fix regression in --email option and zero args

option —email at CLI once again has highest precedence.  added an
integration test for this instance to make sure it stays fixed.

also fixed a regression that had broken printing help by default when
given zero args.

Review: D18650

Auditors: csilvers, alpert

Author: Matthew Rothenberg

bin/ka-clone

@@ -82,7 +82,8 @@ def die_if_not_valid_git_repo():
 
 def _default_email():
     try:
-        return subprocess.check_output(["git", "config", "kaclone.email"])
+        kac_email = subprocess.check_output(["git", "config", "kaclone.email"])
+        return kac_email.rstrip()
     except subprocess.CalledProcessError:
         return os.environ['USER'] + "@" + DEFAULT_EMAIL_DOMAIN
 
@@ -209,7 +210,7 @@ def _chomp(s, sep):
 def _cli_process_current_dir(cli_args):
     die_if_not_valid_git_repo()
     if not cli_args.no_email:
-        set_email()
+        set_email(args.email)
     if not cli_args.no_lint:
         install_commit_linter()
     if not cli_args.no_msg:
@@ -232,6 +233,10 @@ if __name__ == '__main__':
             # TODO(mroth): allow --repair to take an optional target
         _cli_process_current_dir(args)
     else:
+        if not args.src:
+            parser.print_help()
+            sys.exit(0)
+
         _dst = _clone_repo(args.src, args.dst, args.quiet)
         logging.info(
             "Configuring your cloned git repository with KA defaults..."

examples/errors.t

@@ -47,3 +47,16 @@ design decision, so those config files can continue to be updated as they have
 in the past, and existing global configurations will work--hence better reverse
 compatibility. Also, the user can find them to manually modify somewhere they
 might expect if they are old-school.)
+
+
+Regression test: providing --email at command line should always have
+precedence over any default email guesses:
+
+  $ ka-clone $REPO repowithcustomemail --email=me@you.com --no-lint --no-gitconfig --no-msg
+  Cloning into 'repowithcustomemail'...
+  .* (re)
+  done.
+  Configuring your cloned git repository with KA defaults...
+  -> Set user.email to me@you.com
+  $ cd repowithcustomemail && git config --local user.email
+  me@you.com