CatchAddTests.cmake: Refactor into callable method

Move test discovery logic into new catch_discover_tests_impl method
and make CatchAddTests aware of whether it is being launched in
CMake's script mode.

When launched in script mode, catch_discover_tests_impl is called
passing arguments obtained from the definitions passed into the call
to cmake. This preserves the existing behavior assumed by Catch.cmake.

Looking ahead, it also allows CatchAddTests to be included in
generated files and call catch_discover_tests_impl to perform test
discovery at test runtime with the new PRE_TEST discovery mode
introduced later.

1 files changed, 150 insertions, 119 deletions

diff --git a/extras/CatchAddTests.cmake b/extras/CatchAddTests.cmake
index 2df663dc..91f79f3c 100644
--- a/extras/CatchAddTests.cmake
+++ b/extras/CatchAddTests.cmake
@@ -1,28 +1,6 @@
 # Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
 # file Copyright.txt or https://cmake.org/licensing for details.
 
-set(prefix "${TEST_PREFIX}")
-set(suffix "${TEST_SUFFIX}")
-set(spec ${TEST_SPEC})
-set(extra_args ${TEST_EXTRA_ARGS})
-set(properties ${TEST_PROPERTIES})
-set(reporter ${TEST_REPORTER})
-set(output_dir ${TEST_OUTPUT_DIR})
-set(output_prefix ${TEST_OUTPUT_PREFIX})
-set(output_suffix ${TEST_OUTPUT_SUFFIX})
-set(dl_paths ${TEST_DL_PATHS})
-set(script)
-set(suite)
-set(tests)
-
-if(WIN32)
-  set(dl_paths_variable_name PATH)
-elseif(APPLE)
-  set(dl_paths_variable_name DYLD_LIBRARY_PATH)
-else()
-  set(dl_paths_variable_name LD_LIBRARY_PATH)
-endif()
-
 function(add_command NAME)
   set(_args "")
   # use ARGV* instead of ARGN, because ARGN splits arrays into multiple arguments
@@ -38,119 +16,172 @@ function(add_command NAME)
   set(script "${script}${NAME}(${_args})\n" PARENT_SCOPE)
 endfunction()
 
-# Run test executable to get list of available tests
-if(NOT EXISTS "${TEST_EXECUTABLE}")
-  message(FATAL_ERROR
-    "Specified test executable '${TEST_EXECUTABLE}' does not exist"
-  )
-endif()
-
-if(dl_paths)
-  cmake_path(CONVERT "${dl_paths}" TO_NATIVE_PATH_LIST paths)
-  set(ENV{${dl_paths_variable_name}} "${paths}")
-endif()
+function(catch_discover_tests_impl)
 
-execute_process(
-  COMMAND ${TEST_EXECUTOR} "${TEST_EXECUTABLE}" ${spec} --list-tests --verbosity quiet
-  OUTPUT_VARIABLE output
-  RESULT_VARIABLE result
-  WORKING_DIRECTORY "${TEST_WORKING_DIR}"
-)
-if(NOT ${result} EQUAL 0)
-  message(FATAL_ERROR
-    "Error running test executable '${TEST_EXECUTABLE}':\n"
-    "  Result: ${result}\n"
-    "  Output: ${output}\n"
+  cmake_parse_arguments(
+    ""
+    ""
+    "TEST_EXECUTABLE;TEST_WORKING_DIR;TEST_DL_PATHS;TEST_OUTPUT_DIR;TEST_OUTPUT_PREFIX;TEST_OUTPUT_SUFFIX;TEST_PREFIX;TEST_REPORTER;TEST_SPEC;TEST_SUFFIX;TEST_LIST;CTEST_FILE"
+    "TEST_EXTRA_ARGS;TEST_PROPERTIES;TEST_EXECUTOR"
+    ${ARGN}
   )
-endif()
 
-string(REPLACE "\n" ";" output "${output}")
+  set(prefix "${_TEST_PREFIX}")
+  set(suffix "${_TEST_SUFFIX}")
+  set(spec ${_TEST_SPEC})
+  set(extra_args ${_TEST_EXTRA_ARGS})
+  set(properties ${_TEST_PROPERTIES})
+  set(reporter ${_TEST_REPORTER})
+  set(output_dir ${_TEST_OUTPUT_DIR})
+  set(output_prefix ${_TEST_OUTPUT_PREFIX})
+  set(output_suffix ${_TEST_OUTPUT_SUFFIX})
+  set(dl_paths ${_TEST_DL_PATHS})
+  set(script)
+  set(suite)
+  set(tests)
+
+  if(WIN32)
+    set(dl_paths_variable_name PATH)
+  elseif(APPLE)
+    set(dl_paths_variable_name DYLD_LIBRARY_PATH)
+  else()
+    set(dl_paths_variable_name LD_LIBRARY_PATH)
+  endif()
 
