CMake: Remove duplicate find_package

Packages of third-party dependencies were searched twice. Once when adding them via wx_add_thirdparty_library to determine if they are available or of the built-in library should be used. And then again when including the third-party cmake file. Move all the logic into the third-party library cmake file.

This also removes the need to move the WebP variables into the parent scope.

build/cmake/functions.cmake

@@ -718,14 +718,6 @@ function(wx_add_thirdparty_library var_name lib_name help_str)
     wx_option(${var_name} ${help_str} ${thirdparty_lib_default}
         STRINGS builtin sys OFF)
 
-    if(${var_name} STREQUAL "sys")
-        # If the sys library can not be found use builtin
-        find_package(${lib_name})
-        if(NOT ${lib_name}_FOUND)
-            wx_option_force_value(${var_name} builtin)
-        endif()
-    endif()
-
     set(wxTHIRD_PARTY_LIBRARIES ${wxTHIRD_PARTY_LIBRARIES} ${var_name} "${help_str}" PARENT_SCOPE)
 endfunction()
 

build/cmake/lib/expat.cmake

@@ -7,6 +7,14 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_EXPAT STREQUAL "sys")
+    find_package(EXPAT)
+    if(NOT EXPAT_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_EXPAT builtin)
+    endif()
+endif()
+
 if(wxUSE_EXPAT STREQUAL "builtin")
     # TODO: implement building expat via its CMake file, using
     # add_subdirectory or ExternalProject_Add
@@ -17,6 +25,4 @@ if(wxUSE_EXPAT STREQUAL "builtin")
     )
     set(EXPAT_LIBRARIES wxexpat)
     set(EXPAT_INCLUDE_DIRS ${wxSOURCE_DIR}/src/expat/expat/lib)
-elseif(wxUSE_EXPAT)
-    find_package(EXPAT REQUIRED)
 endif()

build/cmake/lib/jpeg.cmake

@@ -7,6 +7,14 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_LIBJPEG STREQUAL "sys")
+    find_package(JPEG)
+    if(NOT JPEG_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_LIBJPEG builtin)
+    endif()
+endif()
+
 if(wxUSE_LIBJPEG STREQUAL "builtin")
     wx_add_builtin_library(wxjpeg
         src/jpeg/jaricom.c
@@ -62,6 +70,4 @@ if(wxUSE_LIBJPEG STREQUAL "builtin")
         )
     set(JPEG_LIBRARIES wxjpeg)
     set(JPEG_INCLUDE_DIR ${wxSOURCE_DIR}/src/jpeg)
-elseif(wxUSE_LIBJPEG)
-    find_package(JPEG REQUIRED)
 endif()

build/cmake/lib/nanosvg.cmake

@@ -7,6 +7,14 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_NANOSVG STREQUAL "sys")
+    find_package(NanoSVG)
+    if(NOT NanoSVG_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_NANOSVG builtin)
+    endif()
+endif()
+
 if(wxUSE_NANOSVG STREQUAL "builtin")
     set(wxUSE_NANOSVG_EXTERNAL 0 PARENT_SCOPE)
 elseif(wxUSE_NANOSVG)
@@ -16,8 +24,6 @@ elseif(wxUSE_NANOSVG)
     set(NANOSVG_INCLUDE_DIRS )
     set(wxUSE_NANOSVG_EXTERNAL_ENABLE_IMPL TRUE)
 
-    find_package(NanoSVG REQUIRED)
-
     foreach(TARGETNAME NanoSVG::nanosvg NanoSVG::nanosvgrast unofficial::nanosvg)
         if(NOT TARGET ${TARGETNAME})
             continue()

build/cmake/lib/png.cmake

@@ -7,6 +7,14 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_LIBPNG STREQUAL "sys")
+    find_package(PNG)
+    if(NOT PNG_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_LIBPNG builtin)
+    endif()
+endif()
+
 if(wxUSE_LIBPNG STREQUAL "builtin")
     # TODO: implement building libpng via its CMake file, using
     # add_subdirectory or ExternalProject_Add
@@ -53,6 +61,4 @@ if(wxUSE_LIBPNG STREQUAL "builtin")
     target_link_libraries(wxpng PRIVATE ${ZLIB_LIBRARIES})
     set(PNG_LIBRARIES wxpng)
     set(PNG_INCLUDE_DIRS ${wxSOURCE_DIR}/src/png)
-elseif(wxUSE_LIBPNG)
-    find_package(PNG REQUIRED)
 endif()

