[build-script] Provide centralized command line and file system interface for build-script.

Author: rintaro

utils/build-script

@@ -18,7 +18,6 @@ import pipes
 import platform
 import re
 import shlex
-import shutil
 import sys
 
 # FIXME: Instead of modifying the system path in order to enable imports from
@@ -31,7 +30,6 @@ from SwiftBuildSupport import (
     HOME,
     SWIFT_BUILD_ROOT,
     SWIFT_SOURCE_ROOT,
-    WorkingDirectory,
     check_call,
     get_all_preset_names,
     get_preset_options,
@@ -45,6 +43,7 @@ sys.path.append(os.path.join(os.path.dirname(__file__), 'swift_build_support'))
 from swift_build_support.toolchain import host_toolchain  # noqa (E402)
 import swift_build_support.debug      # noqa (E402)
 from swift_build_support import migration  # noqa (E402)
+from swift_build_support import shell  # noqa (E402)
 import swift_build_support.tar        # noqa (E402)
 import swift_build_support.targets    # noqa (E402)
 from swift_build_support.cmake import CMake  # noqa (E402)
@@ -1200,8 +1199,9 @@ details of the setups of other systems or automated environments.""")
         source_root=SWIFT_SOURCE_ROOT,
         build_root=os.path.join(SWIFT_BUILD_ROOT, args.build_subdir))
 
-    if args.clean and os.path.isdir(workspace.build_root):
-        shutil.rmtree(workspace.build_root)
+    # Clean build_dir if requested.
+    if args.clean:
+        shell.rmtree(workspace.build_root)
 
     cmake = CMake(args=args,
                   toolchain=toolchain)
@@ -1411,7 +1411,7 @@ details of the setups of other systems or automated environments.""")
         # it is archiving. To stay safe, we change working directories, then
         # run `tar` without the leading '/' (we remove it ourselves to keep
         # `tar` from emitting a warning).
-        with WorkingDirectory(args.install_symroot):
+        with shell.pushd(args.install_symroot):
             swift_build_support.tar.tar(source=prefix.lstrip('/'),
                                         destination=args.symbols_package)
 

utils/swift_build_support/swift_build_support/shell.py

@@ -0,0 +1,98 @@
+# swift_build_support/shell.py ----------------------------------*- python -*-
+#
+# This source file is part of the Swift.org open source project
+#
+# Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
+# Licensed under Apache License v2.0 with Runtime Library Exception
+#
+# See http://swift.org/LICENSE.txt for license information
+# See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+# ----------------------------------------------------------------------------
+"""
+Centralized command line and file system interface for the build script.
+"""
+# ----------------------------------------------------------------------------
+
+from __future__ import print_function
+
+import os
+import shutil
+import subprocess
+import sys
+import pipes
+from contextlib import contextmanager
+
+dry_run = False
+
+
+def _quote(arg):
+    return pipes.quote(str(arg))
+
+
+def _coerce_dry_run(dry_run_override):
+    if dry_run_override is None:
+        return dry_run
+    else:
+        return dry_run_override
+
+
+def _print_command(dry_run, command, env=None, prompt="+ "):
+    output = []
+    if env is not None:
+        output += ['env'] + [_quote("%s=%s" % (k, v)) for k, v in env]
+    output += [_quote(arg) for arg in command]
+    file = None
+    if not dry_run:
+        file = sys.stderr
+    print(prompt + ' '.join(output), file=file)
+
+
+def call(command, stderr=None, env=None, dry_run=None):
+    dry_run = _coerce_dry_run(dry_run)
+    _print_command(dry_run, command, env=env)
+    if dry_run:
+        return
+    _env = None
+    if env is not None:
+        _env = dict(os.environ)
+        _env.update(env)
+    subprocess.check_call(command, env=_env, stderr=stderr)
+
+
+@contextmanager
+def pushd(path, dry_run=None):
+    dry_run = _coerce_dry_run(dry_run)
+    old_dir = os.getcwd()
+    _print_command(dry_run, ["pushd", path])
+    if not dry_run:
+        os.chdir(path)
+    yield
+    _print_command(dry_run, ["popd"])
+    if not dry_run:
+        os.chdir(old_dir)
+
+
+def makedirs(path, dry_run=None):
+    dry_run = _coerce_dry_run(dry_run)
+    _print_command(dry_run, ['mkdir', '-p', path])
+    if dry_run:
+        return
+    if not os.path.isdir(path):
+        os.makedirs(path)
+
+
+def rmtree(path, dry_run=None):
+    dry_run = _coerce_dry_run(dry_run)
+    _print_command(dry_run, ['rm', '-rf', path])
+    if dry_run:
+        return
+    if os.path.exists(path):
+        shutil.rmtree(path)
+
+
+def copytree(src, dest, dry_run=None):
+    dry_run = _coerce_dry_run(dry_run)
+    _print_command(dry_run, ['cp', '-r', src, dest])
+    if dry_run:
+        return
+    shutil.copytree(src, dest)

