Move chdir contextmanager to utils.py. NFC. (#13091)

tests/runner.py

@@ -226,17 +226,6 @@ def with_env_modify(updates):
   return decorated
 
 
-@contextlib.contextmanager
-def chdir(dir):
-  """A context manager that performs actions in the given directory."""
-  orig_cwd = os.getcwd()
-  os.chdir(dir)
-  try:
-    yield
-  finally:
-    os.chdir(orig_cwd)
-
-
 def ensure_dir(dirname):
   if not os.path.isdir(dirname):
     os.makedirs(dirname)

tests/test_other.py

@@ -32,7 +32,7 @@ from tools.shared import try_delete, config
 from tools.shared import EMCC, EMXX, EMAR, EMRANLIB, PYTHON, FILE_PACKAGER, WINDOWS, EM_BUILD_VERBOSE
 from tools.shared import CLANG_CC, CLANG_CXX, LLVM_AR, LLVM_DWARFDUMP
 from runner import RunnerCore, path_from_root, is_slow_test, ensure_dir, disabled, make_executable
-from runner import env_modify, no_mac, no_windows, requires_native_clang, chdir, with_env_modify
+from runner import env_modify, no_mac, no_windows, requires_native_clang, with_env_modify
 from runner import create_test_file, parameterized, NON_ZERO, node_pthreads
 from tools import shared, building, utils
 import jsrun
@@ -2014,7 +2014,7 @@ int f() {
     # this test copies the site_scons directory alongside the test
     shutil.copytree(path_from_root('tests', 'scons'), 'test')
     shutil.copytree(path_from_root('tools', 'scons', 'site_scons'), os.path.join('test', 'site_scons'))
-    with chdir('test'):
+    with utils.chdir('test'):
       self.run_process(['scons'])
       output = self.run_js('scons_integration.js', assert_returncode=5)
     self.assertContained('If you see this - the world is all right!', output)
@@ -2026,7 +2026,7 @@ int f() {
     # uses the emscons wrapper which requires EMSCRIPTEN_TOOLPATH to find
     # site_scons
     shutil.copytree(path_from_root('tests', 'scons'), 'test')
-    with chdir('test'):
+    with utils.chdir('test'):
       self.run_process([path_from_root('emscons'), 'scons'])
       output = self.run_js('scons_integration.js', assert_returncode=5)
     self.assertContained('If you see this - the world is all right!', output)

tests/test_sanity.py

@@ -12,14 +12,14 @@ import tempfile
 import zipfile
 from subprocess import PIPE, STDOUT
 
-from runner import RunnerCore, path_from_root, env_modify, chdir
+from runner import RunnerCore, path_from_root, env_modify
 from runner import create_test_file, ensure_dir, make_executable
 from tools.config import config_file, EM_CONFIG
 from tools.shared import PYTHON, EMCC
 from tools.shared import CANONICAL_TEMP_DIR
 from tools.shared import try_delete, config
 from tools.shared import EXPECTED_LLVM_VERSION, Cache
-from tools import shared, system_libs
+from tools import shared, system_libs, utils
 
 SANITY_FILE = shared.Cache.get_path('sanity.txt', root=True)
 commands = [[EMCC], [PYTHON, path_from_root('tests', 'runner.py'), 'blahblah']]
@@ -521,7 +521,7 @@ fi
 
     temp_dir = tempfile.mkdtemp(prefix='emscripten_temp_')
 
-    with chdir(temp_dir):
+    with utils.chdir(temp_dir):
       self.run_process([EMCC, '--em-config', custom_config_filename] + MINIMAL_HELLO_WORLD + ['-O2'])
       result = self.run_js('a.out.js')
 

tests/test_sockets.py

@@ -24,8 +24,8 @@ except Exception:
   # which is the same behavior as before.
   pass
 import clang_native
-from runner import BrowserCore, no_windows, chdir, create_test_file
-from tools import shared, config
+from runner import BrowserCore, no_windows, create_test_file
+from tools import shared, config, utils
 from tools.shared import PYTHON, EMCC, path_from_root, WINDOWS, run_process, CLANG_CC
 
 npm_checked = False
@@ -286,7 +286,7 @@ class sockets(BrowserCore):
     # this is also a good test of raw usage of emconfigure and emmake
     shared.try_delete('enet')
     shutil.copytree(path_from_root('tests', 'third_party', 'enet'), 'enet')
-    with chdir('enet'):
+    with utils.chdir('enet'):
       self.run_process([path_from_root('emconfigure'), './configure'])
       self.run_process([path_from_root('emmake'), 'make'])
       enet = [self.in_dir('enet', '.libs', 'libenet.a'), '-I' + self.in_dir('enet', 'include')]

tools/system_libs.py

@@ -15,7 +15,7 @@ import tarfile
 import zipfile
 from glob import iglob
 
-from . import shared, building, ports, config
+from . import shared, building, ports, config, utils
 from . import deps_info
 from tools.shared import mangle_c_symbol_name, demangle_c_symbol_name
 
@@ -1816,12 +1816,8 @@ class Ports(object):
         z = tarfile.open(fullpath, 'r:gz')
       else:
         z = zipfile.ZipFile(fullpath, 'r')
-      try:
-        cwd = os.getcwd()
-        os.chdir(fullname)
+      with utils.chdir(fullname):
         z.extractall()
-      finally:
-        os.chdir(cwd)
 
       State.unpacked = True
 

tools/utils.py

@@ -3,6 +3,7 @@
 # University of Illinois/NCSA Open Source License.  Both these licenses can be
 # found in the LICENSE file.
 
+import contextlib
 import os
 import sys
 
@@ -32,6 +33,17 @@ def safe_ensure_dirs(dirname):
       raise
 
 
+@contextlib.contextmanager
+def chdir(dir):
+  """A context manager that performs actions in the given directory."""
+  orig_cwd = os.getcwd()
+  os.chdir(dir)
+  try:
+    yield
+  finally:
+    os.chdir(orig_cwd)
+
+
 # Finds the given executable 'program' in PATH. Operates like the Unix tool 'which'.
 def which(program):
   def is_exe(fpath):