build/cmake/lib/regex.cmake

@@ -7,6 +7,17 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_REGEX STREQUAL "sys")
+    find_package(PCRE2)
+    if(NOT PCRE2_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_REGEX builtin)
+    else()
+        set(REGEX_LIBRARIES ${PCRE2_LIBRARIES})
+        set(REGEX_INCLUDE_DIRS ${PCRE2_INCLUDE_DIRS})
+    endif()
+endif()
+
 if(wxUSE_REGEX STREQUAL "builtin")
     # TODO: implement building PCRE2 via its CMake file, using
     # add_subdirectory or ExternalProject_Add
@@ -45,8 +56,4 @@ if(wxUSE_REGEX STREQUAL "builtin")
     set(REGEX_INCLUDE_DIRS ${wxSOURCE_DIR}/3rdparty/pcre/src/wx)
     target_compile_definitions(wxregex PRIVATE __WX__ HAVE_CONFIG_H)
     target_include_directories(wxregex PRIVATE ${wxSETUP_HEADER_PATH} ${wxSOURCE_DIR}/include ${REGEX_INCLUDE_DIRS})
-elseif(wxUSE_REGEX)
-    find_package(PCRE2 REQUIRED)
-    set(REGEX_LIBRARIES ${PCRE2_LIBRARIES})
-    set(REGEX_INCLUDE_DIRS ${PCRE2_INCLUDE_DIRS})
 endif()

build/cmake/lib/tiff.cmake

@@ -7,6 +7,14 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_LIBTIFF STREQUAL "sys")
+    find_package(TIFF)
+    if(NOT TIFF_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_LIBTIFF builtin)
+    endif()
+endif()
+
 if(wxUSE_LIBTIFF STREQUAL "builtin")
     # TODO: implement building libtiff via its CMake file, using
     # add_subdirectory or ExternalProject_Add
@@ -76,6 +84,4 @@ if(wxUSE_LIBTIFF STREQUAL "builtin")
     target_link_libraries(wxtiff PRIVATE ${ZLIB_LIBRARIES} ${JPEG_LIBRARIES})
     set(TIFF_LIBRARIES wxtiff)
     set(TIFF_INCLUDE_DIRS ${wxSOURCE_DIR}/src/tiff/libtiff)
-elseif(wxUSE_LIBTIFF)
-    find_package(TIFF REQUIRED)
 endif()

build/cmake/lib/webp.cmake

@@ -7,6 +7,14 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_LIBWEBP STREQUAL "sys")
+    find_package(WebP)
+    if(NOT WebP_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_LIBWEBP builtin)
+    endif()
+endif()
+
 if(wxUSE_LIBWEBP STREQUAL "builtin")
     set(WEBP_ROOT "${wxSOURCE_DIR}/3rdparty/libwebp")
     set(WEBP_BUILD_ROOT "${CMAKE_CURRENT_BINARY_DIR}/webp-build")

build/cmake/lib/zlib.cmake

@@ -7,6 +7,14 @@
 # Licence:     wxWindows licence
 #############################################################################
 
+if(wxUSE_ZLIB STREQUAL "sys")
+    find_package(ZLIB)
+    if(NOT ZLIB_FOUND)
+        # If the sys library can not be found use builtin
+        wx_option_force_value(wxUSE_ZLIB builtin)
+    endif()
+endif()
+
 if(wxUSE_ZLIB STREQUAL "builtin")
     # TODO: implement building zlib via its CMake file, using
     # add_subdirectory or ExternalProject_Add
@@ -40,6 +48,4 @@ if(wxUSE_ZLIB STREQUAL "builtin")
     endif()
     set(ZLIB_LIBRARIES wxzlib)
     set(ZLIB_INCLUDE_DIRS ${wxSOURCE_DIR}/src/zlib)
-elseif(wxUSE_ZLIB)
-    find_package(ZLIB REQUIRED)
 endif()

build/cmake/modules/FindWebP.cmake

@@ -6,6 +6,3 @@ if(NOT WebP_FOUND)
         pkg_check_modules(WebP libwebp)
     endif()
 endif()
-
-set(WebP_LIBRARIES ${WebP_LIBRARIES} PARENT_SCOPE)
-set(WebP_INCLUDE_DIRS ${WebP_INCLUDE_DIRS} PARENT_SCOPE)