gh-92345: Import rlcompleter before sys.path is extended (#92346)

tiran · web-flow · commit 8122e8d5017b · 2022-05-05T21:24:16.000+02:00
``pymain_run_python()`` now imports ``readline`` and ``rlcompleter``
before sys.path is extended to include the current working directory of
an interactive interpreter. Non-interactive interpreters are not
affected.

Also move imports of ``re`` and ``keyword`` module to top level so they
are materialized early, too. The ``keyword`` module is trivial and the
``re`` is already imported via ``inspect`` -&gt; ``linecache``.
diff --git a/Lib/rlcompleter.py b/Lib/rlcompleter.py
@@ -32,6 +32,8 @@
 import atexit
 import builtins
 import inspect
+import keyword
+import re
 import __main__
 
 __all__ = ["Completer"]
@@ -113,7 +115,6 @@ def global_matches(self, text):
         defined in self.namespace that match.
 
         """
-        import keyword
         matches = []
         seen = {"__builtins__"}
         n = len(text)
@@ -146,7 +147,6 @@ def attr_matches(self, text):
         with a __getattr__ hook is evaluated.
 
         """
-        import re
         m = re.match(r"(\w+(\.\w+)*)\.(\w*)", text)
         if not m:
             return []
diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-05-05-20-05-41.gh-issue-92345.lnN_RA.rst b/Misc/NEWS.d/next/Core and Builtins/2022-05-05-20-05-41.gh-issue-92345.lnN_RA.rst
@@ -0,0 +1,3 @@
+``pymain_run_python()`` now imports ``readline`` and ``rlcompleter`` before
+sys.path is extended to include the current working directory of an
+interactive interpreter. Non-interactive interpreters are not affected.
diff --git a/Modules/main.c b/Modules/main.c
@@ -219,6 +219,13 @@ pymain_import_readline(const PyConfig *config)
     else {
         Py_DECREF(mod);
     }
+    mod = PyImport_ImportModule("rlcompleter");
+    if (mod == NULL) {
+        PyErr_Clear();
+    }
+    else {
+        Py_DECREF(mod);
+    }
 }
 
 
@@ -555,6 +562,9 @@ pymain_run_python(int *exitcode)
         }
     }
 
+    // import readline and rlcompleter before script dir is added to sys.path
+    pymain_import_readline(config);
+
     if (main_importer_path != NULL) {
         if (pymain_sys_path_add_path0(interp, main_importer_path) < 0) {
             goto error;
@@ -577,7 +587,6 @@ pymain_run_python(int *exitcode)
     }
 
     pymain_header(config);
-    pymain_import_readline(config);
 
     if (config->run_command) {
         *exitcode = pymain_run_command(config->run_command);

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	+``pymain_run_python()`` now imports ``readline`` and ``rlcompleter`` before
	`2`	`+sys.path is extended to include the current working directory of an`
	`3`	`+interactive interpreter. Non-interactive interpreters are not affected.`
Original file line number	Diff line number	Diff line change
`@@ -219,6 +219,13 @@ pymain_import_readline(const PyConfig *config)`
`219`	`219`	`else {`
`220`	`220`	`Py_DECREF(mod);`
`221`	`221`	`}`
	`222`	`+ mod = PyImport_ImportModule("rlcompleter");`
	`223`	`+ if (mod == NULL) {`
	`224`	`+ PyErr_Clear();`
	`225`	`+ }`
	`226`	`+ else {`
	`227`	`+ Py_DECREF(mod);`
	`228`	`+ }`
`222`	`229`	`}`
`223`	`230`
`224`	`231`
`@@ -555,6 +562,9 @@ pymain_run_python(int *exitcode)`
`555`	`562`	`}`
`556`	`563`	`}`
`557`	`564`
	`565`	`+ // import readline and rlcompleter before script dir is added to sys.path`
	`566`	`+ pymain_import_readline(config);`
	`567`	`+`
`558`	`568`	`if (main_importer_path != NULL) {`
`559`	`569`	`if (pymain_sys_path_add_path0(interp, main_importer_path) < 0) {`
`560`	`570`	`goto error;`
`@@ -577,7 +587,6 @@ pymain_run_python(int *exitcode)`
`577`	`587`	`}`
`578`	`588`
`579`	`589`	`pymain_header(config);`
`580`		`- pymain_import_readline(config);`
`581`	`590`
`582`	`591`	`if (config->run_command) {`
`583`	`592`	`*exitcode = pymain_run_command(config->run_command);`