add removed test cases

Also:
- Support cmake-format on Windows by using auto lione-ending

.cmake-format

@@ -1,6 +1,7 @@
 format:
   tab_size: 2
   line_width: 100
+  line_ending: auto
   dangle_parens: true
 
 parse:

cmake/CPM.cmake

@@ -505,6 +505,60 @@ function(cpm_override_fetchcontent contentName)
   set_property(GLOBAL PROPERTY ${propertyName} TRUE)
 endfunction()
 
+# replaces empty arguments with a placeholder to compensate CMake issues with handling empty
+# arguments
+function(cpm_encode_empty_arguments args outVar)
+  set(out "")
+  # note: we don't use string replacement for ';;' -> ';__CPM_EMPTY_ARG;' here, as it would
+  # interfere with nested arguments
+  foreach(ARG IN LISTS args)
+    if(NOT out STREQUAL "")
+      string(APPEND out ";")
+    endif()
+    if(ARG STREQUAL "")
+      string(APPEND out "__CPM_EMPTY_ARG")
+    else()
+      # prevent escaped characters from getting resolved early
+      string(REPLACE "\\" "\\\\\\" ARG "${ARG}")
+      string(APPEND out "${ARG}")
+    endif()
+  endforeach()
+  set("${outVar}"
+      "${out}"
+      PARENT_SCOPE
+  )
+endfunction()
+
+function(cpm_decode_empty_argument arg outVar)
+  if("${arg}" STREQUAL "__CPM_EMPTY_ARG")
+    set("${outVar}"
+        ""
+        PARENT_SCOPE
+    )
+  else()
+    set("${outVar}"
+        "${arg}"
+        PARENT_SCOPE
+    )
+  endif()
+endfunction()
+
+# replaces placeholder arguments from `cpm_encode_empty_arguments` with empty arguments
+function(cpm_decode_empty_arguments args outVar)
+  set(out "")
+  foreach(ARG IN LISTS args)
+    if(NOT out STREQUAL "")
+      string(APPEND out ";")
+    endif()
+    cpm_decode_empty_argument("${ARG}" ARG)
+    string(APPEND out "${ARG}")
+  endforeach()
+  set("${outVar}"
+      "${out}"
+      PARENT_SCOPE
+  )
+endfunction()
+
 # Download and add a package from source
 function(CPMAddPackage)
   cpm_set_policies()
@@ -512,7 +566,6 @@ function(CPMAddPackage)
   list(LENGTH ARGN argnLength)
   if(argnLength EQUAL 1)
     cpm_parse_add_package_single_arg("${ARGN}" ARGN)
-
     # The shorthand syntax implies EXCLUDE_FROM_ALL and SYSTEM
     set(ARGN "${ARGN};EXCLUDE_FROM_ALL;YES;SYSTEM;YES;")
   endif()
@@ -539,10 +592,26 @@ function(CPMAddPackage)
 
   set(multiValueArgs URL OPTIONS)
 
-  cmake_parse_arguments(CPM_ARGS "" "${oneValueArgs}" "${multiValueArgs}" "${ARGN}")
+  # Encode arguments for `cmake_parse_arguments`
+  cpm_encode_empty_arguments("${ARGN}" "PARSE_ARGS")
+
+  # Parse arguments
+  cmake_parse_arguments(CPM_ARGS "" "${oneValueArgs}" "${multiValueArgs}" "${PARSE_ARGS}")
+
+  # Decode arguments
+  foreach(ARG IN LISTS oneValueArgs)
+    if(DEFINED CPM_ARGS_${ARG})
+      cpm_decode_empty_argument("${CPM_ARGS_${ARG}}" CPM_ARGS_${ARG})
+    endif()
+  endforeach()
+  foreach(ARG IN LISTS multiValueArgs)
+    if(DEFINED CPM_ARGS_${ARG})
+      cpm_decode_empty_arguments("${CPM_ARGS_${ARG}}" CPM_ARGS_${ARG})
+    endif()
+  endforeach()
+  cpm_decode_empty_arguments("${CPM_ARGS_UNPARSED_ARGUMENTS}" CPM_ARGS_UNPARSED_ARGUMENTS)
 
   # Set default values for arguments
-
   if(NOT DEFINED CPM_ARGS_VERSION)
     if(DEFINED CPM_ARGS_GIT_TAG)
       cpm_get_version_from_git_tag("${CPM_ARGS_GIT_TAG}" CPM_ARGS_VERSION)
@@ -916,8 +985,7 @@ function(cpm_declare_fetch PACKAGE VERSION INFO)
     cpm_message(STATUS "${CPM_INDENT} Package not declared (dry run)")
     return()
   endif()
-
-  FetchContent_Declare(${PACKAGE} ${ARGN})
+  FetchContent_Declare(${PACKAGE} "${ARGN}")
 endfunction()
 
