Refactor GIL usage in Python execution and error handling

Moved _withGIL calls to wrap larger code blocks instead of individual function calls in runPythonProgramInIsolate and getPythonError. This simplifies the code and reduces redundant GIL management, improving readability and maintainability.

Author: FeodorFitsner

src/serious_python_android/lib/src/cpython.dart

@@ -96,17 +96,14 @@ Future<String> runPythonProgramInIsolate(List<Object> arguments) async {
     _debug("after Py_Initialize()");
   }
 
-  final logcatSetupError = _withGIL(cpython, () => _setupLogcatForwarding(cpython));
-  if (logcatSetupError != null) {
-    sendPort.send(logcatSetupError);
-    return logcatSetupError;
-  }
-
-  var result = "";
+  final result = _withGIL(cpython, () {
+    final logcatSetupError = _setupLogcatForwarding(cpython);
+    if (logcatSetupError != null) {
+      return logcatSetupError;
+    }
 
-  if (script != "") {
-    // run script
-    result = _withGIL(cpython, () {
+    if (script != "") {
+      // run script
       _debug("Running script: $script");
       final scriptPtr = script.toNativeUtf8();
       int sr = cpython.PyRun_SimpleString(scriptPtr.cast<Char>());
@@ -115,11 +112,8 @@ Future<String> runPythonProgramInIsolate(List<Object> arguments) async {
       if (sr != 0) {
         return getPythonError(cpython);
       }
-      return "";
-    });
-  } else {
-    // run program
-    result = _withGIL(cpython, () {
+    } else {
+      // run program
       _debug("Running program module: $programModuleName");
       final moduleNamePtr = programModuleName.toNativeUtf8();
       var modulePtr = cpython.PyImport_ImportModule(moduleNamePtr.cast<Char>());
@@ -129,9 +123,10 @@ Future<String> runPythonProgramInIsolate(List<Object> arguments) async {
         return error;
       }
       malloc.free(moduleNamePtr);
-      return "";
-    });
-  }
+    }
+
+    return "";
+  });
 
   _debug("Python program finished");
 
@@ -142,41 +137,38 @@ Future<String> runPythonProgramInIsolate(List<Object> arguments) async {
 
 String getPythonError(CPython cpython) {
   // get error object
-  var exPtr = _withGIL(cpython, () => cpython.PyErr_GetRaisedException());
+  var exPtr = cpython.PyErr_GetRaisedException();
 
   // use 'traceback' module to format exception
   final tracebackModuleNamePtr = "traceback".toNativeUtf8();
-  var tracebackModulePtr = _withGIL(cpython,
-      () => cpython.PyImport_ImportModule(tracebackModuleNamePtr.cast<Char>()));
+  var tracebackModulePtr =
+      cpython.PyImport_ImportModule(tracebackModuleNamePtr.cast<Char>());
   cpython.Py_DecRef(tracebackModuleNamePtr.cast());
 
   if (tracebackModulePtr != nullptr) {
     //_debug("Traceback module loaded");
 
     final formatFuncName = "format_exception".toNativeUtf8();
-    final pFormatFunc = _withGIL(
-        cpython,
-        () => cpython.PyObject_GetAttrString(
-            tracebackModulePtr, formatFuncName.cast()));
+    final pFormatFunc =
+        cpython.PyObject_GetAttrString(tracebackModulePtr, formatFuncName.cast());
     cpython.Py_DecRef(tracebackModuleNamePtr.cast());
 
     if (pFormatFunc != nullptr && cpython.PyCallable_Check(pFormatFunc) != 0) {
       // call `traceback.format_exception()` method
-      final pArgs = _withGIL(cpython, () => cpython.PyTuple_New(1));
-      _withGIL(cpython, () => cpython.PyTuple_SetItem(pArgs, 0, exPtr));
+      final pArgs = cpython.PyTuple_New(1);
+      cpython.PyTuple_SetItem(pArgs, 0, exPtr);
 
       // result is a list
-      var listPtr =
-          _withGIL(cpython, () => cpython.PyObject_CallObject(pFormatFunc, pArgs));
+      var listPtr = cpython.PyObject_CallObject(pFormatFunc, pArgs);
 
       // get and combine list items
       var exLines = [];
-      var listSize = _withGIL(cpython, () => cpython.PyList_Size(listPtr));
+      var listSize = cpython.PyList_Size(listPtr);
       for (var i = 0; i < listSize; i++) {
-        var itemObj = _withGIL(cpython, () => cpython.PyList_GetItem(listPtr, i));
-        var itemObjStr = _withGIL(cpython, () => cpython.PyObject_Str(itemObj));
-        var s = _withGIL(cpython,
-            () => cpython.PyUnicode_AsUTF8(itemObjStr).cast<Utf8>().toDartString());
+        var itemObj = cpython.PyList_GetItem(listPtr, i);
+        var itemObjStr = cpython.PyObject_Str(itemObj);
+        var s =
+            cpython.PyUnicode_AsUTF8(itemObjStr).cast<Utf8>().toDartString();
         exLines.add(s);
       }
       return exLines.join("");