Unit Tests

PHPUnit 3.7.19 by Sebastian Bergmann.
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Time: 1 second, Memory: 4.50Mb

OK (12 tests, 35 assertions)

Lexer
[x] True
[x] Empty expression is false
[x] Parse error throws exception
[x] 1 plus 1
[x] Mul
[x] Div
[x] Arithmetic priority
[x] Parentheses
[x] Logical and
[x] Comparator equals
[x] Chaining comparisons
[x] Priority of arithmetic over comparison