fix a few COTIRE_PREFIX_HEADER_INCLUDE_PRIORITY_PATH issues

CMake/cotire.cmake

@@ -1054,8 +1054,8 @@ endfunction()
 function (cotire_scan_includes _includesVar)
 	set(_options "")
 	set(_oneValueArgs COMPILER_ID COMPILER_EXECUTABLE COMPILER_VERSION INCLUDE_SYSTEM_FLAG LANGUAGE UNPARSED_LINES)
-	set(_multiValueArgs COMPILE_DEFINITIONS COMPILE_FLAGS INCLUDE_DIRECTORIES SYSTEM_INCLUDE_DIRECTORIES IGNORE_PATH INCLUDE_PATH IGNORE_EXTENSIONS,
-		INCLUDE_PRIORITY_PATH)
+	set(_multiValueArgs COMPILE_DEFINITIONS COMPILE_FLAGS INCLUDE_DIRECTORIES SYSTEM_INCLUDE_DIRECTORIES
+		IGNORE_PATH INCLUDE_PATH IGNORE_EXTENSIONS INCLUDE_PRIORITY_PATH)
 	cmake_parse_arguments(_option "${_options}" "${_oneValueArgs}" "${_multiValueArgs}" ${ARGN})
 	set (_sourceFiles ${_option_UNPARSED_ARGUMENTS})
 	if (NOT _option_LANGUAGE)
@@ -1105,7 +1105,6 @@ function (cotire_scan_includes _includesVar)
 		"${_option_IGNORE_EXTENSIONS}"
 		_includes _unparsedLines
 		${_sourceFiles})
-
 	if (_option_INCLUDE_PRIORITY_PATH)
 		set (_sortedIncludes "")
 		foreach (_priorityPath ${_option_INCLUDE_PRIORITY_PATH})
@@ -1116,10 +1115,11 @@ function (cotire_scan_includes _includesVar)
 				endif()
 			endforeach()
 		endforeach()
-		list (INSERT _includes 0 "${_sortedIncludes}")
-		list (REMOVE_DUPLICATES _includes)
+		if (_sortedIncludes)
+			list (INSERT _includes 0 ${_sortedIncludes})
+			list (REMOVE_DUPLICATES _includes)
+		endif()
 	endif()
-
 	set (${_includesVar} ${_includes} PARENT_SCOPE)
 	if (_option_UNPARSED_LINES)
 		set (${_option_UNPARSED_LINES} ${_unparsedLines} PARENT_SCOPE)
@@ -1271,8 +1271,8 @@ function (cotire_generate_prefix_header _prefixFile)
 	set(_options "")
 	set(_oneValueArgs LANGUAGE COMPILER_EXECUTABLE COMPILER_ID COMPILER_VERSION INCLUDE_SYSTEM_FLAG)
 	set(_multiValueArgs DEPENDS COMPILE_DEFINITIONS COMPILE_FLAGS
-		INCLUDE_DIRECTORIES SYSTEM_INCLUDE_DIRECTORIES IGNORE_PATH INCLUDE_PATH IGNORE_EXTENSIONS
-		INCLUDE_PRIORITY_PATH)
+		INCLUDE_DIRECTORIES SYSTEM_INCLUDE_DIRECTORIES IGNORE_PATH INCLUDE_PATH
+		IGNORE_EXTENSIONS INCLUDE_PRIORITY_PATH)
 	cmake_parse_arguments(_option "${_options}" "${_oneValueArgs}" "${_multiValueArgs}" ${ARGN})
 	if (_option_DEPENDS)
 		cotire_check_file_up_to_date(_prefixFileIsUpToDate "${_prefixFile}" ${_option_DEPENDS})
@@ -3169,7 +3169,7 @@ if (CMAKE_SCRIPT_MODE_FILE)
 			IGNORE_PATH "${COTIRE_TARGET_IGNORE_PATH};${COTIRE_ADDITIONAL_PREFIX_HEADER_IGNORE_PATH}"
 			INCLUDE_PATH ${COTIRE_TARGET_INCLUDE_PATH}
 			IGNORE_EXTENSIONS "${CMAKE_${COTIRE_TARGET_LANGUAGE}_SOURCE_FILE_EXTENSIONS};${COTIRE_ADDITIONAL_PREFIX_HEADER_IGNORE_EXTENSIONS}"
-			INCLUDE_PRIORITY_PATH "${COTIRE_TARGET_INCLUDE_PRIORITY_PATH}"
+			INCLUDE_PRIORITY_PATH ${COTIRE_TARGET_INCLUDE_PRIORITY_PATH}
 			INCLUDE_SYSTEM_FLAG "${COTIRE_INCLUDE_SYSTEM_FLAG}"
 			INCLUDE_DIRECTORIES ${_includeDirs}
 			SYSTEM_INCLUDE_DIRECTORIES ${_systemIncludeDirs}
@@ -3409,7 +3409,7 @@ else()
 
 	define_property(
 		DIRECTORY PROPERTY "COTIRE_PREFIX_HEADER_INCLUDE_PRIORITY_PATH"
-		BRIEF_DOCS "Header path matching one of these directories is put at the top of prefix header."
+		BRIEF_DOCS "Header paths matching one of these directories are put at the top of the prefix header."
 		FULL_DOCS
 			"See target property COTIRE_PREFIX_HEADER_INCLUDE_PRIORITY_PATH."
 	)
@@ -3501,17 +3501,15 @@ else()
 	)
 
 	define_property(
-		TARGET PROPERTY "COTIRE_PREFIX_HEADER_INCLUDE_PRIORITY_PATH"
-		BRIEF_DOCS "Header path matching one of these directories is put at the top of prefix header."
+		TARGET PROPERTY "COTIRE_PREFIX_HEADER_INCLUDE_PRIORITY_PATH" INHERITED
+		BRIEF_DOCS "Header paths matching one of these directories are put at the top of prefix header."
 		FULL_DOCS
 			"The property can be set to a list of directories."
-			"Headers files paths matching one of these directories will appear at the begin of generated prefix header."
-			"Order is kept from the property path order."
+			"Header file paths matching one of these directories will be inserted at the beginning of the generated prefix header."
+			"Header files are sorted according to the order of the directories in the property."
 			"If not set, this property is initialized to the empty list."
 	)
 
-
-
 	define_property(
 		TARGET PROPERTY "COTIRE_UNITY_SOURCE_PRE_UNDEFS" INHERITED
 		BRIEF_DOCS "Preprocessor undefs to place in the generated unity source file before the inclusion of each target source file."