Add Unreal Engine 5 specific ignores, raises, docs and tests for C/C++ (#1564)

test/solidlsp/cpp/test_cpp_unreal_unit.py

@@ -0,0 +1,60 @@
+"""Unreal Engine handling in the clangd and ccls servers, without starting a process.
+
+No ``cpp`` marker: these build server shells with ``object.__new__`` and call the no-database
+and directory-ignore code paths directly, so they run in the default suite.
+"""
+
+import pytest
+
+from solidlsp.language_servers.ccls_language_server import CCLS
+from solidlsp.language_servers.clangd_language_server import ClangdLanguageServer
+from solidlsp.language_servers.common import UE_IGNORED_DIRNAMES, is_unreal_engine_project
+from solidlsp.ls_exceptions import SolidLSPException
+
+
+def _make_clangd(root) -> ClangdLanguageServer:
+    server = object.__new__(ClangdLanguageServer)
+    server.repository_root_path = str(root)
+    return server
+
+
+def _make_ccls(root) -> CCLS:
+    server = object.__new__(CCLS)
+    server.repository_root_path = str(root)
+    return server
+
+
+def test_is_unreal_engine_project_detection(tmp_path):
+    assert is_unreal_engine_project(str(tmp_path)) is False
+    (tmp_path / "MyGame.uproject").write_text("{}")
+    assert is_unreal_engine_project(str(tmp_path)) is True
+
+
+def test_missing_compile_commands_raises_for_unreal_project(tmp_path):
+    (tmp_path / "MyGame.uproject").write_text("{}")
+    server = _make_clangd(tmp_path)
+
+    with pytest.raises(SolidLSPException, match="Unreal Engine"):
+        server._prepare_compile_commands()
+
+
+def test_missing_compile_commands_returns_none_for_non_unreal_project(tmp_path):
+    server = _make_clangd(tmp_path)
+    assert server._prepare_compile_commands() is None
+
+
+@pytest.mark.parametrize("make_server", [_make_clangd, _make_ccls])
+def test_unreal_dirs_ignored_only_for_unreal_project(make_server, tmp_path):
+    non_ue = make_server(tmp_path)
+    for dirname in UE_IGNORED_DIRNAMES:
+        assert not non_ue.is_ignored_dirname(dirname), f"{dirname} should not be pruned without a .uproject"
+
+    ue_root = tmp_path / "ue"
+    ue_root.mkdir()
+    (ue_root / "MyGame.uproject").write_text("{}")
+    ue = make_server(ue_root)
+    for dirname in UE_IGNORED_DIRNAMES:
+        assert ue.is_ignored_dirname(dirname), f"{dirname} should be pruned for a UE project"
+
+    assert non_ue.is_ignored_dirname(".ccls-cache")
+    assert ue.is_ignored_dirname(".ccls-cache")