gh-102541: Hide traceback in help prompt

Author: Eclips4

Lib/pydoc.py

@@ -78,6 +78,10 @@ class or function within a module or module in a package.  If the
 
 
 # --------------------------------------------------------- common routines
+missing_pattern = '''\
+No Python documentation found for %r.
+Use help() to get the interactive help utility.
+Use help(str) for help on the str class.'''
 
 def pathdirs():
     """Convert sys.path into a list of absolute, existing, unique paths."""
@@ -1738,10 +1742,7 @@ def resolve(thing, forceload=0):
     if isinstance(thing, str):
         object = locate(thing, forceload)
         if object is None:
-            raise ImportError('''\
-No Python documentation found for %r.
-Use help() to get the interactive help utility.
-Use help(str) for help on the str class.''' % thing)
+            raise ImportError(missing_pattern % thing)
         return object, thing
     else:
         name = getattr(thing, '__name__', None)
@@ -1775,10 +1776,15 @@ def render_doc(thing, title='Python Library Documentation: %s', forceload=0,
     return title % desc + '\n\n' + renderer.document(object, name)
 
 def doc(thing, title='Python Library Documentation: %s', forceload=0,
-        output=None):
+        output=None, is_cli=False):
     """Display text documentation, given an object or a path to an object."""
     if output is None:
-        pager(render_doc(thing, title, forceload))
+        try:
+            pager(render_doc(thing, title, forceload))
+        except ImportError:
+            if is_cli:
+                raise ImportError(missing_pattern % thing) from None
+            pager(missing_pattern % thing)
     else:
         output.write(render_doc(thing, title, forceload, plaintext))
 
@@ -2039,7 +2045,7 @@ def getline(self, prompt):
             self.output.flush()
             return self.input.readline()
 
-    def help(self, request):
+    def help(self, request, is_cli=False):
         if isinstance(request, str):
             request = request.strip()
             if request == 'keywords': self.listkeywords()
@@ -2051,13 +2057,13 @@ def help(self, request):
             elif request in self.symbols: self.showsymbol(request)
             elif request in ['True', 'False', 'None']:
                 # special case these keywords since they are objects too
-                doc(eval(request), 'Help on %s:')
+                doc(eval(request), 'Help on %s:', is_cli=is_cli)
             elif request in self.keywords: self.showtopic(request)
             elif request in self.topics: self.showtopic(request)
-            elif request: doc(request, 'Help on %s:', output=self._output)
-            else: doc(str, 'Help on %s:', output=self._output)
+            elif request: doc(request, 'Help on %s:', output=self._output, is_cli=is_cli)
+            else: doc(str, 'Help on %s:', output=self._output, is_cli=is_cli)
         elif isinstance(request, Helper): self()
-        else: doc(request, 'Help on %s:', output=self._output)
+        else: doc(request, 'Help on %s:', output=self._output, is_cli=is_cli)
         self.output.write('\n')
 
     def intro(self):
@@ -2751,7 +2757,6 @@ def cli():
     """Command-line interface (looks at sys.argv to decide what to do)."""
     import getopt
     class BadUsage(Exception): pass
-
     _adjust_cli_sys_path()
 
     try:
@@ -2795,7 +2800,7 @@ class BadUsage(Exception): pass
                     else:
                         writedoc(arg)
                 else:
-                    help.help(arg)
+                    help.help(arg, is_cli=True)
             except (ImportError, ErrorDuringImport) as value:
                 print(value)
                 sys.exit(1)

Misc/NEWS.d/next/Library/2023-03-12-01-17-15.gh-issue-102541.LK1adc.rst

@@ -0,0 +1 @@
+Hide traceback in ``help`` prompt, when import failed.