feat: Add an inprocess backend to pymapdl (#3198)

* add an inprocess backend to pymapdl

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: pyansys-ci-bot <pyansys.github.bot@ansys.com>

doc/changelog.d/3198.added.md

@@ -0,0 +1 @@
+feat: Add an inprocess backend to pymapdl

pyproject.toml

@@ -150,6 +150,8 @@ omit = [
     # ignore legacy interfaces
     "ansys/mapdl/core/mapdl_console.py",
     "ansys/mapdl/core/jupyter.py",
+    # ignore non exposed interfaces
+    "ansys/mapdl/core/mapdl_inprocess.py",
 ]
 
 [tool.coverage.report]

src/ansys/mapdl/core/mapdl_inprocess.py

@@ -0,0 +1,65 @@
+# Copyright (C) 2024 ANSYS, Inc. and/or its affiliates.
+# SPDX-License-Identifier: MIT
+#
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+from typing import Optional, Protocol
+
+from ansys.mapdl.core.mapdl import MapdlBase
+
+
+class _Backend(Protocol):
+    def run_command(self) -> str: ...
+
+
+class MapdlInProcess(MapdlBase):
+    def __init__(self, backend: _Backend):
+        super().__init__(
+            loglevel="WARNING", use_vtk=False, log_apdl=None, print_com=False
+        )
+        self._backend = backend
+        self._cleanup: bool = True
+        self._name: str = "MapdlInProcess"
+        self._session_id: Optional[str] = None
+        self._mute: bool = False
+
+    def _run(self, command: str, verbose: bool = False, mute: bool = False) -> str:
+        if not command.strip():
+            raise ValueError("Empty commands not allowed")
+
+        if len(command) > 639:
+            raise ValueError("Maximum command length mut be less than 640 characters")
+
+        return self._backend.run_command(command, verbose, mute).strip()
+
+    @property
+    def name(self) -> str:
+        return self._name
+
+    @name.setter
+    def name(self, name) -> None:
+        self._name = name
+
+    def _check_session_id(self) -> None:
+        pass
+
+    def __repr__(self):
+        info = super().__repr__()
+        return info