[RFC,v2,11/12] kunit: mock: add struct param matcher

diff --git a/include/kunit/mock.h b/include/kunit/mock.h
index 9252a0abd295..df99ae5ac721 100644
--- a/include/kunit/mock.h
+++ b/include/kunit/mock.h
@@ -758,8 +758,18 @@  struct mock_param_matcher *kunit_ptr_ge(struct kunit *test, void *expected);
 struct mock_param_matcher *kunit_memeq(struct kunit *test,
 				      const void *buf,
 				      size_t size);
+
 struct mock_param_matcher *kunit_streq(struct kunit *test, const char *str);
 
+struct mock_param_matcher *kunit_str_contains(struct kunit *test,
+					      const char *needle);
+
+/* Matches var-arg arguments. */
+struct mock_param_matcher *kunit_va_format_cmp(
+		struct kunit *test,
+		struct mock_param_matcher *fmt_matcher,
+		struct mock_param_matcher *va_matcher);
+
 struct mock_action *kunit_u8_return(struct kunit *test, u8 ret);
 struct mock_action *kunit_u16_return(struct kunit *test, u16 ret);
 struct mock_action *kunit_u32_return(struct kunit *test, u32 ret);
@@ -778,4 +788,52 @@  struct mock_action *kunit_ulonglong_return(struct kunit *test,
 					  unsigned long long ret);
 struct mock_action *kunit_ptr_return(struct kunit *test, void *ret);
 
+/**
+ * struct mock_struct_matcher_entry - composed with other &struct
+ *                                    mock_struct_matcher_entry to make a
+ *                                    &struct struct_matcher
+ * @member_offset: offset of this member
+ * @matcher: matcher for this particular member
+ *
+ * This is used for struct_cmp() matchers.
+ */
+struct mock_struct_matcher_entry {
+	size_t member_offset;
+	struct mock_param_matcher *matcher;
+};
+
+static inline void init_mock_struct_matcher_entry_internal(
+		struct mock_struct_matcher_entry *entry,
+		size_t offset,
+		struct mock_param_matcher *matcher)
+{
+	entry->member_offset = offset;
+	entry->matcher = matcher;
+}
+
+/**
+ * INIT_MOCK_STRUCT_MATCHER_ENTRY()
+ * @entry: the &struct mock_struct_matcher_entry to initialize
+ * @type: the struct being matched
+ * @member: the member of the struct being matched, used to calculate the offset
+ * @matcher: matcher to match that member
+ *
+ * Initializes ``entry`` to match ``type->member`` with ``matcher``.
+ */
+#define INIT_MOCK_STRUCT_MATCHER_ENTRY(entry, type, member, matcher)	       \
+		init_mock_struct_matcher_entry_internal(entry,		       \
+							offsetof(type, member),\
+							matcher)
+
+static inline void INIT_MOCK_STRUCT_MATCHER_ENTRY_LAST(
+		struct mock_struct_matcher_entry *entry)
+{
+	entry->matcher = NULL;
+}
+
+struct mock_param_matcher *kunit_struct_cmp(
+		struct kunit *test,
+		const char *struct_name,
+		struct mock_struct_matcher_entry *entries);
+
 #endif /* _KUNIT_MOCK_H */
diff --git a/lib/kunit/common-mocks.c b/lib/kunit/common-mocks.c
index ce8929157ded..6a4cc9c60427 100644
--- a/lib/kunit/common-mocks.c
+++ b/lib/kunit/common-mocks.c
@@ -228,6 +228,123 @@  struct mock_param_matcher *kunit_streq(struct kunit *test, const char *str)
 	return &matcher->matcher;
 }
 
+struct mock_str_contains_matcher {
+	struct mock_param_matcher matcher;
+	const char *needle;
+};
+
+static bool match_str_contains(struct mock_param_matcher *pmatcher,
+			       struct kunit_stream *stream,
+			       const void *phaystack)
+{
+	struct mock_str_contains_matcher *matcher =
+		container_of(pmatcher,
+			     struct mock_str_contains_matcher,
+			     matcher);
+	const char *haystack = CONVERT_TO_ACTUAL_TYPE(const char *, phaystack);
+	bool matches = strstr(haystack, matcher->needle);
+
+	if (matches)
+		kunit_stream_add(stream,
+				 "'%s' found in '%s'",
+				 matcher->needle,
+				 haystack);
+	else
+		kunit_stream_add(stream,
+				 "'%s' not found in '%s'",
+				 matcher->needle,
+				 haystack);
+	return matches;
+}
+
+struct mock_param_matcher *kunit_str_contains(struct kunit *test,
+					      const char *str)
+{
+	struct mock_str_contains_matcher *matcher;
+
+	matcher = kunit_kzalloc(test, sizeof(*matcher), GFP_KERNEL);
+	if (!matcher)
+		return NULL;
+
+	matcher->matcher.match = match_str_contains;
+	matcher->needle = str;
+
+	return &matcher->matcher;
+}
+
+struct mock_param_matcher *kunit_va_format_cmp(
+		struct kunit *test,
+		struct mock_param_matcher *fmt_matcher,
+		struct mock_param_matcher *va_matcher)
+{
+	struct mock_struct_matcher_entry *entries;
+
+	entries = kunit_kzalloc(test, sizeof(*entries) * 3, GFP_KERNEL);
+	if (!entries)
+		return NULL;
+
+	INIT_MOCK_STRUCT_MATCHER_ENTRY(&entries[0],
+				       struct va_format,
+				       fmt,
+				       fmt_matcher);
+	INIT_MOCK_STRUCT_MATCHER_ENTRY(&entries[1],
+				       struct va_format,
+				       va,
+				       va_matcher);
+	INIT_MOCK_STRUCT_MATCHER_ENTRY_LAST(&entries[2]);
+
+	return kunit_struct_cmp(test, "va_format", entries);
+}
+
+struct mock_struct_matcher {
+	struct mock_param_matcher matcher;
+	const char *struct_name;
+	struct mock_struct_matcher_entry *entries;
+};
+
+static bool match_struct(struct mock_param_matcher *pmatcher,
+			 struct kunit_stream *stream,
+			 const void *pactual)
+{
+	struct mock_struct_matcher *matcher =
+			container_of(pmatcher,
+				     struct mock_struct_matcher,
+				     matcher);
+	struct mock_struct_matcher_entry *entry;
+	const char *actual = CONVERT_TO_ACTUAL_TYPE(const char *, pactual);
+	const char *member_ptr;
+	bool matches = true, tmp;
+
+	kunit_stream_add(stream, "struct %s {", matcher->struct_name);
+	for (entry = matcher->entries; entry->matcher; entry++) {
+		member_ptr = actual + entry->member_offset;
+		tmp = entry->matcher->match(entry->matcher, stream, member_ptr);
+		matches = matches && tmp;
+		kunit_stream_add(stream, ", ");
+	}
+	kunit_stream_add(stream, "}");
+
+	return matches;
+}
+
+struct mock_param_matcher *kunit_struct_cmp(
+		struct kunit *test,
+		const char *struct_name,
+		struct mock_struct_matcher_entry *entries)
+{
+	struct mock_struct_matcher *matcher;
+
+	matcher = kunit_kzalloc(test, sizeof(*matcher), GFP_KERNEL);
+	if (!matcher)
+		return NULL;
+
+	matcher->matcher.match = match_struct;
+	matcher->struct_name = struct_name;
+	matcher->entries = entries;
+
+	return &matcher->matcher;
+}
+
 #define DEFINE_RETURN_ACTION_STRUCT(type_name, type)			       \
 		struct mock_##type_name##_action {			       \
 			struct mock_action action;			       \
diff --git a/lib/kunit/mock-test.c b/lib/kunit/mock-test.c
index 8a0fa33d087c..df0969b43ade 100644
--- a/lib/kunit/mock-test.c
+++ b/lib/kunit/mock-test.c
@@ -243,6 +243,45 @@  static void mock_test_do_expect_default_return(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, 0, expectation->times_called);
 }
 
+/*
+ * Method called on naggy mock with no expectations will not fail, but will show
+ * a warning message
+ */
+static void mock_test_naggy_no_expectations_no_fail(struct kunit *test)
+{
+	struct mock_test_context *ctx = test->priv;
+	struct kunit *failing_test = ctx->failing_test;
+	struct mock *mock = ctx->mock;
+
+	int param0 = 5, param1 = -5;
+	static const char * const two_param_types[] = {"int", "int"};
+	const void *two_params[] = {&param0, &param1};
+
+	mock_set_default_action(mock,
+				"add",
+				real_add,
+				kunit_int_return(failing_test, -4));
+
+
+	KUNIT_EXPECT_CALL(mock_add(
+			mock,
+			kunit_any(failing_test),
+			kunit_va_format_cmp(failing_test,
+					    kunit_str_contains(failing_test,
+							       "Method was called with no expectations declared"),
+					    kunit_any(failing_test))));
+
+	mock->do_expect(mock,
+			"add",
+			real_add,
+			two_param_types,
+			two_params,
+			ARRAY_SIZE(two_params));
+	mock_validate_expectations(mock);
+
+	KUNIT_EXPECT_FALSE(test, failing_test->success);
+}
+
 static void mock_test_mock_validate_expectations(struct kunit *test)
 {
 	struct mock_test_context *ctx = test->priv;
@@ -307,6 +346,7 @@  static struct kunit_case mock_test_cases[] = {
 	KUNIT_CASE(mock_test_failed_expect_call_fails_test),
 	KUNIT_CASE(mock_test_do_expect_default_return),
 	KUNIT_CASE(mock_test_mock_validate_expectations),
+	KUNIT_CASE(mock_test_naggy_no_expectations_no_fail),
 	{}
 };