feat(lexer): header, line breaks, paragraph breaks

test/lexer/lexer.c

@@ -0,0 +1,27 @@
+#include "test.h"
+
+#include "mrk/lexer.h"
+
+#define LEXER_INIT() \
+  mrk_lexer *lxr; \
+  TEST_CHECK(mrk_lexer_init(&lxr) == mrk_err_ok)
+
+void test_lexer_header() {
+  LEXER_INIT();
+
+  const char *buf = "#### hallo";
+  mrk_lexer_open(lxr, buf, 0);
+
+  mrk_token t;
+  TEST_CHECK(mrk_lexer_next(&t, lxr) == mrk_lexer_err_ok);
+  TEST_CHECK(t.type == mrk_token_type_header);
+  TEST_CHECK_(t.start == 0, "t.start == %lu", t.start);
+  TEST_CHECK(t.end == 4);
+
+  mrk_lexer_free(lxr);
+}
+
+TEST_LIST = {
+  { "lexer header", test_lexer_header },
+  { NULL, NULL }
+};