chore: checkpoint before Python removal

vendor/regex/testdata/flags.toml

@@ -0,0 +1,68 @@
+[[test]]
+name = "1"
+regex = "(?i)abc"
+haystack = "ABC"
+matches = [[0, 3]]
+
+[[test]]
+name = "2"
+regex = "(?i)a(?-i)bc"
+haystack = "Abc"
+matches = [[0, 3]]
+
+[[test]]
+name = "3"
+regex = "(?i)a(?-i)bc"
+haystack = "ABC"
+matches = []
+
+[[test]]
+name = "4"
+regex = "(?is)a."
+haystack = "A\n"
+matches = [[0, 2]]
+
+[[test]]
+name = "5"
+regex = "(?is)a.(?-is)a."
+haystack = "A\nab"
+matches = [[0, 4]]
+
+[[test]]
+name = "6"
+regex = "(?is)a.(?-is)a."
+haystack = "A\na\n"
+matches = []
+
+[[test]]
+name = "7"
+regex = "(?is)a.(?-is:a.)?"
+haystack = "A\na\n"
+matches = [[0, 2]]
+match-limit = 1
+
+[[test]]
+name = "8"
+regex = "(?U)a+"
+haystack = "aa"
+matches = [[0, 1]]
+match-limit = 1
+
+[[test]]
+name = "9"
+regex = "(?U)a+?"
+haystack = "aa"
+matches = [[0, 2]]
+
+[[test]]
+name = "10"
+regex = "(?U)(?-U)a+"
+haystack = "aa"
+matches = [[0, 2]]
+
+[[test]]
+name = "11"
+regex = '(?m)(?:^\d+$\n?)+'
+haystack = "123\n456\n789"
+matches = [[0, 11]]
+unicode = false