[test] Add EMTEST_SKIP_NETWORK_TESTS (#21380)

I was doing some work on an airplane over the weekend and I found this
useful.

test/common.py

@@ -93,6 +93,9 @@
   config.NODE_JS_TEST = config.NODE_JS
 
 
+requires_network = unittest.skipIf(os.getenv('EMTEST_SKIP_NETWORK_TESTS'), 'This test requires network access')
+
+
 def test_file(*path_components):
   """Construct a path relative to the emscripten "tests" directory."""
   return str(Path(TEST_ROOT, *path_components))

test/test_other.py

@@ -37,6 +37,7 @@
 from common import requires_wasm_eh, crossplatform, with_both_sjlj, also_with_standalone_wasm
 from common import also_with_minimal_runtime, also_with_wasm_bigint, also_with_wasm64, flaky
 from common import EMTEST_BUILD_VERBOSE, PYTHON, WEBIDL_BINDER
+from common import requires_network
 from tools import shared, building, utils, response_file, cache
 from tools.utils import read_file, write_file, delete_file, read_binary
 import common
@@ -1001,6 +1002,7 @@ def test_cmake_emscripten_system_processor(self):
       [EMCMAKE, 'cmake', cmake_dir, '-DEMSCRIPTEN_SYSTEM_PROCESSOR=arm'], stdout=PIPE).stdout
     self.assertContained('CMAKE_SYSTEM_PROCESSOR is arm', out)
 
+  @requires_network
   def test_cmake_find_stuff(self):
     # Ensure that zlib exists in the sysroot
     self.run_process([EMCC, test_file('hello_world.c'), '-sUSE_ZLIB'])
@@ -1021,6 +1023,7 @@ def test_cmake_install(self):
     self.assertContained('foo: 42\n', self.run_js('build2/Bar.js'))
     self.run_process(['cmake', '--build', 'build2', '--target', 'install'])
 
+  @requires_network
   def test_cmake_find_modules(self):
     self.run_process([EMCMAKE, 'cmake', test_file('cmake/find_modules')])
     self.run_process(['cmake', '--build', '.'])
@@ -2276,6 +2279,7 @@ def test_sdl_scan_code_from_key(self):
     ''')
     self.do_runf('main.c', '204\n')
 
+  @requires_network
   def test_sdl2_mixer_wav(self):
     self.emcc(test_file('browser/test_sdl2_mixer_wav.c'), ['-sUSE_SDL_MIXER=2'], output_filename='a.out.js')
     self.emcc(test_file('browser/test_sdl2_mixer_wav.c'), ['--use-port=sdl2_mixer'], output_filename='a.out.js')
@@ -2286,11 +2290,13 @@ def test_sdl2_linkable(self):
     self.emcc(test_file('browser/test_sdl2_misc.c'), ['-sLINKABLE', '-sUSE_SDL=2'], output_filename='a.out.js')
     self.emcc(test_file('browser/test_sdl2_misc.c'), ['-sLINKABLE', '--use-port=sdl2'], output_filename='a.out.js')
 
+  @requires_network
   def test_sdl2_gfx_linkable(self):
     # Same as above but for sdl2_gfx library
     self.emcc(test_file('browser/test_sdl2_misc.c'), ['-Wl,-fatal-warnings', '-sLINKABLE', '-sUSE_SDL_GFX=2'], output_filename='a.out.js')
     self.emcc(test_file('browser/test_sdl2_misc.c'), ['-Wl,-fatal-warnings', '-sLINKABLE', '--use-port=sdl2_gfx'], output_filename='a.out.js')
 
+  @requires_network
   def test_libpng(self):
     shutil.copyfile(test_file('third_party/libpng/pngtest.png'), 'pngtest.png')
     self.do_runf('third_party/libpng/pngtest.c', 'libpng passes test',
@@ -2299,11 +2305,13 @@ def test_libpng(self):
                  emcc_args=['--embed-file', 'pngtest.png', '--use-port=libpng'])
 