 # returns properties for a package previously defined by cpm_declare_fetch
@@ -1105,7 +1173,7 @@ function(cpm_prettify_package_arguments OUT_VAR IS_IN_COMMENT)
       GIT_SHALLOW
   )
   set(multiValueArgs OPTIONS)
-  cmake_parse_arguments(CPM_ARGS "" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
+  cmake_parse_arguments(PARSE_ARGV 2 CPM_ARGS "" "${oneValueArgs}" "${multiValueArgs}")
 
   foreach(oneArgName ${oneValueArgs})
     if(DEFINED CPM_ARGS_${oneArgName})

test/integration/README.md

@@ -12,7 +12,7 @@ To run all tests from the repo root execute:
 $ ruby test/integration/runner.rb
 ```
 
-The runner will run all tests and generate a report of the exeuction.
+The runner will run all tests and generate a report of the execution.
 
 The current working directory doesn't matter. If you are in `<repo-root>/test/integration`, you can run simply `$ ruby runner.rb`.
 

test/unit/forward_arguments.cmake

@@ -0,0 +1,69 @@
+cmake_minimum_required(VERSION 3.14 FATAL_ERROR)
+
+include(${CPM_PATH}/CPM.cmake)
+include(${CPM_PATH}/testing.cmake)
+
+set(input "a;;b;c;;;;def;g;;")
+cpm_encode_empty_arguments("${input}" encoded)
+foreach(arg IN LISTS encoded)
+  assert_not_equal("${arg}" "")
+endforeach()
+assert_equal("${contains_empty_arg}" "")
+cpm_decode_empty_arguments("${encoded}" decoded)
+assert_equal("${decoded}" "${input}")
+
+# ignore source cache if set
+set(CPM_SOURCE_CACHE "")
+
+# Intercept underlying `FetchContent_Declare`
+function(FetchContent_Declare)
+  set_property(GLOBAL PROPERTY last_FetchContent_Declare_ARGN "${ARGN}")
+endfunction()
+cpm_declare_fetch(PACKAGE VERSION INFO EMPTY "" ANOTHER)
+
+# TEST:`cpm_declare_fetch` shall forward empty arguments
+get_property(last_FetchContent_Declare_ARGN GLOBAL PROPERTY last_FetchContent_Declare_ARGN)
+assert_equal("${last_FetchContent_Declare_ARGN}" "PACKAGE;EMPTY;;ANOTHER")
+
+# TEST:`CPMDeclarePackage` shall store all including empty
+CPMDeclarePackage(FOO EMPTY "" ANOTHER)
+assert_equal("${CPM_DECLARATION_FOO}" "EMPTY;;ANOTHER")
+
+# Stub the actual fetch
+set(fibonacci_POPULATED YES)
+set(fibonacci_SOURCE_DIR ".")
+set(fibonacci_BINARY_DIR ".")
+macro(FetchContent_GetProperties)
+
+endmacro()
+
+# TEST:`CPMAddPackage` shall call `FetchContent_declare` with unmodified arguments including any
+# Empty-string arguments
+CPMAddPackage(
+  NAME fibonacci
+  GIT_REPOSITORY https://github.com/cpm-cmake/testpack-fibonacci.git
+  VERSION 1.2.3 EMPTY_OPTION "" COMMAND_WITH_EMPTY_ARG foo "" bar
+)
+get_property(last_FetchContent_Declare_ARGN GLOBAL PROPERTY last_FetchContent_Declare_ARGN)
+assert_equal(
+  "${last_FetchContent_Declare_ARGN}"
+  "fibonacci;EMPTY_OPTION;;COMMAND_WITH_EMPTY_ARG;foo;;bar;GIT_REPOSITORY;https://github.com/cpm-cmake/testpack-fibonacci.git;GIT_TAG;v1.2.3"
+)
+
+# Intercept underlying `cpm_add_package_multi_arg`
+function(CPMAddPackage)
+  set_property(GLOBAL PROPERTY last_cpmaddpackage_argn "${ARGN}")
+endfunction()
+
+# TEST: CPM Module file shall store all arguments including empty strings
+include(${CPM_MODULE_PATH}/Findfibonacci.cmake)
+
+get_property(last_cpmaddpackage_argn GLOBAL PROPERTY last_cpmaddpackage_argn)
+assert_equal(
+  "${last_cpmaddpackage_argn}"
+  "NAME;fibonacci;GIT_REPOSITORY;https://github.com/cpm-cmake/testpack-fibonacci.git;VERSION;1.2.3;EMPTY_OPTION;;COMMAND_WITH_EMPTY_ARG;foo;;bar"
+)
+
+# remove generated files
+file(REMOVE_RECURSE ${CPM_MODULE_PATH})
+file(REMOVE ${CPM_PACKAGE_LOCK_FILE})

test/unit/options.cmake

@@ -2,6 +2,8 @@ include(CMakePackageConfigHelpers)
 include(${CPM_PATH}/testing.cmake)
 
 set(TEST_BUILD_DIR ${CMAKE_CURRENT_BINARY_DIR}/source_dir)
+# clean existing build if it exists
+file(REMOVE_RECURSE "${TEST_BUILD_DIR}")
 
 set(TEST_DEPENDENCY_NAME Dependency)