meson: Simplify some bits by using newer syntax

src/api/meson.build

@@ -1,20 +1,21 @@
 generate_api = [python, files('generate.py')]
 
-core_vapi = join_paths(core_build_dir, 'frida-core.vapi')
-core_header = join_paths(core_build_dir, 'frida-core.h')
-base_vapi = join_paths(base_build_dir, f'frida-base-@api_version@.vapi')
-base_header = join_paths(base_build_dir, 'frida-base.h')
+generate_api_args = [
+  api_version,
+  core_build_dir / 'frida-core.vapi',
+  core_build_dir / 'frida-core.h',
+  base_build_dir / f'frida-base-@api_version@.vapi',
+  base_build_dir / 'frida-base.h',
+  meson.current_build_dir(),
+]
 
 core_public_h = custom_target('frida-core-header',
   input: [core, base],
   output: ['frida-core.h'],
   command: [
     generate_api,
     '--output=header',
-    api_version,
-    core_vapi, core_header,
-    base_vapi, base_header,
-    meson.current_build_dir(),
+    generate_api_args,
   ],
   install: true,
   install_dir: header_install_dir,
@@ -23,24 +24,21 @@ core_public_h = custom_target('frida-core-header',
 core_public_vapi = custom_target('frida-core-vapi',
   input: [core, base],
   output: [
-    'frida-core-@0@.vapi'.format(api_version),
-    'frida-core-@0@.deps'.format(api_version)
+    f'frida-core-@api_version@.vapi',
+    f'frida-core-@api_version@.deps',
   ],
   command: [
     generate_api,
     '--output=vapi',
-    api_version,
-    core_vapi, core_header,
-    base_vapi, base_header,
-    meson.current_build_dir(),
+    generate_api_args,
   ],
   install: true,
-  install_dir: join_paths(get_option('datadir'), 'vala', 'vapi'),
+  install_dir: get_option('datadir') / 'vala' / 'vapi',
 )
 
 core_public_lib = custom_target('frida-core-library',
   input: [core] + internal_libs,
-  output: 'libfrida-core-@0@.a'.format(api_version),
+  output: f'libfrida-core-@api_version@.a',
   command: [
     python,
     files('merge.py'),
@@ -81,13 +79,13 @@ endif
 
 pkg = import('pkgconfig')
 pkg.generate(
-  filebase: 'frida-core-' + api_version,
+  filebase: f'frida-core-@api_version@',
   name: 'Frida Core',
   version: meson.project_version(),
   description: 'Frida core library intended for static linking into bindings',
   requires: ['glib-2.0', 'gobject-2.0', 'gio-2.0', 'json-glib-1.0'],
   requires_private: ['gmodule-2.0', 'gee-0.8', 'libsoup-3.0', 'frida-gum-1.0', 'frida-gumjs-inspector-1.0', 'libbrotlidec'] + backend_reqs_private,
-  subdirs: 'frida-' + api_version,
+  subdirs: f'frida-@api_version@',
   libraries: [core_public_lib],
   libraries_private: backend_libs_private,
   extra_cflags: ['-I${frida_includedir}'],
@@ -101,4 +99,4 @@ pkg.generate(
   },
 )
 
-meson.override_dependency('frida-core-' + api_version, core_public_dep)
+meson.override_dependency(f'frida-core-@api_version@', core_public_dep)

src/meson.build

@@ -134,7 +134,7 @@ if have_local_backend
       command: [
         resource_compiler_cmd_array,
         '-c', '@INPUT0@',
-        '-o', join_paths(meson.current_build_dir(), 'frida-data-darwin'),
+        '-o', meson.current_build_dir() / 'frida-data-darwin',
         '@INPUT1@',
         '@INPUT2@',
         '@INPUT3@',
@@ -268,7 +268,7 @@ if have_local_backend
         command: [
           resource_compiler_cmd_array,
           '-c', '@INPUT0@',
-          '-o', join_paths(meson.current_build_dir(), 'frida-data-android'),
+          '-o', meson.current_build_dir() / 'frida-data-android',
           '@INPUT1@',
         ],
       )
@@ -308,7 +308,7 @@ if have_local_backend
       command: [
         resource_compiler_cmd_array,
         '-c', '@INPUT0@',
-        '-o', join_paths(meson.current_build_dir(), 'frida-data-helper-backend'),
+        '-o', meson.current_build_dir() / 'frida-data-helper-backend',
         '@INPUT1@',
         '@INPUT2@',
       ],
@@ -342,7 +342,7 @@ if have_local_backend
       'linux' / 'frida-helper-service.vala',
     ]
     helper_symscript = 'linux' / 'frida-helper.version'
-    helper_link_args = ['-Wl,--version-script,' + join_paths(meson.current_source_dir(), helper_symscript)]
+    helper_link_args = ['-Wl,--version-script,' + meson.current_source_dir() / helper_symscript]
     helper_link_depends = [helper_symscript]
     raw_helper = executable('frida-helper-raw', helper_sources,
       vala_args: helper_backend_vala_args,