-# Prepare reporter
-if(reporter)
-  set(reporter_arg "--reporter ${reporter}")
+  # Run test executable to get list of available tests
+  if(NOT EXISTS "${_TEST_EXECUTABLE}")
+    message(FATAL_ERROR
+      "Specified test executable '${_TEST_EXECUTABLE}' does not exist"
+    )
+  endif()
+
+  if(dl_paths)
+    cmake_path(CONVERT "${dl_paths}" TO_NATIVE_PATH_LIST paths)
+    set(ENV{${dl_paths_variable_name}} "${paths}")
+  endif()
 
-  # Run test executable to check whether reporter is available
-  # note that the use of --list-reporters is not the important part,
-  # we only want to check whether the execution succeeds with ${reporter_arg}
   execute_process(
-    COMMAND ${TEST_EXECUTOR} "${TEST_EXECUTABLE}" ${spec} ${reporter_arg} --list-reporters
-    OUTPUT_VARIABLE reporter_check_output
-    RESULT_VARIABLE reporter_check_result
-    WORKING_DIRECTORY "${TEST_WORKING_DIR}"
+    COMMAND ${_TEST_EXECUTOR} "${_TEST_EXECUTABLE}" ${spec} --list-tests --verbosity quiet
+    OUTPUT_VARIABLE output
+    RESULT_VARIABLE result
+    WORKING_DIRECTORY "${_TEST_WORKING_DIR}"
   )
-  if(${reporter_check_result} EQUAL 255)
-    message(FATAL_ERROR
-      "\"${reporter}\" is not a valid reporter!\n"
-    )
-  elseif(NOT ${reporter_check_result} EQUAL 0)
+  if(NOT ${result} EQUAL 0)
     message(FATAL_ERROR
-      "Error running test executable '${TEST_EXECUTABLE}':\n"
-      "  Result: ${reporter_check_result}\n"
-      "  Output: ${reporter_check_output}\n"
+      "Error running test executable '${_TEST_EXECUTABLE}':\n"
+      "  Result: ${result}\n"
+      "  Output: ${output}\n"
     )
   endif()
-endif()
 
-# Prepare output dir
-if(output_dir AND NOT IS_ABSOLUTE ${output_dir})
-  set(output_dir "${TEST_WORKING_DIR}/${output_dir}")
-  if(NOT EXISTS ${output_dir})
-    file(MAKE_DIRECTORY ${output_dir})
+  string(REPLACE "\n" ";" output "${output}")
+
+  # Prepare reporter
+  if(reporter)
+    set(reporter_arg "--reporter ${reporter}")
+
+    # Run test executable to check whether reporter is available
+    # note that the use of --list-reporters is not the important part,
+    # we only want to check whether the execution succeeds with ${reporter_arg}
+    execute_process(
+      COMMAND ${TEST_EXECUTOR} "${TEST_EXECUTABLE}" ${spec} ${reporter_arg} --list-reporters
+      OUTPUT_VARIABLE reporter_check_output
+      RESULT_VARIABLE reporter_check_result
+      WORKING_DIRECTORY "${TEST_WORKING_DIR}"
+    )
+    if(${reporter_check_result} EQUAL 255)
+      message(FATAL_ERROR
+        "\"${reporter}\" is not a valid reporter!\n"
+      )
+    elseif(NOT ${reporter_check_result} EQUAL 0)
+      message(FATAL_ERROR
+        "Error running test executable '${TEST_EXECUTABLE}':\n"
+        "  Result: ${reporter_check_result}\n"
+        "  Output: ${reporter_check_output}\n"
+      )
+    endif()
   endif()
-endif()
 
-if(dl_paths)
-  foreach(path ${dl_paths})
-    cmake_path(NATIVE_PATH path native_path)
-    list(APPEND environment_modifications "${dl_paths_variable_name}=path_list_prepend:${native_path}")
-  endforeach()
-endif()
+  # Prepare output dir
+  if(output_dir AND NOT IS_ABSOLUTE ${output_dir})
+    set(output_dir "${_TEST_WORKING_DIR}/${output_dir}")
+    if(NOT EXISTS ${output_dir})
+      file(MAKE_DIRECTORY ${output_dir})
+    endif()
+  endif()
 
