gh-73536: Add support for multi-signatures

Lib/dataclasses.py

@@ -1162,10 +1162,11 @@ def _process_class(cls, init, repr, eq, order, unsafe_hash, frozen,
         try:
             # In some cases fetching a signature is not possible.
             # But, we surely should not fail in this case.
-            text_sig = str(inspect.signature(cls)).replace(' -> None', '')
+            doc = '\n'.join(cls.__name__ + str(sig).replace(' -> None', '')
+                            for sig in inspect.signatures(cls))
         except (TypeError, ValueError):
-            text_sig = ''
-        cls.__doc__ = (cls.__name__ + text_sig)
+            doc = cls.__name__
+        cls.__doc__ = doc
 
     if match_args:
         # I could probably compute this once.

Lib/idlelib/calltip.py

@@ -170,20 +170,25 @@ def get_argspec(ob):
 
     # Initialize argspec and wrap it to get lines.
     try:
-        argspec = str(inspect.signature(fob))
+        signatures = inspect.signatures(fob)
     except Exception as err:
         msg = str(err)
         if msg.startswith(_invalid_method):
             return _invalid_method
         else:
-            argspec = ''
+            signatures = []
 
-    if isinstance(fob, type) and argspec == '()':
+    lines = []
+    for sig in signatures:
+        line = str(sig)
+        if len(line) > _MAX_COLS:
+            lines.extend(textwrap.wrap(line, _MAX_COLS, subsequent_indent=_INDENT))
+        else:
+            lines.append(line)
+    if isinstance(fob, type) and lines == ['()']:
         # If fob has no argument, use default callable argspec.
-        argspec = _default_callable_argspec
+        lines = [_default_callable_argspec]
 
-    lines = (textwrap.wrap(argspec, _MAX_COLS, subsequent_indent=_INDENT)
-             if len(argspec) > _MAX_COLS else [argspec] if argspec else [])
 
     # Augment lines from docstring, if any, and join to get argspec.
     doc = inspect.getdoc(ob)

Lib/idlelib/idle_test/test_calltip.py

@@ -3,6 +3,7 @@
 from idlelib import calltip
 import unittest
 from unittest.mock import Mock
+import builtins
 import textwrap
 import types
 import re
@@ -151,17 +152,48 @@ def f(): pass
                      "Signature information for builtins requires docstrings")
     def test_multiline_docstring(self):
         # Test fewer lines than max.
+        def range():
+            """range(stop) -> range object
+            range(start, stop[, step]) -> range object
+
+            Return an object that produces a sequence of integers from start
+            (inclusive) to stop (exclusive) by step.
+            """
+        range.__text_signature__ = '<no signature>'
         self.assertEqual(get_spec(range),
                 "range(stop) -> range object\n"
                 "range(start, stop[, step]) -> range object")
+        self.assertEqual(get_spec(builtins.range),
+                "(stop, /)\n"
+                "(start, stop, step=1, /)\n"
+                "Create a range object.")
 
         # Test max lines
+        def bytes():
+            """bytes(iterable_of_ints) -> bytes
+            bytes(string, encoding[, errors]) -> bytes
+            bytes(bytes_or_buffer) -> immutable copy of bytes_or_buffer
+            bytes(int) -> bytes object of size given by the parameter initialized with null bytes
+            bytes() -> empty bytes object
+
+            Construct an immutable array of bytes from:
+              - an iterable yielding integers in range(256)
+              - a text string encoded using the specified encoding
+              - any object implementing the buffer API.
+              - an integer"""
+        bytes.__text_signature__ = '<no signature>'
         self.assertEqual(get_spec(bytes), '''\
 bytes(iterable_of_ints) -> bytes
 bytes(string, encoding[, errors]) -> bytes
 bytes(bytes_or_buffer) -> immutable copy of bytes_or_buffer
 bytes(int) -> bytes object of size given by the parameter initialized with null bytes
 bytes() -> empty bytes object''')
+        self.assertEqual(get_spec(builtins.bytes), '''\
+()
+(source)
+(source, encoding)
+(source, encoding, errors)
+Construct an immutable array of bytes.''')
 
     def test_multiline_docstring_2(self):
         # Test more than max lines