utils/swift_build_support/swift_build_support/tar.py

@@ -8,9 +8,13 @@
 # See http://swift.org/LICENSE.txt for license information
 # See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
+from __future__ import absolute_import
+
 import platform
 import subprocess
 
+from . import shell
+
 
 def tar(source, destination):
     """
@@ -28,4 +32,4 @@ def tar(source, destination):
     # Capture stderr output such as 'tar: Failed to open ...'. We'll detect
     # these cases using the exit code, which should cause 'check_call' to
     # raise.
-    subprocess.check_call(args + [source], stderr=subprocess.PIPE)
+    shell.call(args + [source], stderr=subprocess.PIPE)

utils/swift_build_support/tests/test_shell.py

@@ -0,0 +1,152 @@
+# tests/test_shell.py -------------------------------------------*- python -*-
+#
+# This source file is part of the Swift.org open source project
+#
+# Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
+# Licensed under Apache License v2.0 with Runtime Library Exception
+#
+# See http://swift.org/LICENSE.txt for license information
+# See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+# ----------------------------------------------------------------------------
+
+import unittest
+import sys
+import os
+import os.path
+import shutil
+import tempfile
+try:
+    # py2
+    from StringIO import StringIO
+except ImportError:
+    # py3
+    from io import StringIO
+
+from swift_build_support import shell
+
+
+class ShellTestCase(unittest.TestCase):
+
+    def setUp(self):
+        self.tmpdir = os.path.realpath(tempfile.mkdtemp())
+        self._orig_stdout = sys.stdout
+        self._orig_stderr = sys.stderr
+        self.stdout = StringIO()
+        self.stderr = StringIO()
+        sys.stdout = self.stdout
+        sys.stderr = self.stderr
+
+    def tearDown(self):
+        sys.stdout = self._orig_stdout
+        sys.stderr = self._orig_stderr
+        if os.path.exists(self.tmpdir):
+            shutil.rmtree(self.tmpdir)
+
+    def test_call(self):
+        shell.dry_run = False
+        foo_file = os.path.join(self.tmpdir, 'foo.txt')
+        bar_file = os.path.join(self.tmpdir, 'bar.txt')
+
+        with open(foo_file, 'w') as f:
+            f.write("Hello Swift")
+
+        shell.call(['cp', foo_file, bar_file])
+
+        with open(bar_file, 'r') as f:
+            self.assertEqual(f.read(), "Hello Swift")
+
+        self.assertEqual(self.stdout.getvalue(), "")
+        self.assertEqual(self.stderr.getvalue(), '''\
++ cp {foo_file} {bar_file}
+'''.format(foo_file=foo_file, bar_file=bar_file))
+
+    def test_rmtree(self):
+        shell.dry_run = False
+        path = os.path.join(self.tmpdir, 'foo', 'bar')
+        shell.makedirs(path)
+
+        self.assertTrue(os.path.isdir(path))
+
+        shell.rmtree(os.path.join(path))
+        self.assertFalse(
+            os.path.exists(os.path.join(path)))
+        self.assertTrue(
+            os.path.exists(os.path.join(self.tmpdir, 'foo')))
+
+        self.assertEqual(self.stdout.getvalue(), "")
+        self.assertEqual(self.stderr.getvalue(), '''\
++ mkdir -p {path}
++ rm -rf {path}
+'''.format(path=path))
+
+    def test_pushd(self):
+        shell.dry_run = False
+        basedir = os.getcwd()
+
+        with shell.pushd(self.tmpdir):
+            self.assertEqual(os.getcwd(), self.tmpdir)
+        self.assertEqual(os.getcwd(), basedir)
+
+        # pushd inside pushd
+        with shell.pushd(self.tmpdir):
+            self.assertEqual(os.getcwd(), self.tmpdir)
+            shell.makedirs('foo')
+            with shell.pushd('foo'):
+                self.assertEqual(os.getcwd(),
+                                 os.path.join(self.tmpdir, 'foo'))
+            self.assertEqual(os.getcwd(), self.tmpdir)
+        self.assertEqual(os.getcwd(), basedir)
+
+        # cd inside pushd
+        with shell.pushd(self.tmpdir):
+            os.chdir('foo')
+            self.assertEqual(os.getcwd(), os.path.join(self.tmpdir, 'foo'))
+            os.chdir('..')
+            self.assertEqual(os.getcwd(), self.tmpdir)
+            shell.rmtree('foo')
+        self.assertEqual(os.getcwd(), basedir)
+
+        self.assertEqual(self.stdout.getvalue(), "")
+        self.assertEqual(self.stderr.getvalue(), '''\
++ pushd {tmpdir}
++ popd
++ pushd {tmpdir}
++ mkdir -p foo
++ pushd foo
++ popd
++ popd
++ pushd {tmpdir}
++ rm -rf foo
++ popd
+'''.format(tmpdir=self.tmpdir))
+
+    def test_dry_run(self):
+        shell.dry_run = True
+
+        basedir = os.getcwd()
+        foobar_dir = os.path.join(self.tmpdir, 'foo', 'bar')
+
+        shell.makedirs(foobar_dir)
+        self.assertFalse(os.path.exists(os.path.join(self.tmpdir, 'foo')))
+        self.assertFalse(os.path.exists(foobar_dir))
+
+        with shell.pushd(foobar_dir):
+            self.assertEqual(os.getcwd(), basedir)
+            shell.call(['touch', 'testfile'])
+            self.assertFalse(os.path.exists(
+                os.path.join(foobar_dir, 'testfile')))
+
+        self.assertEqual(os.getcwd(), basedir)
+
+        shell.rmtree(self.tmpdir)
+        self.assertTrue(os.path.exists(self.tmpdir))
+
+        self.assertEqual(self.stdout.getvalue(), '''\
++ mkdir -p {foobar_dir}
++ pushd {foobar_dir}
++ touch testfile
++ popd
++ rm -rf {tmpdir}
+'''.format(foobar_dir=foobar_dir, tmpdir=self.tmpdir))
+        self.assertEqual(self.stderr.getvalue(), "")
+        self.dry_run = False

