Test that header files include everything they need (#4496)

* Test that header files are standalone

* Working test

* Tests working

* Add doc string to header test file

* style

src/ngraph/op/fused/partial_slice.hpp

@@ -16,6 +16,7 @@
 
 #pragma once
 
+#include "ngraph/axis_vector.hpp"
 #include "ngraph/node.hpp"
 #include "ngraph/op/op.hpp"
 #include "ngraph/op/util/fused_op.hpp"

test/CMakeLists.txt

@@ -201,6 +201,33 @@ set(SRC
     zero_dim_tensor_elimination.cpp
 )
 
+# This code generates one source file per header file under ngraph/src where the source file
+# has just a single #include statement. This checks that each header in the source tree is
+# complete and self-contained so it can be included without requiring any other includes.
+set(DIRECTORIES_IGNORED runtime frontend)
+set(NGRAPH_MAIN_SRC_DIR "${CMAKE_SOURCE_DIR}/src/ngraph")
+file(GLOB_RECURSE LIST_RECURSE
+    "${NGRAPH_MAIN_SRC_DIR}/autodiff/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/builder/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/codegen/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/descriptor/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/distributed/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/op/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/pass/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/state*.hpp")
+file(GLOB LIST
+    "${NGRAPH_MAIN_SRC_DIR}/*.hpp"
+    "${NGRAPH_MAIN_SRC_DIR}/runtime/*.hpp")
+set(NGRAPH_HEADER_LIST ${LIST_RECURSE} ${LIST})
+list(APPEND NGRAPH_HEADER_LIST ${LIST})
+foreach(HEADER ${NGRAPH_HEADER_LIST})
+    file(RELATIVE_PATH OUT_PATH ${NGRAPH_MAIN_SRC_DIR} ${HEADER})
+    string(REGEX REPLACE "hpp$" "cpp" OUT_PATH ${OUT_PATH})
+    set(OUT_FILE "${CMAKE_CURRENT_BINARY_DIR}/include_test/${OUT_PATH}")
+    configure_file("header_standalone.in.cpp" ${OUT_FILE})
+    list(APPEND SRC ${OUT_FILE})
+endforeach()
+
 if(NGRAPH_JSON_ENABLE)
     list(APPEND SRC core.cpp serialize.cpp)
 endif()

test/header_standalone.in.cpp

+//*****************************************************************************
+// Copyright 2017-2020 Intel Corporation
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//*****************************************************************************
+
+/// \file This file is used to generate a series of .cpp files, one for each .hpp
+/// file in ngraph, so the line below `#include "${HEADER}"` is expanded out to something
+/// like `#include "/home/user/ngraph/src/ngraph/shape.hpp"`. The .cpp files are generated into
+/// build/test/include_test/<headers>
+/// The resulting .cpp file only includes this single file and then tries to compile it. If this
+/// header file (shape.hpp in this example) does not #include everything it needs then the compile
+/// will fail. You will need to add any missing #includes to make shape.hpp self-sufficient.
+#define NGRAPH_OP(...)
+#include "${HEADER}"
+#undef NGRAPH_OP