Cmake: Add backward compatibilty support for MBED_TEST_MODE

Fixes #14494

MBED_TEST_MODE is required for backward compatibilty with CLI1. This
adds a test to ensure that the macro is created when using CLI2 for
testing. This also adds a test in `.travis.yml` that checks whether
CMake defines the macro when BUILD_TESTING is on.

CLI1 Reference: https://os.mbed.com/docs/mbed-os/v6.9/debug-test/greentea-for-testing-applications.html

Also, explicitly create and set the macro BUILD_TESTING to allow for
MBED_TEST_MODE to be defined by CMake. MBED_TEST_MODE is required for
backward compatibilty with CLI1.  BUILD_TESTING is used to determine
whether to define MBED_TEST_MODE.  Normally, this would be automatically
done by CTest (which we intend to add for test automation) but this
hasn't yet been added to our Greentea tests.

Author: harrisonmutai-arm

.travis.yml

@@ -35,9 +35,14 @@ before_install:
 
 addons:
   apt:
+    sources:
+      - sourceline: 'deb https://apt.kitware.com/ubuntu/ xenial main'
+        key_url: 'https://apt.kitware.com/keys/kitware-archive-latest.asc'
     packages:
     - ninja-build
     - libncursesw5
+    - cmake
+    - ninja-build
 
 matrix:
   include:
@@ -279,3 +284,41 @@ matrix:
             | while read file; do python ./hal/tests/pinvalidate/pinvalidate.py -vfp "${file}"; done
         - git diff --exit-code --diff-filter=d --color
 
+    ### CMake Check ###
+    - &cmake-vm
+      stage: "CMake Check"
+      name: "Backward compatiblity check - MBED_TEST_MODE"
+      env: NAME=mbed-test-mode-check ROOT=tools/cmake/tests/mbed_test_mode/ TOOLCHAIN=GCC_ARM TARGET_NAME=K64F PROFILE=develop
+      language: python
+      python: 3.8
+      install:
+        # Hide Travis-preinstalled CMake
+        # The Travis-preinstalled CMake is unfortunately not installed via apt, so we
+        # can't replace it with an apt-supplied version very easily. Additionally, we
+        # can't permit the Travis-preinstalled copy to survive, as the Travis default
+        # path lists the Travis CMake install location ahead of any place where apt
+        # would install CMake to. Instead of apt removing or upgrading to a new CMake
+        # version, we must instead delete the Travis copy of CMake.
+        - sudo rm -rf /usr/local/cmake*
+        # Setup ccache
+        - ccache -o compiler_check=content
+        - ccache -M 1G
+        - pushd /usr/lib/ccache
+        - sudo ln -s ../../bin/ccache arm-none-eabi-gcc
+        - sudo ln -s ../../bin/ccache arm-none-eabi-g++
+        - export PATH="/usr/lib/ccache:$PATH"
+        - popd
+        # Install arm-none-eabi-gcc
+        - pushd /home/travis/build && mkdir arm-gcc && cd arm-gcc
+        - curl -L0 "https://developer.arm.com/-/media/Files/downloads/gnu-rm/9-2020q2/gcc-arm-none-eabi-9-2020-q2-update-x86_64-linux.tar.bz2?revision=05382cca-1721-44e1-ae19-1e7c3dc96118&la=en&hash=D7C9D18FCA2DD9F894FD9F3C3DC9228498FA281A" --output gcc-arm-none-eabi-9-2020-q2-update.tar.bz2
+        - tar xf gcc-arm-none-eabi-9-2020-q2-update.tar.bz2
+        - export PATH="$PATH:${PWD}/gcc-arm-none-eabi-9-2020-q2-update/bin"
+        - popd
+        - arm-none-eabi-gcc --version
+        # Install python modules
+        - pip install --upgrade mbed-tools
+        - pip install -r tools/cmake/requirements.txt
+      script:
+        - mbedtools configure -p ${ROOT} -t ${TOOLCHAIN} -m ${TARGET_NAME} --mbed-os-path .
+        - cmake -S ${ROOT} -B ${ROOT}/cmake_build/${TARGET_NAME}/${PROFILE}/${TOOLCHAIN}/ -GNinja -DCMAKE_BUILD_TYPE=${PROFILE}
+        - cmake --build ${ROOT}/cmake_build/${TARGET_NAME}/${PROFILE}/${TOOLCHAIN}/

CMakeLists.txt

@@ -79,6 +79,14 @@ target_compile_definitions(mbed-core
         ${MBED_CONFIG_DEFINITIONS}
 )
 
+# Add MBED_TEST_MODE for backward compatibility with Greentea tests written for use with Mbed CLI 1
+if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME AND BUILD_TESTING)
+    target_compile_definitions(${PROJECT_NAME}
+        PUBLIC
+            MBED_TEST_MODE
+    )
+endif()
+
 # We need to generate a "response file" to pass to the C preprocessor when we preprocess the linker
 # script, because of path length limitations on Windows. We set the response file and bind the path
 # to a global property here. The MBED_TARGET being built queries this global property when it sets

tools/cmake/mbed_greentea.cmake

@@ -41,6 +41,9 @@ macro(mbed_greentea_add_test)
 
     add_executable(${TEST_NAME})
 
+    # Explicitly enable BUILD_TESTING until CTest is added to the Greentea client
+    set(BUILD_TESTING ON)
+
     mbed_configure_app_target(${TEST_NAME})
 
     target_include_directories(${TEST_NAME}

tools/cmake/tests/mbed_test_mode/CMakeLists.txt

@@ -0,0 +1,20 @@
+# Copyright (c) 2020 ARM Limited. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+cmake_minimum_required(VERSION 3.19.0 FATAL_ERROR)
+
+set(MBED_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../../../.. CACHE INTERNAL "")
+set(MBED_CONFIG_PATH ${CMAKE_CURRENT_BINARY_DIR} CACHE STATIC "")
+
+include(${MBED_PATH}/tools/cmake/app.cmake)
+
+add_executable(mbed-test-mode-check)
+project(mbed-test-mode-check)
+
+set(PROJECT_NAME ${CMAKE_PROJECT_NAME} CACHE INTERNAL "")
+include(CTest)
+
+target_sources(mbed-test-mode-check
+    PRIVATE
+        main.cpp
+)

tools/cmake/tests/mbed_test_mode/main.cpp

@@ -0,0 +1,13 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2021 Arm Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#if BUILD_TESTING && !defined(MBED_TEST_MODE)
+#error "MBED_TEST_MODE not defined with BUILD_TESTING on"
+#else
+int main(){
+    return 1;
+}
+#endif