示例#1
0
        /// <summary>
        /// When called after SetError, sets the cause of the error.
        /// </summary>
        /// <param name="cause">The cause of the current error</param>
        public static void SetCause(PythonException cause)
        {
            var currentException = new PythonException();

            currentException.Normalize();
            cause.Normalize();
            Runtime.XIncref(cause.PyValue);
            Runtime.PyException_SetCause(currentException.PyValue, cause.PyValue);
            currentException.Restore();
        }
示例#2
0
        /// <summary>
        /// The actual import hook that ties Python to the managed world.
        /// </summary>
        public static IntPtr __import__(IntPtr self, IntPtr argsRaw, IntPtr kw)
        {
            var args = new BorrowedReference(argsRaw);

            // Replacement for the builtin __import__. The original import
            // hook is saved as this.py_import. This version handles CLR
            // import and defers to the normal builtin for everything else.

            var num_args = Runtime.PyTuple_Size(args);

            if (num_args < 1)
            {
                return(Exceptions.RaiseTypeError("__import__() takes at least 1 argument (0 given)"));
            }

            BorrowedReference py_mod_name = Runtime.PyTuple_GetItem(args, 0);

            if (py_mod_name.IsNull ||
                !Runtime.IsStringType(py_mod_name))
            {
                return(Exceptions.RaiseTypeError("string expected"));
            }

            // Check whether the import is of the form 'from x import y'.
            // This determines whether we return the head or tail module.

            BorrowedReference fromList = default;
            var fromlist = false;

            if (num_args >= 4)
            {
                fromList = Runtime.PyTuple_GetItem(args, 3);
                if (fromList != null &&
                    Runtime.PyObject_IsTrue(fromList) == 1)
                {
                    fromlist = true;
                }
            }

            string mod_name = Runtime.GetManagedString(py_mod_name);

            // Check these BEFORE the built-in import runs; may as well
            // do the Incref()ed return here, since we've already found
            // the module.
            if (mod_name == "clr")
            {
                NewReference clr_module = GetCLRModule(fromList);
                if (!clr_module.IsNull())
                {
                    BorrowedReference sys_modules = Runtime.PyImport_GetModuleDict();
                    if (!sys_modules.IsNull)
                    {
                        Runtime.PyDict_SetItemString(sys_modules, "clr", clr_module);
                    }
                }
                return(clr_module.DangerousMoveToPointerOrNull());
            }

            string realname = mod_name;

            // 2010-08-15: Always seemed smart to let python try first...
            // This shaves off a few tenths of a second on test_module.py
            // and works around a quirk where 'sys' is found by the
            // LoadImplicit() deprecation logic.
            // Turns out that the AssemblyManager.ResolveHandler() checks to see if any
            // Assembly's FullName.ToLower().StartsWith(name.ToLower()), which makes very
            // little sense to me.
            IntPtr res = Runtime.PyObject_Call(py_import, args.DangerousGetAddress(), kw);

            if (res != IntPtr.Zero)
            {
                // There was no error.
                if (fromlist && IsLoadAll(fromList))
                {
                    var mod = ManagedType.GetManagedObject(res) as ModuleObject;
                    mod?.LoadNames();
                }
                return(res);
            }
            // There was an error
            if (!Exceptions.ExceptionMatches(Exceptions.ImportError))
            {
                // and it was NOT an ImportError; bail out here.
                return(IntPtr.Zero);
            }

            if (mod_name == string.Empty)
            {
                // Most likely a missing relative import.
                // For example site-packages\bs4\builder\__init__.py uses it to check if a package exists:
                //     from . import _html5lib
                // We don't support them anyway
                return(IntPtr.Zero);
            }
            // Save the exception
            var originalException = new PythonException();

            // Otherwise,  just clear the it.
            Exceptions.Clear();

            string[] names = realname.Split('.');

            // See if sys.modules for this interpreter already has the
            // requested module. If so, just return the existing module.
            BorrowedReference modules = Runtime.PyImport_GetModuleDict();
            BorrowedReference module  = Runtime.PyDict_GetItem(modules, py_mod_name);

            if (module != null)
            {
                if (fromlist)
                {
                    if (IsLoadAll(fromList))
                    {
                        var mod = ManagedType.GetManagedObject(module) as ModuleObject;
                        mod?.LoadNames();
                    }
                    return(new NewReference(module).DangerousMoveToPointer());
                }

                module = Runtime.PyDict_GetItemString(modules, names[0]);
                return(new NewReference(module, canBeNull: true).DangerousMoveToPointer());
            }
            Exceptions.Clear();

            // Traverse the qualified module name to get the named module
            // and place references in sys.modules as we go. Note that if
            // we are running in interactive mode we pre-load the names in
            // each module, which is often useful for introspection. If we
            // are not interactive, we stick to just-in-time creation of
            // objects at lookup time, which is much more efficient.
            // NEW: The clr got a new module variable preload. You can
            // enable preloading in a non-interactive python processing by
            // setting clr.preload = True

            ModuleObject head = mod_name == realname ? null : root;
            ModuleObject tail = root;

            root.InitializePreload();

            foreach (string name in names)
            {
                ManagedType mt = tail.GetAttribute(name, true);
                if (!(mt is ModuleObject))
                {
                    originalException.Restore();
                    return(IntPtr.Zero);
                }
                if (head == null)
                {
                    head = (ModuleObject)mt;
                }
                tail = (ModuleObject)mt;
                if (CLRModule.preload)
                {
                    tail.LoadNames();
                }

                // Add the module to sys.modules
                Runtime.PyDict_SetItemString(modules, tail.moduleName, tail.ObjectReference);
            }

            {
                var mod = fromlist ? tail : head;

                if (fromlist && IsLoadAll(fromList))
                {
                    mod.LoadNames();
                }

                Runtime.XIncref(mod.pyHandle);
                return(mod.pyHandle);
            }
        }