Windows, Bazel client: pass Unix root as JVM flag

The Bazel client will pass the
--host_jvm_args=-Dbazel.windows_unix_root=<path>
flag to the server (computed from $BAZEL_SH), and
the server will no longer shell out to cygpath to
compute this value.

Fixes https://github.com/bazelbuild/bazel/issues/2983

Change-Id: Iacc2e2eb70eacafdf7bbcad68d375ba9eadc6ee1
PiperOrigin-RevId: 158830675

4 files changed, 113 insertions, 5 deletions

diff --git a/src/test/py/bazel/BUILD b/src/test/py/bazel/BUILD
index 428e97d629..32a5adda1e 100644
--- a/src/test/py/bazel/BUILD
+++ b/src/test/py/bazel/BUILD
@@ -32,3 +32,26 @@ py_test(
     srcs = ["bazel_clean_test.py"],
     deps = [":test_base"],
 )
+
+py_test(
+    name = "bazel_windows_test",
+    size = "medium",
+    srcs = select({
+        "//src:windows": ["bazel_windows_test.py"],
+        "//src:windows_msvc": ["bazel_windows_test.py"],
+        "//src:windows_msys": ["bazel_windows_test.py"],
+        "//conditions:default": ["empty_test.py"],
+    }),
+    main = select({
+        "//src:windows": "bazel_windows_test.py",
+        "//src:windows_msvc": "bazel_windows_test.py",
+        "//src:windows_msys": "bazel_windows_test.py",
+        "//conditions:default": "empty_test.py",
+    }),
+    deps = select({
+        "//src:windows": [":test_base"],
+        "//src:windows_msvc": [":test_base"],
+        "//src:windows_msys": [":test_base"],
+        "//conditions:default": [],
+    }),
+)
diff --git a/src/test/py/bazel/bazel_windows_test.py b/src/test/py/bazel/bazel_windows_test.py
new file mode 100644
index 0000000000..27bc37366c
--- /dev/null
+++ b/src/test/py/bazel/bazel_windows_test.py
@@ -0,0 +1,50 @@
+# Copyright 2017 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import unittest
+from src.test.py.bazel import test_base
+
+
+class BazelWindowsTest(test_base.TestBase):
+
+  def testWindowsUnixRoot(self):
+    self.ScratchFile('WORKSPACE')
+    self.ScratchFile('foo/BUILD', ['cc_binary(name="x", srcs=["x.cc"])'])
+    self.ScratchFile('foo/x.cc', [
+        '#include <stdio.h>', 'int main(int, char**) {'
+        '  printf("hello\\n");', '  return 0;', '}'
+    ])
+
+    exit_code, _, stderr = self.RunBazel(
+        ['--batch', 'build', '//foo:x', '--cpu=x64_windows_msys'],
+        env_remove={'BAZEL_SH'})
+    self.assertEqual(exit_code, 2)
+    self.assertIn('\'BAZEL_SH\' environment variable is not set',
+                  '\n'.join(stderr))
+
+    exit_code, _, stderr = self.RunBazel([
+        '--batch', '--host_jvm_args=-Dbazel.windows_unix_root=', 'build',
+        '//foo:x', '--cpu=x64_windows_msys'
+    ])
+    self.assertEqual(exit_code, 37)
+    self.assertIn('"bazel.windows_unix_root" JVM flag is not set',
+                  '\n'.join(stderr))
+
+    exit_code, _, _ = self.RunBazel(
+        ['--batch', 'build', '//foo:x', '--cpu=x64_windows_msys'])
+    self.assertEqual(exit_code, 0)
+
+
+if __name__ == '__main__':
+  unittest.main()
diff --git a/src/test/py/bazel/empty_test.py b/src/test/py/bazel/empty_test.py
new file mode 100644
index 0000000000..fe6a40a8ea
--- /dev/null
+++ b/src/test/py/bazel/empty_test.py
@@ -0,0 +1,27 @@
+# Copyright 2017 The Bazel Authors. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Empty test for platforms that don't need to run a particular test.
+
+import unittest
+
+
+class EmptyTest(unittest.TestCase):
+
+  def testNothing(self):
+    pass
+
+
+if __name__ == '__main__':
+  unittest.main()
diff --git a/src/test/py/bazel/test_base.py b/src/test/py/bazel/test_base.py
index 2a2b2e574e..7d0bba7385 100644
--- a/src/test/py/bazel/test_base.py
+++ b/src/test/py/bazel/test_base.py
@@ -117,7 +117,9 @@ class TestBase(unittest.TestCase):
     if not path:
       return
     abspath = self.Path(path)
-    if os.path.exists(abspath) and not os.path.isdir(abspath):
+    if os.path.exists(abspath):
+      if os.path.isdir(abspath):
+        return
       raise IOError('"%s" (%s) exists and is not a directory' % (path, abspath))
     os.makedirs(abspath)
 
@@ -145,11 +147,13 @@ class TestBase(unittest.TestCase):
           f.write(l)
           f.write('\n')
 
-  def RunBazel(self, args):
+  def RunBazel(self, args, env_remove=None):
     """Runs "bazel <args>", waits for it to exit.
 
     Args:
       args: [string]; flags to pass to bazel (e.g. ['--batch', 'build', '//x'])
+      env_remove: set(string); optional; environment variables to NOT pass to
+        Bazel
     Returns:
       (int, [string], [string]) tuple: exit code, stdout lines, stderr lines
     """
@@ -163,7 +167,7 @@ class TestBase(unittest.TestCase):
             stdout=stdout,
             stderr=stderr,
             cwd=self._tests_root,
-            env=self._BazelEnvMap())
+            env=self._BazelEnvMap(env_remove))
         exit_code = proc.wait()
 
     with open(self._stdout, 'r') as f:
@@ -172,7 +176,7 @@ class TestBase(unittest.TestCase):
       stderr = [l.strip() for l in f.readlines()]
     return exit_code, stdout, stderr
 
-  def _BazelEnvMap(self):
+  def _BazelEnvMap(self, env_remove=None):
     """Returns the environment variable map to run Bazel."""
     if TestBase.IsWindows():
       result = []
@@ -190,12 +194,13 @@ class TestBase(unittest.TestCase):
             names.pop()
 
         os.path.walk('c:\\program files\\java\\', _Visit, result)
+
       env = {
           'SYSTEMROOT': TestBase.GetEnv('SYSTEMROOT'),
           # TODO(laszlocsomor): Let Bazel pass BAZEL_SH and JAVA_HOME to tests
           # and use those here instead of hardcoding paths.
           'JAVA_HOME': 'c:\\program files\\java\\' + sorted(result)[-1],
-          'BAZEL_SH': 'c:\\tools\\msys64\\usr\\bin\\bash.exe'
+          'BAZEL_SH': 'c:\\tools\\msys64\\usr\\bin\\bash.exe',
       }
     else:
       env = {'HOME': os.path.join(self._temp, 'home')}
@@ -206,6 +211,9 @@ class TestBase(unittest.TestCase):
     # that by checking for TEST_TMPDIR.
     env['TEST_TMPDIR'] = TestBase.GetEnv('TEST_TMPDIR')
     env['TMP'] = self._temp
+    if env_remove:
+      for e in env_remove:
+        del env[e]
     return env
 
   @staticmethod