gh-86457: Fix signature for code.replace() (GH-23199)

Also add support of @text_signature in Argument Clinic.

1 files changed, 133 insertions, 124 deletions

diff --git a/Tools/clinic/clinic.py b/Tools/clinic/clinic.py
index 3a8431c..57ad4e4 100755
--- a/Tools/clinic/clinic.py
+++ b/Tools/clinic/clinic.py
@@ -4595,6 +4595,7 @@ class DSLParser:
         self.indent = IndentStack()
         self.kind = CALLABLE
         self.coexist = False
+        self.forced_text_signature: str | None = None
         self.parameter_continuation = ''
         self.preserve_output = False
 
@@ -4735,6 +4736,11 @@ class DSLParser:
             fail("Called @coexist twice!")
         self.coexist = True
 
+    def at_text_signature(self, text_signature: str) -> None:
+        if self.forced_text_signature:
+            fail("Called @text_signature twice!")
+        self.forced_text_signature = text_signature
+
     def parse(self, block: Block) -> None:
         self.reset()
         self.block = block
@@ -5515,142 +5521,145 @@ class DSLParser:
             add(f.cls.name)
         else:
             add(f.name)
-        add('(')
-
-        # populate "right_bracket_count" field for every parameter
-        assert parameters, "We should always have a self parameter. " + repr(f)
-        assert isinstance(parameters[0].converter, self_converter)
-        # self is always positional-only.
-        assert parameters[0].is_positional_only()
-        assert parameters[0].right_bracket_count == 0
-        positional_only = True
-        for p in parameters[1:]:
-            if not p.is_positional_only():
-                positional_only = False
-            else:
-                assert positional_only
-            if positional_only:
-                p.right_bracket_count = abs(p.group)
-            else:
-                # don't put any right brackets around non-positional-only parameters, ever.
-                p.right_bracket_count = 0
-
-        right_bracket_count = 0
-
-        def fix_right_bracket_count(desired: int) -> str:
-            nonlocal right_bracket_count
-            s = ''
-            while right_bracket_count < desired:
-                s += '['
-                right_bracket_count += 1
-            while right_bracket_count > desired:
-                s += ']'
-                right_bracket_count -= 1
-            return s
-
-        need_slash = False
-        added_slash = False
-        need_a_trailing_slash = False
-
-        # we only need a trailing slash:
-        #   * if this is not a "docstring_only" signature
-        #   * and if the last *shown* parameter is
-        #     positional only
-        if not f.docstring_only:
-            for p in reversed(parameters):
-                if not p.converter.show_in_signature:
-                    continue
-                if p.is_positional_only():
-                    need_a_trailing_slash = True
-                break
+        if self.forced_text_signature:
+            add(self.forced_text_signature)
+        else:
+            add('(')
+
+            # populate "right_bracket_count" field for every parameter
+            assert parameters, "We should always have a self parameter. " + repr(f)
+            assert isinstance(parameters[0].converter, self_converter)
+            # self is always positional-only.
+            assert parameters[0].is_positional_only()
+            assert parameters[0].right_bracket_count == 0
+            positional_only = True
+            for p in parameters[1:]:
+                if not p.is_positional_only():
+                    positional_only = False
+                else:
+                    assert positional_only
+                if positional_only:
+                    p.right_bracket_count = abs(p.group)
+                else:
+                    # don't put any right brackets around non-positional-only parameters, ever.
+                    p.right_bracket_count = 0
+
+            right_bracket_count = 0
+
+            def fix_right_bracket_count(desired: int) -> str:
+                nonlocal right_bracket_count
+                s = ''
+                while right_bracket_count < desired:
+                    s += '['
+                    right_bracket_count += 1
+                while right_bracket_count > desired:
+                    s += ']'
+                    right_bracket_count -= 1
+                return s
+
+            need_slash = False
+            added_slash = False
+            need_a_trailing_slash = False
+
+            # we only need a trailing slash:
+            #   * if this is not a "docstring_only" signature
+            #   * and if the last *shown* parameter is
+            #     positional only
+            if not f.docstring_only:
+                for p in reversed(parameters):
+                    if not p.converter.show_in_signature:
+                        continue
+                    if p.is_positional_only():
+                        need_a_trailing_slash = True
+                    break
 
