fix(tests): use correct include path for unittest

Copy whatever was made to work for generated headers:

(1) we need to consider all cmake targets not just main_lib
(2) we need to add the sysroot for macOS

build.zig

@@ -408,6 +408,7 @@ pub fn test_config(b: *std.Build, gen_dir: LazyPath) ![]u8 {
         \\local M = {{}}
         \\
         \\M.include_paths = {{}}
+        \\M.apple_sysroot = ""
         \\M.translations_enabled = "$ENABLE_TRANSLATIONS" == "ON"
         \\M.is_asan = "$ENABLE_ASAN_UBSAN" == "ON"
         \\M.is_zig_build = true

src/nvim/CMakeLists.txt

@@ -481,11 +481,13 @@ foreach(target ${targets})
     message(STATUS "${target} props '${prop}'")
     foreach(gen_include ${prop})
       list(APPEND gen_cflags "-I${gen_include}")
+      list(APPEND TEST_INCLUDE_DIRS "${gen_include}")
     endforeach()
   endif()
 endforeach()
 
 list(REMOVE_DUPLICATES gen_cflags)
+list(REMOVE_DUPLICATES TEST_INCLUDE_DIRS)
 
 if(APPLE AND CMAKE_OSX_SYSROOT)
   list(APPEND gen_cflags "-isysroot" "${CMAKE_OSX_SYSROOT}")

test/CMakeLists.txt

@@ -1,6 +1,6 @@
 add_subdirectory(functional/fixtures)  # compile test programs
 
-get_target_property(TEST_INCLUDE_DIRS main_lib INTERFACE_INCLUDE_DIRECTORIES)
+get_directory_property(TEST_INCLUDE_DIRS DIRECTORY ${PROJECT_SOURCE_DIR}/src/nvim DEFINITION TEST_INCLUDE_DIRS)
 
 set(TEST_OPTIONS
       -D BUILD_DIR=${CMAKE_BINARY_DIR}

test/cmakeconfig/paths.lua.in

@@ -4,6 +4,7 @@ M.include_paths = {}
 for p in ("${TEST_INCLUDE_DIRS}" .. ";"):gmatch("[^;]+") do
   table.insert(M.include_paths, p)
 end
+M.apple_sysroot = "${CMAKE_OSX_SYSROOT}"
 
 M.translations_enabled = "${ENABLE_TRANSLATIONS}" == "ON"
 M.is_asan = "${ENABLE_ASAN_UBSAN}" == "ON"

test/unit/preprocess.lua

@@ -146,13 +146,20 @@ end
 
 --- @param ... string
 function Gcc:add_to_include_path(...)
+  local ef = self.preprocessor_extra_flags
   for i = 1, select('#', ...) do
     local path = select(i, ...)
-    local ef = self.preprocessor_extra_flags
     ef[#ef + 1] = '-I' .. path
   end
 end
 
+function Gcc:add_apple_sysroot(sysroot)
+  local ef = self.preprocessor_extra_flags
+
+  table.insert(ef, '-isysroot')
+  table.insert(ef, sysroot)
+end
+
 -- returns a list of the headers files upon which this file relies
 --- @param hdr string
 --- @return string[]?
@@ -278,4 +285,9 @@ function M.add_to_include_path(...)
   return cc:add_to_include_path(...)
 end
 
+--- @param ... string
+function M.add_apple_sysroot(...)
+  return cc:add_apple_sysroot(...)
+end
+
 return M

test/unit/testutil.lua

@@ -19,6 +19,11 @@ for _, p in ipairs(paths.include_paths) do
   Preprocess.add_to_include_path(p)
 end
 
+-- add some nonstandard header locations
+if paths.apple_sysroot ~= '' then
+  Preprocess.add_apple_sysroot(paths.apple_sysroot)
+end
+
 local child_pid = nil --- @type integer?
 --- @generic F: function
 --- @param func F