Run gdb stubtests (#11644)

The gdb package is only available inside gdb and cannot be installed externally through e.g. pip.
Run the stubtest inside gdb.

stubs/gdb/@tests/stubtest_allowlist.txt

@@ -0,0 +1,119 @@
+# TODO: Update types in stub
+# This list includes everything to allow initial stubtests to run in gdb's environment
+gdb.BP_NONE
+gdb.Breakpoint.stop
+gdb.BreakpointEvent
+gdb.ClearObjFilesEvent
+gdb.Command.complete
+gdb.Command.invoke
+gdb.ConnectionEvent
+gdb.ContinueEvent
+gdb.DUMMY_FRAME
+gdb.Event
+gdb.EventRegistry
+gdb.ExitedEvent
+gdb.FRAME_UNWIND_FIRST_ERROR
+gdb.FinishBreakpoint.out_of_scope
+gdb.Function.invoke
+gdb.GdbExitingEvent
+gdb.GdbSetPythonDirectory
+gdb.HOST_CONFIG
+gdb.Inferior.connection
+gdb.Inferior.thread_from_thread_handle
+gdb.InferiorCallPostEvent
+gdb.InferiorCallPreEvent
+gdb.InferiorDeletedEvent
+gdb.InferiorThread.details
+gdb.Instruction
+gdb.LazyString
+gdb.LineTable.__next__
+gdb.LineTable.is_valid
+gdb.LineTable.source_lines
+gdb.LineTable.source_lnes
+gdb.LineTableIterator
+gdb.MICommand.invoke
+gdb.Membuf
+gdb.MemoryChangedEvent
+gdb.NewInferiorEvent
+gdb.NewObjFileEvent
+gdb.NewThreadEvent
+gdb.Objfile.frame_unwinders
+gdb.Objfile.lookup_static_method
+gdb.Objfile.lookup_static_symbol
+gdb.Objfile.xmethods
+gdb.Parameter.get_set_string
+gdb.Parameter.get_show_string
+gdb.Progspace.frame_unwinders
+gdb.Progspace.xmethods
+gdb.Record
+gdb.RecordFunctionSegment
+gdb.RecordGap
+gdb.RecordInstruction
+gdb.RegisterChangedEvent
+gdb.RegisterDescriptor
+gdb.RegisterDescriptorIterator
+gdb.RegisterGroup
+gdb.RegisterGroupsIterator
+gdb.RemoteTargetConnection
+gdb.SYMBOL_FUNCTIONS_DOMAIN
+gdb.SYMBOL_TYPES_DOMAIN
+gdb.SYMBOL_VARIABLES_DOMAIN
+gdb.SignalEvent
+gdb.StopEvent
+gdb.TARGET_CONFIG
+gdb.ThreadEvent
+gdb.TuiWindow
+gdb.Type.__contains__
+gdb.Type.get
+gdb.Type.has_key
+gdb.Type.is_scalar
+gdb.Type.is_signed
+gdb.Type.items
+gdb.Type.iteritems
+gdb.Type.iterkeys
+gdb.Type.itervalues
+gdb.Type.keys
+gdb.Type.values
+gdb.TypeIterator
+gdb.Unwinder
+gdb.Value.rvalue_reference_value
+gdb.frame_filters
+gdb.frame_unwinders
+gdb.packages
+gdb.prompt_hook
+gdb.type_printers
+gdb.xmethods
+gdb.events
+gdb.printing.RegexpCollectionPrettyPrinter.RegexpSubprinter
+gdb.printing.add_builtin_pretty_printer
+gdb.prompt.prompt_help
+gdb.prompt.prompt_substitutions
+gdb.types.TypePrinter.instantiate
+gdb.unwinder.Unwinder
+gdb.xmethod.SimpleXMethodMatcher
+gdb.xmethod.XMethodMatcher.match
+gdb.xmethod.XMethodWorker.__call__
+gdb.xmethod.XMethodWorker.get_arg_types
+gdb.xmethod.XMethodWorker.get_result_type
+gdb.FrameDecorator
+gdb.FrameIterator
+gdb.command
+gdb.command.explore
+gdb.command.frame_filters
+gdb.command.pretty_printers
+gdb.command.prompt
+gdb.command.type_printers
+gdb.command.unwinders
+gdb.command.xmethods
+gdb.frames
+gdb.function
+gdb.function.as_string
+gdb.function.caller_is
+gdb.function.strfns
+gdb.printer
+gdb.printer.bound_registers
+gdb.printing.basestring
+gdb.printing.long
+gdb.xmethod.basestring
+gdb.xmethod.long
+gdb.styling

stubs/gdb/METADATA.toml

@@ -11,6 +11,5 @@ extra_description = """\
 """
 
