expect_tests: add options to enable per-module runs.

expect_tests/main.py

Index: expect_tests/main.py
diff --git a/expect_tests/main.py b/expect_tests/main.py
index 38510c9568887def042ad73e72adea960bd46c58..c139b6cbc15af6edf53a7852edc4cc8f11e16ce0 100644
--- a/expect_tests/main.py
+++ b/expect_tests/main.py
@@ -60,6 +60,10 @@ def _parse_args(args):
         help='Disable coverage report.')
 
     sp.add_argument(
+        '--coveragerc', metavar='FILE',
+        help='File to read coverage configuration. Default: .coveragerc')
+
+    sp.add_argument(
         '--test-list', '--test_list', metavar='FILE',
         help='take the list of test globs from the FILE (use "-" for stdin)'
     ).completer = lambda **_: []
@@ -70,6 +74,11 @@ def _parse_args(args):
     ).completer = lambda **_: []
 
     sp.add_argument(
+        '--html-report-subdir', '--html_report_subdir', metavar='DIR',
+        help=('additional relative path within --html-report to write html '
+              'report (default: empty)'))
+
+    sp.add_argument(
         '--leak-temp', '--leak_temp', action='store_true',
         help='leak temporary directory for debugging (default: False)'
     )
@@ -152,8 +161,13 @@ def main(cover_branches=True, args=None):
     opts = _parse_args(args)
     skip_loop = opts.handler.SKIP_RUNLOOP
 
-    cover_ctx = CoverageContext(cover_branches, opts.html_report,
-                                not skip_loop)
+    html_report = opts.html_report
+    if html_report and opts.html_report_subdir:
+      html_report = os.path.join(html_report, opts.html_report_subdir)
+
+    cover_ctx = CoverageContext(cover_branches, html_report,
+                                enabled=not skip_loop,
+                                coveragerc=opts.coveragerc)
 
     # This is a quick hack to disable rude modules from implicitly configuring
     # basic logging at import-time.