@@ -182,19 +182,12 @@ def get_argspec(ob):
         # If fob has no argument, use default callable argspec.
         argspec = _default_callable_argspec
 
-    lines = (textwrap.wrap(argspec, _MAX_COLS, subsequent_indent=_INDENT)
-             if len(argspec) > _MAX_COLS else [argspec] if argspec else [])
+    lines = [argspec] if argspec else []
 
     # Augment lines from docstring, if any, and join to get argspec.
     doc = inspect.getdoc(ob)
     if doc:
-        for line in doc.split('\n', _MAX_LINES)[:_MAX_LINES]:
-            line = line.strip()
-            if not line:
-                break
-            if len(line) > _MAX_COLS:
-                line = line[: _MAX_COLS - 3] + '...'
-            lines.append(line)
+        lines.extend(map(str.strip, doc.split('\n')))
     argspec = '\n'.join(lines)
 
     return argspec or _default_callable_argspec

@@ -4,18 +4,26 @@
 Used by calltip.py.
 """
 from tkinter import Label, LEFT, SOLID, TclError
+from tkinter.scrolledtext import ScrolledText
 
 from idlelib.tooltip import TooltipBase
 
 HIDE_EVENT = "<<calltipwindow-hide>>"
-HIDE_SEQUENCES = ("<Key-Escape>", "<FocusOut>")
+HIDE_SEQUENCES = ("<Key-Escape>",)
 CHECKHIDE_EVENT = "<<calltipwindow-checkhide>>"
 CHECKHIDE_SEQUENCES = ("<KeyRelease>", "<ButtonRelease>")
 CHECKHIDE_TIME = 100  # milliseconds
 
 MARK_RIGHT = "calltipwindowregion_right"
 
 
+def _widget_size(widget):
+    widget.update()
+    width = widget.winfo_width()
+    height = widget.winfo_height()
+    return width, height
+
+
 class CalltipWindow(TooltipBase):
     """A call-tip widget for tkinter text widgets."""
 
@@ -74,16 +82,31 @@ def showtip(self, text, parenleft, parenright):
             int, self.anchor_widget.index(parenleft).split("."))
 
         super().showtip()
+        self.tipwindow.wm_attributes("-topmost", 1)
 
         self._bind_events()
 
     def showcontents(self):
         """Create the call-tip widget."""
-        self.label = Label(self.tipwindow, text=self.text, justify=LEFT,
+        self.label = Label(self.tipwindow, text=self.text, font=self.anchor_widget['font'])
+        self.label.pack()
+        old_w, old_h = _widget_size(self.label)
+        self.label.forget()
+
+        self.label = ScrolledText(self.tipwindow, wrap="word",
                            background="#ffffd0", foreground="black",
                            relief=SOLID, borderwidth=1,
                            font=self.anchor_widget['font'])
+        self.label.insert("1.0", self.text)
+        self.label.config(state="disabled")
         self.label.pack()
+        new_w, new_h = _widget_size(self.label)
+
+        if self.label.yview()[1] == 1:  # already shown entire text
+            self.label.vbar.forget()
+
+        w, h = min(old_w, new_w), min(old_h, new_h)
+        self.tipwindow.geometry("%dx%d" % (w, h))
 
     def checkhide_event(self, event=None):
         """Handle CHECK_HIDE_EVENT: call hidetip or reschedule."""
@@ -156,6 +179,8 @@ def _bind_events(self):
                                               self.hide_event)
         for seq in HIDE_SEQUENCES:
             self.anchor_widget.event_add(HIDE_EVENT, seq)
+        if self.tipwindow:
+            self.tipwindow.bind("<Key-Escape>", self.hide_event)
 
     def _unbind_events(self):
         """Unbind event handlers."""

