Bug 1132409 - [mozlog] Create directories for log specified on the command line if not present. r=jgraham

--HG--
extra : rebase_source : f895f820c97796573a665ecc28358931700b0c43

testing/mozbase/mozlog/mozlog/structured/commandline.py

@@ -3,6 +3,7 @@
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 import sys
+import os
 import optparse
 
 from collections import defaultdict
@@ -59,8 +60,11 @@ fmt_options = {
 def log_file(name):
     if name == "-":
         return sys.stdout
-    else:
-        return open(name, "w")
+    # ensure we have a correct dirpath by using realpath
+    dirpath = os.path.dirname(os.path.realpath(name))
+    if not os.path.exists(dirpath):
+        os.makedirs(dirpath)
+    return open(name, "w")
 
 
 def add_logging_group(parser, include_formatters=None):