_, right = line.partition(' as ')
+ full_name = left.strip()
+ c_basename = right.strip()
+ if as_ and not c_basename:
+ fail("No C basename provided after 'as' keyword")
+ if not c_basename:
+ fields = full_name.split(".")
+ if fields[-1] == '__new__':
+ fields.pop()
+ c_basename = "_".join(fields)
+ if not is_legal_py_identifier(full_name):
+ fail(f"Illegal function name: {full_name!r}")
+ if not is_legal_c_identifier(c_basename):
+ fail(f"Illegal C basename: {c_basename!r}")
+ return FunctionNames(full_name=full_name, c_basename=c_basename)
+
  def update_function_kind(self, fullname: str) -> None:
  fields = fullname.split('.')
  name = fields.pop()
@@ -4877,17 +4890,10 @@ def state_modulename_name(self, line: str) -> None:
 
  # are we cloning?
  before, equals, existing = line.rpartition('=')
- c_basename: str | None
  if equals:
- full_name, as_, c_basename = before.partition(' as ')
- full_name = full_name.strip()
- c_basename = c_basename.strip()
- if as_ and not c_basename:
- fail("No C basename provided after 'as' keyword")
+ full_name, c_basename = self.parse_function_names(before)
  existing = existing.strip()
- if (is_legal_py_identifier(full_name) and
- (not c_basename or is_legal_c_identifier(c_basename)) and
- is_legal_py_identifier(existing)):
+ if is_legal_py_identifier(existing):
  # we're cloning!
  fields = [x.strip() for x in existing.split('.')]
  function_name = fields.pop()
@@ -4933,16 +4939,7 @@ def state_modulename_name(self, line: str) -> None:
 
  line, _, returns = line.partition('->')
  returns = returns.strip()
-
- full_name, as_, c_basename = line.partition(' as ')
- full_name = full_name.strip()
- c_basename = c_basename.strip() or None
- if as_ and not c_basename:
- fail("No C basename provided after 'as' keyword")
- if not is_legal_py_identifier(full_name):
- fail(f"Illegal function name: {full_name!r}")
- if c_basename and not is_legal_c_identifier(c_basename):
- fail(f"Illegal C basename: {c_basename!r}")
+ full_name, c_basename = self.parse_function_names(line)
 
  return_converter = None
  if returns: