Add is_slow_test test decorator and EMTEST_SKIP_SLOW env var (#7642)

List of slow tests based on Jacob's list.  I only included tests
that take more than 20 seconds.

Future work:
- Warn if test marked as slow runs in <10 seconds.
- Warn if test not marked as slow runs in >30 seconds.

Author: sbc100

tests/runner.py

@@ -91,6 +91,8 @@ def path_from_root(*pathelems):
 # to force testing on all js engines, good to find js engine bugs
 EMTEST_ALL_ENGINES = os.getenv('EMTEST_ALL_ENGINES')
 
+EMTEST_SKIP_SLOW = os.getenv('EMTEST_SKIP_SLOW')
+
 
 # checks if browser testing is enabled
 def has_browser():
@@ -118,6 +120,15 @@ def decorated(self):
   return decorated
 
 
+def is_slow_test(func):
+  def decorated(self, *args, **kwargs):
+    if EMTEST_SKIP_SLOW:
+      return self.skipTest('skipping slow tests')
+    return func(self, *args, **kwargs)
+
+  return decorated
+
+
 def no_wasm_backend(note=''):
   def decorated(f):
     return skip_if(f, 'is_wasm_backend', note)

tests/test_core.py

@@ -23,7 +23,7 @@
 from tools.shared import NODE_JS, V8_ENGINE, JS_ENGINES, SPIDERMONKEY_ENGINE, PYTHON, EMCC, EMAR, CLANG, WINDOWS, AUTODEBUGGER
 from tools import jsrun, shared
 from runner import RunnerCore, path_from_root, core_test_modes, get_bullet_library, get_freetype_library, get_poppler_library
-from runner import skip_if, no_wasm_backend, needs_dlfcn, no_windows, env_modify, with_env_modify
+from runner import skip_if, no_wasm_backend, needs_dlfcn, no_windows, env_modify, with_env_modify, is_slow_test
 
 # decorators for limiting which modes a test can run in
 
@@ -1878,6 +1878,7 @@ def test_bigswitch(self):
 ''', args=['34962', '26214', '35040', str(0xbf4)])
 
   @no_emterpreter
+  @is_slow_test
   def test_biggerswitch(self):
     num_cases = 20000
     switch_case = run_process([PYTHON, path_from_root('tests', 'gen_large_switchcase.py'), str(num_cases)], stdout=PIPE, stderr=PIPE).stdout
@@ -4831,6 +4832,7 @@ def test_fs_base(self):
     self.do_run(src, expected)
 
   @also_with_noderawfs
+  @is_slow_test
   def test_fs_nodefs_rw(self, js_engines=[NODE_JS]):
     self.set_setting('SYSCALL_DEBUG', 1)
     src = open(path_from_root('tests', 'fs', 'test_nodefs_rw.c'), 'r').read()
@@ -5823,6 +5825,7 @@ def test_lua(self):
                   output_nicerizer=lambda string, err: (string + err).replace('\n\n', '\n').replace('\n\n', '\n'))
 
   @no_windows('./configure scripts dont to run on windows.')
+  @is_slow_test
   def test_freetype(self):
     assert 'asm2g' in core_test_modes
     if self.run_name == 'asm2g':
@@ -5895,6 +5898,7 @@ def test_sqlite(self):
                 includes=[path_from_root('tests', 'sqlite')],
                 force_c=True)
 
+  @is_slow_test
   def test_zlib(self):
     self.maybe_closure()
 
@@ -5916,6 +5920,7 @@ def test_zlib(self):
                 includes=[path_from_root('tests', 'zlib'), os.path.join(self.get_dir(), 'building', 'zlib')],
                 force_c=True)
 
+  @is_slow_test
   def test_the_bullet(self): # Called thus so it runs late in the alphabetical cycle... it is long
     self.set_setting('DEAD_FUNCTIONS', ['__ZSt9terminatev'])
 
@@ -5986,6 +5991,7 @@ def test():
       # Make sure that DFE ends up eliminating more than 200 functions (if we can view source)
       assert (num_original_funcs - self.count_funcs('src.cpp.o.js')) > 200
 
+  @is_slow_test
   def test_openjpeg(self):
     # remove -g, so we have one test without it by default
     Building.COMPILER_TEST_OPTS = [x for x in Building.COMPILER_TEST_OPTS if x != '-g']
@@ -6104,6 +6110,7 @@ def test_lifetime(self):
   # They are only valid enough for us to read for test purposes, not for llvm-as
   # to process.
   @no_wasm_backend("uses bitcode compiled with asmjs, and we don't have unified triples")
+  @is_slow_test
   def test_cases(self):
     if Building.LLVM_OPTS:
       self.skipTest("Our code is not exactly 'normal' llvm assembly")
@@ -6208,6 +6215,7 @@ def test_cases(self):
         generated = open('src.cpp.o.js').read() # noqa
         exec(open(src_checker).read())
 
+  @is_slow_test
   def test_fuzz(self):
     Building.COMPILER_TEST_OPTS += ['-I' + path_from_root('tests', 'fuzz', 'include'), '-w']
     # some of these tests - 2.c', '9.c', '19.c', '21.c', '20.cpp' - div or rem i32 by 0, which traps in wasm