feat: support include flag in diff-cover tool (#355)

* feat: support include in diff-cover tool

* test(diff-cover): include flag

diff_cover/diff_cover_tool.py

@@ -33,6 +33,7 @@
 IGNORE_UNSTAGED_HELP = "Ignores unstaged changes"
 IGNORE_WHITESPACE = "When getting a diff ignore any and all whitespace"
 EXCLUDE_HELP = "Exclude files, more patterns supported"
+INCLUDE_HELP = "Files to include (glob pattern)"
 SRC_ROOTS_HELP = "List of source directories (only for jacoco coverage reports)"
 COVERAGE_FILE_HELP = "coverage report (XML or lcov.info)"
 DIFF_RANGE_NOTATION_HELP = (
@@ -131,6 +132,10 @@ def parse_coverage_args(argv):
         "--exclude", metavar="EXCLUDE", type=str, nargs="+", help=EXCLUDE_HELP
     )
 
+    parser.add_argument(
+        "--include", metavar="INCLUDE", type=str, nargs="+", help=INCLUDE_HELP
+    )
+
     parser.add_argument(
         "--src-roots",
         metavar="DIRECTORY",
@@ -191,6 +196,7 @@ def generate_coverage_report(
     ignore_unstaged=False,
     include_untracked=False,
     exclude=None,
+    include=None,
     src_roots=None,
     diff_range_notation=None,
     ignore_whitespace=False,
@@ -207,6 +213,7 @@ def generate_coverage_report(
         ignore_unstaged=ignore_unstaged,
         include_untracked=include_untracked,
         exclude=exclude,
+        include=include,
     )
 
     xml_roots = [
@@ -285,6 +292,7 @@ def main(argv=None, directory=None):
         ignore_unstaged=arg_dict["ignore_unstaged"],
         include_untracked=arg_dict["include_untracked"],
         exclude=arg_dict["exclude"],
+        include=arg_dict["include"],
         src_roots=arg_dict["src_roots"],
         diff_range_notation=arg_dict["diff_range_notation"],
         ignore_whitespace=arg_dict["ignore_whitespace"],

tests/test_diff_cover_tool.py

@@ -60,15 +60,23 @@ def test_parse_invalid_arg():
             parse_coverage_args(argv)
 
 
-def test_parse_with_exclude():
+def _test_parse_with_path_patterns(name):
     argv = ["reports/coverage.xml"]
     arg_dict = parse_coverage_args(argv)
-    assert arg_dict.get("exclude") is None
+    assert arg_dict.get(f"{name}") is None
 
-    argv = ["reports/coverage.xml", "--exclude", "noneed/*.py"]
+    argv = ["reports/coverage.xml", f"--{name}", "noneed/*"]
     arg_dict = parse_coverage_args(argv)
-    assert arg_dict.get("exclude") == ["noneed/*.py"]
+    assert arg_dict.get(f"{name}") == ["noneed/*"]
 
-    argv = ["reports/coverage.xml", "--exclude", "noneed/*.py", "other/**/*.py"]
+    argv = ["reports/coverage.xml", f"--{name}", "noneed/*", "other/**/*"]
     arg_dict = parse_coverage_args(argv)
-    assert arg_dict.get("exclude") == ["noneed/*.py", "other/**/*.py"]
+    assert arg_dict.get(f"{name}") == ["noneed/*", "other/**/*"]
+
+
+def test_parse_with_include():
+    _test_parse_with_path_patterns("include")
+
+
+def test_parse_with_exclude():
+    _test_parse_with_path_patterns("exclude")