Add the new test suite.

This test suite has been in use for a long time now, in place of the obsolete and unmanageable testparser.py and testfuncs.py. It verifies the complete optimizer output to stdout and stderr, to ensure that the output matches the expectations.

See unit_tests/README.txt for more info.

unit_tests/expr.suite/string-funcs.out

@@ -0,0 +1,195 @@
+[ "abc"
+, "abc"
+, "abc"
+, "abc"
+, "abc"
+, "abcxy"
+, "abcxy"
+, "abcxy"
+, "xabcy"
+, "xyabc"
+, "xyabc"
+, "AZAZＡＺＡＺ"
+, "azazａｚａｚ"
+, "ΤΆΧΙΣΤΗ ΑΛΏΠΗΞ ΒΑΦΉΣ ΨΗΜΈΝΗ ΓΗ, ΔΡΑΣΚΕΛΊΖΕΙ ΥΠΈΡ ΝΩΘΡΟΎ ΚΥΝΌΣ"
+, "τάχιστη αλώπηξ βαφήσ ψημένη γη, δρασκελίζει υπέρ νωθρού κυνόσ"
+, "abcd"
+, "abcd"
+, "bcd"
+, "cd"
+, "d"
+, ""
+, "bcd"
+, ""
+, ""
+, ""
+, ""
+, ""
+, ""
+, "abcd"
+, "bcd"
+, "cd"
+, ""
+, "bcd"
+, ""
+, ""
+, ""
+, ""
+, ""
+, "bcd"
+, ""
+, "bcd"
+, ""
+, ""
+, ""
+, "ab"
+, "b"
+, ""
+, "abd"
+, "ab"
+, "b"
+, ""
+, "abd"
+, "ab"
+, "ab"
+, "ab"
+, "abc"
+, "bc"
+, "c"
+, ""
+, "abc"
+, "bc"
+, "c"
+, ""
+, "abc"
+, "abc"
+, "abc"
+, ""
+, ""
+, "bcd"
+, ""
+, "bcd"
+, ""
+, ""
+, "abc"
+, "bc"
+, "abc"
+, "bc"
+, ""
+, "abc"
+, "abc"
+, "abc"
+, "abcd"
+, "abcd"
+, "bcd"
+, ""
+, "bcd"
+, "d"
+, ""
+, "abcd"
+, "abcd"
+, "abcd"
+, "abcd"
+, "bcd"
+, ""
+, "bcd"
+, "d"
+, ""
+, ""
+, ""
+, ""
+, ""
+, ""
+, "a"
+, "ab"
+, "abc"
+, "abcd"
+, "a"
+, "abcd"
+, "abcd"
+, "abcd"
+, "abcd"
+, "abcd"
+, "abcd"
+, ""
+, "a"
+, "ab"
+, "abcd"
+, "a"
+, "abcd"
+, "abcd"
+, "abcd"
+, "abcd"
+, "abcd"
+, "a"
+, "abcd"
+, "a"
+, "abcd"
+, "abcd"
+, "abcd"
+, "cd"
+, "acd"
+, "abcd"
+, "c"
+, "cd"
+, "acd"
+, "abcd"
+, "c"
+, "cd"
+, "cd"
+, "cd"
+, "d"
+, "ad"
+, "abd"
+, "abcd"
+, "d"
+, "ad"
+, "abd"
+, "abcd"
+, "d"
+, "d"
+, "d"
+, "abcd"
+, "abcd"
+, "a"
+, "abcd"
+, "a"
+, "abcd"
+, "abcd"
+, "d"
+, "ad"
+, "d"
+, "ad"
+, "abcd"
+, "d"
+, "d"
+, "d"
+, ""
+, ""
+, "a"
+, "abcd"
+, "a"
+, "abc"
+, "abcd"
+, ""
+, ""
+, ""
+, ""
+, "a"
+, "abcd"
+, "a"
+, "abc"
+, "abcd"
+, "abcd"
+, "abcd"
+, ""
+, 0
+, 10
+, -1
+, 0
+, -1
+, 0
+, -1
+, "a"
+, ""
+]