   @node_pthreads
+  @requires_network
   def test_libpng_with_pthreads(self):
     shutil.copyfile(test_file('third_party/libpng/pngtest.png'), 'pngtest.png')
     self.do_runf('third_party/libpng/pngtest.c', 'libpng passes test',
                  emcc_args=['--embed-file', 'pngtest.png', '-sUSE_LIBPNG', '-pthread'])
 
+  @requires_network
   def test_giflib(self):
     # giftext.c contains a sprintf warning
     self.emcc_args += ['-Wno-fortify-source']
@@ -2322,6 +2330,7 @@ def test_giflib(self):
                  emcc_args=['--embed-file', 'treescap.gif', '--use-port=giflib'],
                  args=['treescap.gif'])
 
+  @requires_network
   def test_libjpeg(self):
     shutil.copyfile(test_file('screenshot.jpg'), 'screenshot.jpg')
     self.do_runf('jpeg_test.c', 'Image is 600 by 450 with 3 components',
@@ -2331,22 +2340,26 @@ def test_libjpeg(self):
                  emcc_args=['--embed-file', 'screenshot.jpg', '--use-port=libjpeg'],
                  args=['screenshot.jpg'])
 
+  @requires_network
   def test_bullet(self):
     self.do_runf('bullet_hello_world.cpp', 'BULLET RUNNING', emcc_args=['-sUSE_BULLET'])
     self.do_runf('bullet_hello_world.cpp', 'BULLET RUNNING', emcc_args=['--use-port=bullet'])
 
+  @requires_network
   def test_vorbis(self):
     # This will also test if ogg compiles, because vorbis depends on ogg
     self.do_runf('vorbis_test.c', 'ALL OK', emcc_args=['-sUSE_VORBIS'])
     self.do_runf('vorbis_test.c', 'ALL OK', emcc_args=['--use-port=vorbis'])
 
+  @requires_network
   def test_bzip2(self):
     self.do_runf('bzip2_test.c', 'usage: unzcrash filename',
                  emcc_args=['-sUSE_BZIP2', '-Wno-pointer-sign'])
     self.do_runf('bzip2_test.c', 'usage: unzcrash filename',
                  emcc_args=['--use-port=bzip2', '-Wno-pointer-sign'])
 
   @with_both_sjlj
+  @requires_network
   def test_freetype(self):
     # copy the Liberation Sans Bold truetype file located in the
     # <emscripten_root>/test/freetype to the compilation folder
@@ -2375,19 +2388,24 @@ def test_freetype(self):
     self.do_runf('freetype_test.c', expectedOutput,
                  emcc_args=['--use-port=freetype', '--embed-file', 'LiberationSansBold.ttf'])
 
+  @requires_network
+  @requires_network
   def test_freetype_with_pthreads(self):
     # Verify that freetype supports compilation requiring pthreads
     self.emcc(test_file('freetype_test.c'), ['-pthread', '-sUSE_FREETYPE'], output_filename='a.out.js')
 
+  @requires_network
   def test_icu(self):
     self.set_setting('USE_ICU')
     self.do_runf('other/test_icu.cpp')
 
+  @requires_network
   def test_sdl2_ttf(self):
     # This is a compile-only to test to verify that sdl2-ttf (and freetype and harfbuzz) are buildable.
     self.emcc(test_file('browser/test_sdl2_ttf.c'), args=['-sUSE_SDL=2', '-sUSE_SDL_TTF=2'], output_filename='a.out.js')
     self.emcc(test_file('browser/test_sdl2_ttf.c'), args=['--use-port=sdl2', '--use-port=sdl2_ttf'], output_filename='a.out.js')
 
+  @requires_network
   def test_contrib_ports(self):
     # Verify that contrib ports can be used (using the only contrib port available ATM, but can be replaced
     # with a different contrib port when there is another one
@@ -2401,6 +2419,7 @@ def test_external_ports_simple(self):
     self.do_runf('other/test_external_ports_simple.c', emcc_args=[f'--use-port={simple_port_path}'])
 
   @crossplatform
+  @requires_network
   def test_external_ports(self):
     if config.FROZEN_CACHE:
       self.skipTest("test doesn't work with frozen cache")