Fix running 'import run_isolated' at python interactive prompt.

run_isolated.py

Index: run_isolated.py
diff --git a/run_isolated.py b/run_isolated.py
index 0c1b4cc0c7552350a98b9caca9000d071198b25e..9e0ad754e7a0715a6ab9cd3e6bb8932ecce65107 100755
--- a/run_isolated.py
+++ b/run_isolated.py
@@ -39,7 +39,9 @@ THIS_FILE_PATH = os.path.abspath(__file__) if __file__ else None
 BASE_DIR = os.path.dirname(THIS_FILE_PATH) if __file__ else None
 
 # Directory that contains currently running script file.
-MAIN_DIR = os.path.dirname(os.path.abspath(zip_package.get_main_script_path()))
+MAIN_DIR = (

[Vadim Sh., 2013/10/01 18:59:51]

nit: I'd change it into regular 'if' and added comment describing when
get_main_script_path is None:

if zip_package.get_main_script_path():
  ....
else:
  # This happens when running from interactive interpreter shell.
  MAIN_DIR = None

[M-A Ruel, 2013/10/01 19:06:35]

Done.

+    os.path.dirname(os.path.abspath(zip_package.get_main_script_path()))
+    if zip_package.get_main_script_path() else None)
 
 # Types of action accepted by link_file().
 HARDLINK, HARDLINK_WITH_FALLBACK, SYMLINK, COPY = range(1, 5)
@@ -514,8 +516,9 @@ def run_tha_test(isolated_hash, cache_dir, retriever, policies):
     # TODO(vadimsh): Pass it via 'env_vars' in manifest.
     # Add a rotating log file if one doesn't already exist.
     env = os.environ.copy()
-    env.setdefault('RUN_TEST_CASES_LOG_FILE',
-                  os.path.join(MAIN_DIR, RUN_TEST_CASES_LOG))
+    if MAIN_DIR:
+      env.setdefault('RUN_TEST_CASES_LOG_FILE',
+                    os.path.join(MAIN_DIR, RUN_TEST_CASES_LOG))
     try:
       with tools.Profiler('RunTest'):
         return subprocess.call(settings.command, cwd=cwd, env=env)