Remove python_selector.py in favor of run_python.sh

ChangeLog.md

@@ -17,6 +17,11 @@ See docs/process.md for how version tagging works.
 
 Current Trunk
 -------------
+- Program entry points without extensions are now shell scripts rather than
+  python programs. See #10729.  This means that `python emcc` no longer works.
+  However `emcc`, `emcc.py` and `python emcc.py` all continue to work.
+  The reason for this change is that `#!/usr/bin/env python` is no longer
+  portable since the python symlink was dropped from Ubuntu 20.04.
 
 v1.39.11: 03/20/2020
 --------------------
@@ -27,7 +32,7 @@ v1.39.11: 03/20/2020
   https://libbsd.freedesktop.org/.
 - Change the meaning of `ASYNCIFY_IMPORTS`: it now contains only new imports
   you add, and does not need to contain the list of default system imports like
-  ``emscripten_sleep``. There is no harm in providing them, though, so this
+  `emscripten_sleep`. There is no harm in providing them, though, so this
   is not a breaking change.
 - Enable DWARF support: When compiling with `-g`, normal DWARF emitting happens,
   and when linking with `-g` we preserve that and update it. This is a change

em++

@@ -0,0 +1 @@
+tools/run_python.sh

em++.py

@@ -1,19 +1,17 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # Copyright 2011 The Emscripten Authors.  All rights reserved.
 # Emscripten is available under two separate licenses, the MIT license and the
 # University of Illinois/NCSA Open Source License.  Both these licenses can be
 # found in the LICENSE file.
 
-# This script should work in python 2 *or* 3. It loads the main code using
-# python_selector, which may pick a different version.
-# It also tells emcc.py that we want C++ and not C by default
-
-import os
 import sys
-from tools import python_selector
+import emcc
 
 sys.argv += ['--emscripten-cxx']
 
-emcc = os.path.join(os.path.dirname(os.path.realpath(__file__)), 'emcc')
 if __name__ == '__main__':
-  python_selector.run(emcc)
+  try:
+    sys.exit(emcc.run(sys.argv))
+  except KeyboardInterrupt:
+    emcc.logger.warning('KeyboardInterrupt')
+    sys.exit(1)

emar

@@ -0,0 +1 @@
+tools/run_python.sh

emcc

@@ -0,0 +1 @@
+tools/run_python.sh

emcmake

@@ -0,0 +1 @@
+tools/run_python.sh

emconfigure

@@ -0,0 +1 @@
+tools/run_python.sh

emmake

@@ -0,0 +1 @@
+tools/run_python.sh

emranlib

@@ -0,0 +1 @@
+tools/run_python.sh

emrun

@@ -0,0 +1 @@
+tools/run_python.sh

emscons

@@ -0,0 +1 @@
+tools/run_python.sh

tests/test_browser.py

@@ -2464,12 +2464,12 @@ def test_mmap_file(self):
   def test_emrun_info(self):
     if not has_browser():
       self.skipTest('need a browser')
-    result = run_process([PYTHON, path_from_root('emrun'), '--system_info', '--browser_info'], stdout=PIPE).stdout
+    result = run_process([PYTHON, path_from_root('emrun.py'), '--system_info', '--browser_info'], stdout=PIPE).stdout
     assert 'CPU' in result
     assert 'Browser' in result
     assert 'Traceback' not in result
 
-    result = run_process([PYTHON, path_from_root('emrun'), '--list_browsers'], stdout=PIPE).stdout
+    result = run_process([PYTHON, path_from_root('emrun.py'), '--list_browsers'], stdout=PIPE).stdout
     assert 'Traceback' not in result
 
   # Deliberately named as test_zzz_emrun to make this test the last one
@@ -2484,7 +2484,7 @@ def test_zzz_emrun(self):
     # and the browser will not close as part of the test, pinning down the cwd on Windows and it wouldn't be possible to delete it. Therefore switch away from that directory
     # before launching.
     os.chdir(path_from_root())
-    args_base = [PYTHON, path_from_root('emrun'), '--timeout', '30', '--safe_firefox_profile', '--kill_exit', '--port', '6939', '--verbose', '--log_stdout', os.path.join(outdir, 'stdout.txt'), '--log_stderr', os.path.join(outdir, 'stderr.txt')]
+    args_base = [PYTHON, path_from_root('emrun.py'), '--timeout', '30', '--safe_firefox_profile', '--kill_exit', '--port', '6939', '--verbose', '--log_stdout', os.path.join(outdir, 'stdout.txt'), '--log_stderr', os.path.join(outdir, 'stderr.txt')]
     if EMTEST_BROWSER is not None:
       # If EMTEST_BROWSER carried command line arguments to pass to the browser,
       # (e.g. "firefox -profile /path/to/foo") those can't be passed via emrun,

tests/test_other.py

@@ -6094,27 +6094,27 @@ def check(what, args, fail=True, expect=''):
       assert ('is a helper for' in output.stderr) == fail
       assert ('Typical usage' in output.stderr) == fail
       self.assertContained(expect, output.stdout)
-    check('emmake', [])
-    check('emconfigure', [])
-    check('emmake', ['--version'])
-    check('emconfigure', ['--version'])
-    check('emmake', ['make'], fail=False)
-    check('emconfigure', ['configure'], fail=False)
-    check('emconfigure', ['./configure'], fail=False)
-    check('emcmake', ['cmake'], fail=False)
+    check('emmake.py', [])
+    check('emconfigure.py', [])
+    check('emmake.py', ['--version'])
+    check('emconfigure.py', ['--version'])
+    check('emmake.py', ['make'], fail=False)
+    check('emconfigure.py', ['configure'], fail=False)
+    check('emconfigure.py', ['./configure'], fail=False)
+    check('emcmake.py', ['cmake'], fail=False)
 
