gh-108308: Replace _PyDict_GetItemStringWithError() (#108372)

Replace _PyDict_GetItemStringWithError() calls with
PyDict_GetItemStringRef() which returns a strong reference to the
item.

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

3 files changed, 22 insertions, 24 deletions

diff --git a/Python/codecs.c b/Python/codecs.c
index 3c41851..87ae896 100644
--- a/Python/codecs.c
+++ b/Python/codecs.c
@@ -10,7 +10,6 @@ Copyright (c) Corporation for National Research Initiatives.
 
 #include "Python.h"
 #include "pycore_call.h"          // _PyObject_CallNoArgs()
-#include "pycore_dict.h"          // _PyDict_GetItemStringWithError()
 #include "pycore_interp.h"        // PyInterpreterState.codec_search_path
 #include "pycore_pyerrors.h"      // _PyErr_FormatNote()
 #include "pycore_pystate.h"       // _PyInterpreterState_GET()
@@ -618,20 +617,19 @@ int PyCodec_RegisterError(const char *name, PyObject *error)
    the error handling callback for strict encoding will be returned. */
 PyObject *PyCodec_LookupError(const char *name)
 {
-    PyObject *handler = NULL;
-
     PyInterpreterState *interp = _PyInterpreterState_GET();
     if (interp->codec_search_path == NULL && _PyCodecRegistry_Init())
         return NULL;
 
     if (name==NULL)
         name = "strict";
-    handler = _PyDict_GetItemStringWithError(interp->codec_error_registry, name);
-    if (handler) {
-        Py_INCREF(handler);
+    PyObject *handler;
+    if (PyDict_GetItemStringRef(interp->codec_error_registry, name, &handler) < 0) {
+        return NULL;
     }
-    else if (!PyErr_Occurred()) {
+    if (handler == NULL) {
         PyErr_Format(PyExc_LookupError, "unknown error handler name '%.400s'", name);
+        return NULL;
     }
     return handler;
 }
diff --git a/Python/import.c b/Python/import.c
index 4abb2f6..5681deb 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -1,7 +1,6 @@
 /* Module definition and import implementation */
 
 #include "Python.h"
-#include "pycore_dict.h"          // _PyDict_GetItemStringWithError()
 #include "pycore_hashtable.h"     // _Py_hashtable_new_full()
 #include "pycore_import.h"        // _PyImport_BootstrapImp()
 #include "pycore_initconfig.h"    // _PyStatus_OK()
@@ -2435,12 +2434,11 @@ int
 _PyImport_InitDefaultImportFunc(PyInterpreterState *interp)
 {
     // Get the __import__ function
-    PyObject *import_func = _PyDict_GetItemStringWithError(interp->builtins,
-                                                           "__import__");
-    if (import_func == NULL) {
+    PyObject *import_func;
+    if (PyDict_GetItemStringRef(interp->builtins, "__import__", &import_func) <= 0) {
         return -1;
     }
-    IMPORT_FUNC(interp) = Py_NewRef(import_func);
+    IMPORT_FUNC(interp) = import_func;
     return 0;
 }
 
diff --git a/Python/pylifecycle.c b/Python/pylifecycle.c
index 8c321fb..1861426 100644
--- a/Python/pylifecycle.c
+++ b/Python/pylifecycle.c
@@ -1372,17 +1372,17 @@ finalize_modules_delete_special(PyThreadState *tstate, int verbose)
         if (verbose) {
             PySys_WriteStderr("# restore sys.%s\n", name);
         }
-        PyObject *value = _PyDict_GetItemStringWithError(interp->sysdict,
-                                                         orig_name);
+        PyObject *value;
+        if (PyDict_GetItemStringRef(interp->sysdict, orig_name, &value) < 0) {
+            PyErr_WriteUnraisable(NULL);
+        }
         if (value == NULL) {
-            if (_PyErr_Occurred(tstate)) {
-                PyErr_WriteUnraisable(NULL);
-            }
-            value = Py_None;
+            value = Py_NewRef(Py_None);
         }
         if (PyDict_SetItemString(interp->sysdict, name, value) < 0) {
             PyErr_WriteUnraisable(NULL);
         }
+        Py_DECREF(value);
     }
 }
 
@@ -2207,7 +2207,7 @@ _Py_IsInterpreterFinalizing(PyInterpreterState *interp)
 static PyStatus
 add_main_module(PyInterpreterState *interp)
 {
-    PyObject *m, *d, *loader, *ann_dict;
+    PyObject *m, *d, *ann_dict;
     m = PyImport_AddModule("__main__");
     if (m == NULL)
         return _PyStatus_ERR("can't create __main__ module");
@@ -2239,11 +2239,13 @@ add_main_module(PyInterpreterState *interp)
      * will be set if __main__ gets further initialized later in the startup
      * process.
      */
-    loader = _PyDict_GetItemStringWithError(d, "__loader__");
-    if (loader == NULL || loader == Py_None) {
-        if (PyErr_Occurred()) {
-            return _PyStatus_ERR("Failed to test __main__.__loader__");
-        }
+    PyObject *loader;
+    if (PyDict_GetItemStringRef(d, "__loader__", &loader) < 0) {
+        return _PyStatus_ERR("Failed to test __main__.__loader__");
+    }
+    int has_loader = !(loader == NULL || loader == Py_None);
+    Py_XDECREF(loader);
+    if (!has_loader) {
         PyObject *loader = _PyImport_GetImportlibLoader(interp,
                                                         "BuiltinImporter");
         if (loader == NULL) {