 [tool.stubtest]
-# Since the "gdb" Python package is available only inside GDB, it is not
-# possible to install it through pip, so stub tests cannot install it.
-skip = true
+platforms = ["linux"]
+apt_dependencies = ["gdb"]

tests/stubtest_third_party.py

@@ -73,6 +73,12 @@ def run_stubtest(
         # TODO: Maybe find a way to cache these in CI
         dists_to_install = [dist_req, get_mypy_req()]
         dists_to_install.extend(requirements.external_pkgs)  # Internal requirements are added to MYPYPATH
+
+        # Since the "gdb" Python package is available only inside GDB, it is not
+        # possible to install it through pip, so stub tests cannot install it.
+        if dist_name == "gdb":
+            dists_to_install[:] = dists_to_install[1:]
+
         pip_cmd = [pip_exe, "install", *dists_to_install]
         try:
             subprocess.run(pip_cmd, check=True, capture_output=True)
@@ -118,6 +124,10 @@ def run_stubtest(
             if not setup_uwsgi_stubtest_command(dist, venv_dir, stubtest_cmd):
                 return False
 
+        if dist_name == "gdb":
+            if not setup_gdb_stubtest_command(venv_dir, stubtest_cmd):
+                return False
+
         try:
             subprocess.run(stubtest_cmd, env=stubtest_env, check=True, capture_output=True)
         except subprocess.CalledProcessError as e:
@@ -153,6 +163,88 @@ def run_stubtest(
     return True
 
 
+def setup_gdb_stubtest_command(venv_dir: Path, stubtest_cmd: list[str]) -> bool:
+    """
+    Use wrapper scripts to run stubtest inside gdb.
+    The wrapper script is used to pass the arguments to the gdb script.
+    """
+    if sys.platform == "win32":
+        print_error("gdb is not supported on Windows")
+        return False
+
+    try:
+        gdb_version = subprocess.check_output(["gdb", "--version"], text=True, stderr=subprocess.STDOUT)
+    except FileNotFoundError:
+        print_error("gdb is not installed")
+        return False
+    if "Python scripting is not supported in this copy of GDB" in gdb_version:
+        print_error("Python scripting is not supported in this copy of GDB")
+        return False
+
+    gdb_script = venv_dir / "gdb_stubtest.py"
+    wrapper_script = venv_dir / "gdb_wrapper.py"
+    gdb_script_contents = dedent(
+        f"""
+        import json
+        import os
+        import site
+        import sys
+        import traceback
+
+        from glob import glob
+
+        # Add the venv site-packages to sys.path. gdb doesn't use the virtual environment.
+        # Taken from https://github.com/pwndbg/pwndbg/blob/83d8d95b576b749e888f533ce927ad5a77fb957b/gdbinit.py#L37
+        site_pkgs_path = glob(os.path.join({str(venv_dir)!r}, "lib/*/site-packages"))[0]
+        site.addsitedir(site_pkgs_path)
+
+        exit_code = 1
+        try:
+            # gdb wraps stdout and stderr without a .fileno
+            # colored output in mypy tries to access .fileno()
+            sys.stdout.fileno = sys.__stdout__.fileno
+            sys.stderr.fileno = sys.__stderr__.fileno
+
+            from mypy.stubtest import main
+
+            sys.argv = json.loads(os.environ.get("STUBTEST_ARGS"))
+            exit_code = main()
+        except Exception:
+            traceback.print_exc()
+        finally:
+            gdb.execute(f"quit {{exit_code}}")
+        """
+    )
+    gdb_script.write_text(gdb_script_contents)
+
+    wrapper_script_contents = dedent(
+        f"""
+        import json
+        import os
+        import subprocess
+        import sys
+
+        stubtest_env = os.environ | {{"STUBTEST_ARGS": json.dumps(sys.argv)}}
+        gdb_cmd = [
+            "gdb",
+            "--quiet",
+            "--nx",
+            "--batch",
+            "--command",
+            {str(gdb_script)!r},
+        ]
+        r = subprocess.run(gdb_cmd, env=stubtest_env)
+        sys.exit(r.returncode)
+        """
+    )
+    wrapper_script.write_text(wrapper_script_contents)
+
+    # replace "-m mypy.stubtest" in stubtest_cmd with the path to our wrapper script
+    assert stubtest_cmd[1:3] == ["-m", "mypy.stubtest"]
+    stubtest_cmd[1:3] = [str(wrapper_script)]
+    return True
+
+
 def setup_uwsgi_stubtest_command(dist: Path, venv_dir: Path, stubtest_cmd: list[str]) -> bool:
     """Perform some black magic in order to run stubtest inside uWSGI.