@@ -93,19 +93,20 @@ class SB:  __call__ = None
 non-overlapping occurrences of the pattern in string by the
 replacement repl.  repl can be either a string or a callable;
 if a string, backslash escapes in it are processed.  If it is
-a callable, it's passed the Match object and must return''')
+a callable, it's passed the Match object and must return
+a replacement string to be used.''')
         tiptest(p.sub, '''\
 (repl, string, count=0)
 Return the string obtained by replacing the leftmost \
-non-overlapping occurrences o...''')
+non-overlapping occurrences of pattern in string by the replacement repl.''')
 
     def test_signature_wrap(self):
         if textwrap.TextWrapper.__doc__ is not None:
-            self.assertEqual(get_spec(textwrap.TextWrapper), '''\
-(width=70, initial_indent='', subsequent_indent='', expand_tabs=True,
-    replace_whitespace=True, fix_sentence_endings=False, break_long_words=True,
-    drop_whitespace=True, break_on_hyphens=True, tabsize=8, *, max_lines=None,
-    placeholder=' [...]')
+            self.assertEqual(get_spec(textwrap.TextWrapper).split('\n\n')[0], '''\
+(width=70, initial_indent='', subsequent_indent='', expand_tabs=True, \
+replace_whitespace=True, fix_sentence_endings=False, break_long_words=True, \
+drop_whitespace=True, break_on_hyphens=True, tabsize=8, *, max_lines=None, \
+placeholder=' [...]')
 Object for wrapping/filling text.  The public interface consists of
 the wrap() and fill() methods; the other methods are just there for
 subclasses to override in order to tweak the default behaviour.
@@ -124,19 +125,15 @@ def bar(s='a'*100):
         def baz(s='a'*100, z='b'*100):
             pass
 
-        indent = calltip._INDENT
-
         sfoo = "(s='aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"\
-               "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n" + indent + "aaaaaaaaa"\
-               "aaaaaaaaaa')"
+               "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa')"
         sbar = "(s='aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"\
-               "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n" + indent + "aaaaaaaaa"\
-               "aaaaaaaaaa')\nHello Guido"
+               "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa')"\
+               "\nHello Guido"
         sbaz = "(s='aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"\
-               "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\n" + indent + "aaaaaaaaa"\
-               "aaaaaaaaaa', z='bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"\
-               "bbbbbbbbbbbbbbbbb\n" + indent + "bbbbbbbbbbbbbbbbbbbbbb"\
-               "bbbbbbbbbbbbbbbbbbbbbb')"
+               "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa',"\
+               " z='bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb"\
+               "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb')"
 
         for func,doc in [(foo, sfoo), (bar, sbar), (baz, sbaz)]:
             with self.subTest(func=func, doc=doc):
@@ -145,29 +142,41 @@ def baz(s='a'*100, z='b'*100):
     def test_docline_truncation(self):
         def f(): pass
         f.__doc__ = 'a'*300
-        self.assertEqual(get_spec(f), f"()\n{'a'*(calltip._MAX_COLS-3) + '...'}")
+        self.assertEqual(get_spec(f), f"()\n{f.__doc__}")
 
     @unittest.skipIf(MISSING_C_DOCSTRINGS,
                      "Signature information for builtins requires docstrings")
     def test_multiline_docstring(self):
         # Test fewer lines than max.
-        self.assertEqual(get_spec(range),
-                "range(stop) -> range object\n"
-                "range(start, stop[, step]) -> range object")
+        self.assertEqual(get_spec(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(i, j) produces i, i+1, i+2, ..., j-1.
+start defaults to 0, and stop is omitted!  range(4) produces 0, 1, 2, 3.
+These are exactly the valid indices for a list of 4 elements.
+When step is given, it specifies the increment (or decrement).''')
 
         # Test max lines
         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''')
+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''')
 
     def test_multiline_docstring_2(self):
         # Test more than max lines
         def f(): pass
         f.__doc__ = 'a\n' * 15
-        self.assertEqual(get_spec(f), '()' + '\na' * calltip._MAX_LINES)
+        self.assertEqual(get_spec(f), '()\n' + f.__doc__[:-1])
 
     def test_functions(self):
         def t1(): 'doc'

diff --git a/Misc/NEWS.d/next/IDLE/2025-12-21-07-02-44.gh-issue-94520.lqenne.rst b/Misc/NEWS.d/next/IDLE/2025-12-21-07-02-44.gh-issue-94520.lqenne.rst
@@ -0,0 +1,3 @@
+"Calltip" windows now support text selection, scrolling and
+avoid truncating their content (in particular, docstrings
+are shown in full). Patch by Shixian Li.