     create_test_file('test.py', '''
 import os
 print(os.environ.get('CROSS_COMPILE'))
 ''')
-    check('emconfigure', [PYTHON, 'test.py'], expect=path_from_root('em'), fail=False)
-    check('emmake', [PYTHON, 'test.py'], expect=path_from_root('em'), fail=False)
+    check('emconfigure.py', [PYTHON, 'test.py'], expect=path_from_root('em'), fail=False)
+    check('emmake.py', [PYTHON, 'test.py'], expect=path_from_root('em'), fail=False)
 
     create_test_file('test.py', '''
 import os
 print(os.environ.get('NM'))
 ''')
-    check('emconfigure', [PYTHON, 'test.py'], expect=shared.LLVM_NM, fail=False)
+    check('emconfigure.py', [PYTHON, 'test.py'], expect=shared.LLVM_NM, fail=False)
 
   @no_windows('This test is broken, https://github.com/emscripten-core/emscripten/issues/8872')
   def test_emmake_python(self):
@@ -6135,7 +6135,7 @@ def test_sdl2_config(self):
       out = run_process([PYTHON, path_from_root('system', 'bin', 'sdl2-config')] + args, stdout=PIPE, stderr=PIPE).stdout
       assert expected in out, out
       print('via emmake')
-      out = run_process([PYTHON, path_from_root('emmake'), 'sdl2-config'] + args, stdout=PIPE, stderr=PIPE).stdout
+      out = run_process([PYTHON, path_from_root('emmake.py'), 'sdl2-config'] + args, stdout=PIPE, stderr=PIPE).stdout
       assert expected in out, out
 
   def test_module_onexit(self):
@@ -7253,10 +7253,6 @@ def run(python):
         has = Building.which(python) is not None
       print(python, has)
       if has:
-        print('  checking emcc...')
-        run_process([python, trim_py_suffix(EMCC), '--version'], stdout=PIPE)
-        print('  checking em++...')
-        run_process([python, trim_py_suffix(EMXX), '--version'], stdout=PIPE)
         print('  checking emcc.py...')
         run_process([python, EMCC, '--version'], stdout=PIPE)
         print('  checking em++.py...')

tests/test_sockets.py

@@ -284,8 +284,8 @@ def test_enet(self):
     shared.try_delete('enet')
     shutil.copytree(path_from_root('tests', 'enet'), 'enet')
     with chdir('enet'):
-      run_process([PYTHON, path_from_root('emconfigure'), './configure'])
-      run_process([PYTHON, path_from_root('emmake'), 'make'])
+      run_process([PYTHON, path_from_root('emconfigure.py'), './configure'])
+      run_process([PYTHON, path_from_root('emmake.py'), 'make'])
       enet = [self.in_dir('enet', '.libs', 'libenet.a'), '-I' + path_from_root('tests', 'enet', 'include')]
 
     for harness in [

tools/emdump

@@ -0,0 +1 @@
+run_python.sh

tools/run_python.sh

@@ -0,0 +1,26 @@
+#!/bin/sh
+# Copyright 2011 The Emscripten Authors.  All rights reserved.
+# Emscripten is available under two separate licenses, the MIT license and the
+# University of Illinois/NCSA Open Source License.  Both these licenses can be
+# found in the LICENSE file.
+#
+# Entpy point for running python scripts on UNIX systems.
+
+if [ -z $PYTHON ]; then
+  PYTHON=$(which python3)
+fi
+
+if [ -z $PYTHON ]; then
+  PYTHON=$(which python)
+fi
+
+if [ -z $PYTHON ]; then
+  PYTHON=$(which python2)
+fi
+
+if [ -z $PYTHON ]; then
+  print 'unable to find python in $PATH'
+  exit 1
+fi
+
+exec $PYTHON "$0.py" "$@"

tools/shared.py

@@ -710,7 +710,7 @@ def replace_or_append_suffix(filename, new_suffix):
 EMCC = path_from_root('emcc.py')
 EMXX = path_from_root('em++.py')
 EMAR = path_from_root('emar.py')
-EMRANLIB = path_from_root('emranlib')
+EMRANLIB = path_from_root('emranlib.py')
 EMCONFIG = path_from_root('em-config')
 EMLINK = path_from_root('emlink.py')
 EMCONFIGURE = path_from_root('emconfigure.py')
@@ -1538,9 +1538,7 @@ def nop(arg):
     # not to, as some configure scripts expect e.g. CC to be a literal executable
     # (but "python emcc.py" is not a file that exists).
     # note that we point to emcc etc. here, without a suffix, instead of to
-    # emcc.py etc. The unsuffixed versions have the python_selector logic that can
-    # pick the right version as needed (which is not crucial right now as we support
-    # both 2 and 3, but eventually we may be 3-only).
+    # emcc.py etc.
     env['CC'] = quote(unsuffixed(EMCC)) if not WINDOWS else 'python %s' % quote(EMCC)
     env['CXX'] = quote(unsuffixed(EMXX)) if not WINDOWS else 'python %s' % quote(EMXX)
     env['AR'] = quote(unsuffixed(EMAR)) if not WINDOWS else 'python %s' % quote(EMAR)