test: Add helper to skip to partial console line

Sometimes we need to skip to a line but it includes addresses or other
information which can vary depending on the runtime conditions.

Add a new ut_assert_skip_to_linen() which is similar to the existing
ut_assert_skip_to_line() function but only checks that the console line
matches up to the length of the provided string.

Signed-off-by: Simon Glass <sjg@chromium.org>

include/test/ut.h

@@ -97,6 +97,23 @@ int ut_check_skipline(struct unit_test_state *uts);
  */
 int ut_check_skip_to_line(struct unit_test_state *uts, const char *fmt, ...);
 
+/**
+ * ut_check_skip_to_linen() - skip output until a partial line is found
+ *
+ * This creates a string and then checks it against the following lines of
+ * console output obtained with console_record_readline() until it is found.
+ * Only the characters up to the length of the string are checked, so the line
+ * may extend further
+ *
+ * After the function returns, uts->expect_str holds the expected string and
+ * uts->actual_str holds the actual string read from the console.
+ *
+ * @uts: Test state
+ * @fmt: printf() format string to look for, followed by args
+ * Return: 0 if OK, -ENOENT if not found, other value on error
+ */
+int ut_check_skip_to_linen(struct unit_test_state *uts, const char *fmt, ...);
+
 /**
  * ut_check_console_end() - Check there is no more console output
  *
@@ -359,6 +376,19 @@ int ut_check_console_dump(struct unit_test_state *uts, int total_bytes);
 	__ret;								\
 })
 
+/* Assert that a following console output line matches */
+#define ut_assert_skip_to_linen(fmt, args...) ({				\
+	int __ret = 0;							\
+									\
+	if (ut_check_skip_to_linen(uts, fmt, ##args)) {			\
+		ut_failf(uts, __FILE__, __LINE__, __func__,		\
+			 "console", "\nExpected '%s',\n     got to '%s'", \
+			 uts->expect_str, uts->actual_str);		\
+		return CMD_RET_FAILURE;					\
+	}								\
+	__ret;								\
+})
+
 /* Assert that there is no more console output */
 #define ut_assert_console_end() ({					\
 	int __ret = 0;							\