-# Parse output
-foreach(line ${output})
-  set(test ${line})
-  # Escape characters in test case names that would be parsed by Catch2
-  set(test_name ${test})
-  foreach(char , [ ])
-    string(REPLACE ${char} "\\${char}" test_name ${test_name})
-  endforeach(char)
-  # ...add output dir
-  if(output_dir)
-    string(REGEX REPLACE "[^A-Za-z0-9_]" "_" test_name_clean ${test_name})
-    set(output_dir_arg "--out ${output_dir}/${output_prefix}${test_name_clean}${output_suffix}")
+  if(dl_paths)
+    foreach(path ${dl_paths})
+      cmake_path(NATIVE_PATH path native_path)
+      list(APPEND environment_modifications "${dl_paths_variable_name}=path_list_prepend:${native_path}")
+    endforeach()
   endif()
-  
-  # ...and add to script
-  add_command(add_test
-    "${prefix}${test}${suffix}"
-    ${TEST_EXECUTOR}
-    "${TEST_EXECUTABLE}"
-    "${test_name}"
-    ${extra_args}
-    "${reporter_arg}"
-    "${output_dir_arg}"
-  )
-  add_command(set_tests_properties
-    "${prefix}${test}${suffix}"
-    PROPERTIES
-    WORKING_DIRECTORY "${TEST_WORKING_DIR}"
-    ${properties}
-  )
 
-   if(environment_modifications)
-     add_command(set_tests_properties
-       "${prefix}${test}${suffix}"
-       PROPERTIES
-       ENVIRONMENT_MODIFICATION "${environment_modifications}")
-   endif()
+  # Parse output
+  foreach(line ${output})
+    set(test ${line})
+    # Escape characters in test case names that would be parsed by Catch2
+    set(test_name ${test})
+    foreach(char , [ ])
+      string(REPLACE ${char} "\\${char}" test_name ${test_name})
+    endforeach(char)
+    # ...add output dir
+    if(output_dir)
+      string(REGEX REPLACE "[^A-Za-z0-9_]" "_" test_name_clean ${test_name})
+      set(output_dir_arg "--out ${output_dir}/${output_prefix}${test_name_clean}${output_suffix}")
+    endif()
 
-  list(APPEND tests "${prefix}${test}${suffix}")
-endforeach()
+    # ...and add to script
+    add_command(add_test
+      "${prefix}${test}${suffix}"
+      ${_TEST_EXECUTOR}
+      "${_TEST_EXECUTABLE}"
+      "${test_name}"
+      ${extra_args}
+      "${reporter_arg}"
+      "${output_dir_arg}"
+    )
+    add_command(set_tests_properties
+      "${prefix}${test}${suffix}"
+      PROPERTIES
+      WORKING_DIRECTORY "${_TEST_WORKING_DIR}"
+      ${properties}
+    )
+
+    if(environment_modifications)
+      add_command(set_tests_properties
+        "${prefix}${test}${suffix}"
+        PROPERTIES
+        ENVIRONMENT_MODIFICATION "${environment_modifications}")
+    endif()
+
+    list(APPEND tests "${prefix}${test}${suffix}")
+  endforeach()
 
-# Create a list of all discovered tests, which users may use to e.g. set
-# properties on the tests
-add_command(set ${TEST_LIST} ${tests})
+  # Create a list of all discovered tests, which users may use to e.g. set
+  # properties on the tests
+  add_command(set ${_TEST_LIST} ${tests})
 
-# Write CTest script
-file(WRITE "${CTEST_FILE}" "${script}")
+  # Write CTest script
+  file(WRITE "${_CTEST_FILE}" "${script}")
+endfunction()
+
+if(CMAKE_SCRIPT_MODE_FILE)
+  catch_discover_tests_impl(
+    TEST_EXECUTABLE ${TEST_EXECUTABLE}
+    TEST_EXECUTOR ${TEST_EXECUTOR}
+    TEST_WORKING_DIR ${TEST_WORKING_DIR}
+    TEST_SPEC ${TEST_SPEC}
+    TEST_EXTRA_ARGS ${TEST_EXTRA_ARGS}
+    TEST_PROPERTIES ${TEST_PROPERTIES}
+    TEST_PREFIX ${TEST_PREFIX}
+    TEST_SUFFIX ${TEST_SUFFIX}
+    TEST_LIST ${TEST_LIST}
+    TEST_REPORTER ${TEST_REPORTER}
+    TEST_OUTPUT_DIR ${TEST_OUTPUT_DIR}
+    TEST_OUTPUT_PREFIX ${TEST_OUTPUT_PREFIX}
+    TEST_OUTPUT_SUFFIX ${TEST_OUTPUT_SUFFIX}
+    TEST_DL_PATHS ${TEST_DL_PATHS}
+    CTEST_FILE ${CTEST_FILE}
+  )
+endif()