| package gls.ch03.s03 |
| /** |
| * GLS 3.3: |
| * Implementations first recognize Unicode escapes in their input, translating |
| * the ASCII characters backslash and 'u' followed by four hexadecimal digits |
| * to the Unicode character with the indicated hexadecimal value, and passing |
| * all other characters unchanged. |
| * |
| * @author Alan Green |
| */ |
| |
| class UnicodeEscapes2 extends GroovyTestCase { |
| |
| // GLS: If an even number of backslashes precede the 'u', it is not |
| // an escape |
| void testCountBackslash() { |
| def a = 1 |
| assert \u0061 == 1 // char 61 is 'a' |
| |
| // Not intepreted as an escape |
| // \\u0061 == 1 // @fail:parse |
| |
| assert "\u0061".length() == 1 |
| // Double backslash interpreted as a single backslash in string |
| assert "\\u0061".length() == 6 |
| assert "\\\u0061".length() == 2 |
| |
| } |
| |
| // GLS: If an eligible \ is followed by u, or more than one u, and the last u |
| // is not followed by four hexadecimal digits, then a compile-time error |
| // occurs. |
| void testFourHexDigits() { |
| // these next lines won't work. The backslash has been replace by a |
| // forwards slash so that the file parses. (Comments don't comment out |
| // unicode escapes.) |
| // assert "/u7" == "\07" //@fail:parse |
| // def /u61 = 2 //@fail:parse |
| // def /u061 = 2 //@fail:parse |
| |
| // If five digits, only the first four count |
| def \u00610 = 2 |
| assert a0 == 2 |
| } |
| void testInvalidHexDigits() { |
| // invalid hex digits |
| // assert "\ufffg" == "a" // @fail:parse |
| // assert "\uu006g" == "a" // @fail:parse |
| // assert "\uab cd" == "acd" // @fail:parse |
| } |
| } |