utils/swift_build_support/tests/test_tar.py

@@ -9,21 +9,47 @@
 # See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
 
 import os
+import sys
 import subprocess
 import tempfile
 import unittest
+import platform
+try:
+    from StringIO import StringIO
+except ImportError:
+    from io import StringIO
 
 from swift_build_support.tar import tar
 
 
 class TarTestCase(unittest.TestCase):
+    def setUp(self):
+        self._orig_stdout = sys.stdout
+        self._orig_stderr = sys.stderr
+        self.stdout = StringIO()
+        self.stderr = StringIO()
+        sys.stdout = self.stdout
+        sys.stderr = self.stderr
+
+    def tearDown(self):
+        sys.stdout = self._orig_stdout
+        sys.stderr = self._orig_stderr
 
     def test_tar_this_file_succeeds(self):
         # `tar` complains about absolute paths, so use a relative path here.
         source = os.path.relpath(__file__)
         _, destination = tempfile.mkstemp()
         tar(source=source, destination=destination)
 
+        if platform.system() == "Darwin":
+            expect = "+ tar -c -z -f {dest} {source}\n"
+        else:
+            expect = "+ tar -c -z -f {dest} --owner=0 --group=0 {source}\n"
+
+        self.assertEqual(self.stdout.getvalue(), "")
+        self.assertEqual(self.stderr.getvalue(),
+                         expect.format(dest=destination, source=source))
+
     def test_tar_nonexistent_file_raises(self):
         with self.assertRaises(subprocess.CalledProcessError):
             tar(source='/path/to/something/that/surely/doesnt/exist',