 
-        added_star = False
+            added_star = False
 
-        first_parameter = True
-        last_p = parameters[-1]
-        line_length = len(''.join(text))
-        indent = " " * line_length
-        def add_parameter(text: str) -> None:
-            nonlocal line_length
-            nonlocal first_parameter
-            if first_parameter:
-                s = text
-                first_parameter = False
-            else:
-                s = ' ' + text
-                if line_length + len(s) >= 72:
-                    add('\n')
-                    add(indent)
-                    line_length = len(indent)
+            first_parameter = True
+            last_p = parameters[-1]
+            line_length = len(''.join(text))
+            indent = " " * line_length
+            def add_parameter(text: str) -> None:
+                nonlocal line_length
+                nonlocal first_parameter
+                if first_parameter:
                     s = text
-            line_length += len(s)
-            add(s)
-
-        for p in parameters:
-            if not p.converter.show_in_signature:
-                continue
-            assert p.name
+                    first_parameter = False
+                else:
+                    s = ' ' + text
+                    if line_length + len(s) >= 72:
+                        add('\n')
+                        add(indent)
+                        line_length = len(indent)
+                        s = text
+                line_length += len(s)
+                add(s)
+
+            for p in parameters:
+                if not p.converter.show_in_signature:
+                    continue
+                assert p.name
 
-            is_self = isinstance(p.converter, self_converter)
-            if is_self and f.docstring_only:
-                # this isn't a real machine-parsable signature,
-                # so let's not print the "self" parameter
-                continue
+                is_self = isinstance(p.converter, self_converter)
+                if is_self and f.docstring_only:
+                    # this isn't a real machine-parsable signature,
+                    # so let's not print the "self" parameter
+                    continue
 
-            if p.is_positional_only():
-                need_slash = not f.docstring_only
-            elif need_slash and not (added_slash or p.is_positional_only()):
-                added_slash = True
-                add_parameter('/,')
-
-            if p.is_keyword_only() and not added_star:
-                added_star = True
-                add_parameter('*,')
-
-            p_add, p_output = text_accumulator()
-            p_add(fix_right_bracket_count(p.right_bracket_count))
-
-            if isinstance(p.converter, self_converter):
-                # annotate first parameter as being a "self".
-                #
-                # if inspect.Signature gets this function,
-                # and it's already bound, the self parameter
-                # will be stripped off.
-                #
-                # if it's not bound, it should be marked
-                # as positional-only.
-                #
-                # note: we don't print "self" for __init__,
-                # because this isn't actually the signature
-                # for __init__.  (it can't be, __init__ doesn't
-                # have a docstring.)  if this is an __init__
-                # (or __new__), then this signature is for
-                # calling the class to construct a new instance.
-                p_add('$')
+                if p.is_positional_only():
+                    need_slash = not f.docstring_only
+                elif need_slash and not (added_slash or p.is_positional_only()):
+                    added_slash = True
+                    add_parameter('/,')
+
+                if p.is_keyword_only() and not added_star:
+                    added_star = True
+                    add_parameter('*,')
+
+                p_add, p_output = text_accumulator()
+                p_add(fix_right_bracket_count(p.right_bracket_count))
+
+                if isinstance(p.converter, self_converter):
+                    # annotate first parameter as being a "self".
+                    #
+                    # if inspect.Signature gets this function,
+                    # and it's already bound, the self parameter
+                    # will be stripped off.
+                    #
+                    # if it's not bound, it should be marked
+                    # as positional-only.
+                    #
+                    # note: we don't print "self" for __init__,
+                    # because this isn't actually the signature
+                    # for __init__.  (it can't be, __init__ doesn't
+                    # have a docstring.)  if this is an __init__
+                    # (or __new__), then this signature is for
+                    # calling the class to construct a new instance.
+                    p_add('$')
 
-            if p.is_vararg():
-                p_add("*")
+                if p.is_vararg():
+                    p_add("*")
 
-            name = p.converter.signature_name or p.name
-            p_add(name)
+                name = p.converter.signature_name or p.name
+                p_add(name)
 
-            if not p.is_vararg() and p.converter.is_optional():
-                p_add('=')
-                value = p.converter.py_default
-                if not value:
-                    value = repr(p.converter.default)
-                p_add(value)
+                if not p.is_vararg() and p.converter.is_optional():
+                    p_add('=')
+                    value = p.converter.py_default
+                    if not value:
+                        value = repr(p.converter.default)
+                    p_add(value)
 
-            if (p != last_p) or need_a_trailing_slash:
-                p_add(',')
+                if (p != last_p) or need_a_trailing_slash:
+                    p_add(',')
 
-            add_parameter(p_output())
+                add_parameter(p_output())
 
-        add(fix_right_bracket_count(0))
-        if need_a_trailing_slash:
-            add_parameter('/')
-        add(')')
+            add(fix_right_bracket_count(0))
+            if need_a_trailing_slash:
+                add_parameter('/')
+            add(')')
 
         # PEP 8 says:
         #