Fix binary search tool install unit tests

Change from using module wide variable common.installed to using a file
called "./installed". Previously common.installed wouldn't actually be
set properly because there would be two separate instances of Python
running.

TEST=More robust install unit test made

Change-Id: Iee87a52e0f54fc63837b25918764e804747525db
Reviewed-on: https://chrome-internal-review.googlesource.com/264745
Commit-Ready: Cassidy Burden <cburden@google.com>
Tested-by: Cassidy Burden <cburden@google.com>
Reviewed-by: Caroline Tice <cmtice@google.com>

3 files changed, 17 insertions, 7 deletions

diff --git a/binary_search_tool/test/binary_search_tool_tester.py b/binary_search_tool/test/binary_search_tool_tester.py
index 73ea4d13..451543d1 100755
--- a/binary_search_tool/test/binary_search_tool_tester.py
+++ b/binary_search_tool/test/binary_search_tool_tester.py
@@ -30,6 +30,9 @@ class BisectingUtilsTest(unittest.TestCase):
       bad_obj_num = 1
     gen_obj.Main(['--obj_num', str(obj_num), '--bad_obj_num', str(bad_obj_num)])
 
+    with open('./installed', 'w'):
+      pass
+
     try:
       os.remove(binary_search_state.STATE_FILE)
     except OSError:
@@ -42,6 +45,7 @@ class BisectingUtilsTest(unittest.TestCase):
     print('Deleted "{0}" and "{1}"'.format(common.OBJECTS_FILE,
                                            common.WORKING_SET_FILE))
     try:
+      os.remove('./installed')
       os.remove(os.readlink(binary_search_state.STATE_FILE))
       os.remove(binary_search_state.STATE_FILE)
     except OSError:
@@ -57,9 +61,13 @@ class BisectingUtilsTest(unittest.TestCase):
   def test_install_script(self):
     args = ['--get_initial_items', './gen_init_list.py', '--switch_to_good',
             './switch_to_good.py', '--switch_to_bad', './switch_to_bad.py',
-            '--test_script', './is_good.py', '--prune', '--file_args',
-            '--install_script', './install.py']
-    common.installed = False
+            '--test_script', './is_good.py', '--prune', '--file_args']
+
+    os.remove('./installed')
+    with self.assertRaises(AssertionError):
+      binary_search_state.Main(args)
+
+    args += ['--install_script', './install.py']
     binary_search_state.Main(args)
     self.check_output()
 
diff --git a/binary_search_tool/test/install.py b/binary_search_tool/test/install.py
index 21cf97a1..5f721b92 100755
--- a/binary_search_tool/test/install.py
+++ b/binary_search_tool/test/install.py
@@ -5,11 +5,12 @@ from __future__ import print_function
 
 import sys
 
-import common
-
 
 def Main():
-  common.installed = True
+  # create ./installed
+  with open('./installed', 'w'):
+    pass
+
   return 0
 
 
diff --git a/binary_search_tool/test/is_good.py b/binary_search_tool/test/is_good.py
index e2ab4642..f7cc8af7 100755
--- a/binary_search_tool/test/is_good.py
+++ b/binary_search_tool/test/is_good.py
@@ -3,13 +3,14 @@
 
 from __future__ import print_function
 
+import os
 import sys
 
 import common
 
 
 def Main():
-  if not common.installed:
+  if not os.path.exists('./installed'):
     return 1
   working_set = common.ReadWorkingSet()
   for w in working_set: