[PATCH v5 04/10] kunit: string-stream: Add cases for string_stream newline appending

[Richard Fitzgerald <rf@opensource.cirrus.com>]

Add test cases for testing the string_stream feature that appends a
newline to strings that do not already end with a newline.

string_stream_no_auto_newline_test() tests with this feature disabled.
Newlines should not be added or dropped.

string_stream_auto_newline_test() tests with this feature enabled.
Newlines should be added to lines that do not end with a newline.

string_stream_append_auto_newline_test() tests appending the
content of one stream to another stream when the target stream
has newline appending enabled.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
Changes since V4:
- string_stream_append_auto_newline_test() doesn't clear the destination
  stream_1 between the newline and no-newline case. This is just a
  simplification of the code.
  
- string_stream_no_auto_newline_test() uses the same set of test strings
  as string_stream_auto_newline_test().
---
 lib/kunit/string-stream-test.c | 93 ++++++++++++++++++++++++++++++++++
 1 file changed, 93 insertions(+)

diff --git a/lib/kunit/string-stream-test.c b/lib/kunit/string-stream-test.c
index 2b761ba01835..2a9936db1b9f 100644
--- a/lib/kunit/string-stream-test.c
+++ b/lib/kunit/string-stream-test.c
@@ -32,6 +32,7 @@ static void string_stream_init_test(struct kunit *test)
 	KUNIT_EXPECT_TRUE(test, list_empty(&stream->fragments));
 	KUNIT_EXPECT_PTR_EQ(test, stream->test, test);
 	KUNIT_EXPECT_EQ(test, stream->gfp, GFP_KERNEL);
+	KUNIT_EXPECT_FALSE(test, stream->append_newlines);
 
 	KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream));
 }
@@ -214,6 +215,45 @@ static void string_stream_append_test(struct kunit *test)
 	KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1), stream_2_content);
 }
 
+/* Appending the content of one string stream to one with auto-newlining. */
+static void string_stream_append_auto_newline_test(struct kunit *test)
+{
+	struct string_stream *stream_1, *stream_2;
+
+	/* Stream 1 has newline appending enabled */
+	stream_1 = alloc_string_stream(test, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_1);
+	string_stream_set_append_newlines(stream_1, true);
+	KUNIT_EXPECT_TRUE(test, stream_1->append_newlines);
+
+	/* Stream 2 does not append newlines */
+	stream_2 = alloc_string_stream(test, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_2);
+
+	/* Appending a stream with a newline should not add another newline */
+	string_stream_add(stream_1, "Original string\n");
+	string_stream_add(stream_2, "Appended content\n");
+	string_stream_add(stream_2, "More stuff\n");
+	string_stream_append(stream_1, stream_2);
+	KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1),
+			   "Original string\nAppended content\nMore stuff\n");
+
+	string_stream_destroy(stream_2);
+	stream_2 = alloc_string_stream(test, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream_2);
+
+	/*
+	 * Appending a stream without newline should add a final newline.
+	 * The appended string_stream is treated as a single string so newlines
+	 * should not be inserted between fragments.
+	 */
+	string_stream_add(stream_2, "Another");
+	string_stream_add(stream_2, "And again");
+	string_stream_append(stream_1, stream_2);
+	KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream_1),
+			   "Original string\nAppended content\nMore stuff\nAnotherAnd again\n");
+}
+
 /* Adding an empty string should not create a fragment. */
 static void string_stream_append_empty_string_test(struct kunit *test)
 {
@@ -237,12 +277,65 @@ static void string_stream_append_empty_string_test(struct kunit *test)
 	KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream), "Add this line");
 }
 
+/* Adding strings without automatic newline appending */
+static void string_stream_no_auto_newline_test(struct kunit *test)
+{
+	struct string_stream *stream;
+
+	stream = alloc_string_stream(test, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream);
+
+	/*
+	 * Add some strings with and without newlines. All formatted newlines
+	 * should be preserved. It should not add any extra newlines.
+	 */
+	string_stream_add(stream, "One");
+	string_stream_add(stream, "Two\n");
+	string_stream_add(stream, "%s\n", "Three");
+	string_stream_add(stream, "%s", "Four\n");
+	string_stream_add(stream, "Five\n%s", "Six");
+	string_stream_add(stream, "Seven\n\n");
+	string_stream_add(stream, "Eight");
+	KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream),
+			   "OneTwo\nThree\nFour\nFive\nSixSeven\n\nEight");
+}
+
+/* Adding strings with automatic newline appending */
+static void string_stream_auto_newline_test(struct kunit *test)
+{
+	struct string_stream *stream;
+
+	stream = alloc_string_stream(test, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, stream);
+
+	string_stream_set_append_newlines(stream, true);
+	KUNIT_EXPECT_TRUE(test, stream->append_newlines);
+
+	/*
+	 * Add some strings with and without newlines. Newlines should
+	 * be appended to lines that do not end with \n, but newlines
+	 * resulting from the formatting should not be changed.
+	 */
+	string_stream_add(stream, "One");
+	string_stream_add(stream, "Two\n");
+	string_stream_add(stream, "%s\n", "Three");
+	string_stream_add(stream, "%s", "Four\n");
+	string_stream_add(stream, "Five\n%s", "Six");
+	string_stream_add(stream, "Seven\n\n");
+	string_stream_add(stream, "Eight");
+	KUNIT_EXPECT_STREQ(test, get_concatenated_string(test, stream),
+			   "One\nTwo\nThree\nFour\nFive\nSix\nSeven\n\nEight\n");
+}
+
 static struct kunit_case string_stream_test_cases[] = {
 	KUNIT_CASE(string_stream_init_test),
 	KUNIT_CASE(string_stream_line_add_test),
 	KUNIT_CASE(string_stream_variable_length_line_test),
 	KUNIT_CASE(string_stream_append_test),
+	KUNIT_CASE(string_stream_append_auto_newline_test),
 	KUNIT_CASE(string_stream_append_empty_string_test),
+	KUNIT_CASE(string_stream_no_auto_newline_test),
+	KUNIT_CASE(string_stream_auto_newline_test),
 	{}
 };
 
-- 
2.30.2