issetAndEmpty.test

isset() and empty()
-----
<?php
isset($a);
isset($a, $b, $c);

empty($a);
empty(foo());
empty(array(1, 2, 3));
-----
array(
    0: Expr_Isset(
        vars: array(
            0: Expr_Variable(
                name: a
            )
        )
    )
    1: Expr_Isset(
        vars: array(
            0: Expr_Variable(
                name: a
            )
            1: Expr_Variable(
                name: b
            )
            2: Expr_Variable(
                name: c
            )
        )
    )
    2: Expr_Empty(
        expr: Expr_Variable(
            name: a
        )
    )
    3: Expr_Empty(
        expr: Expr_FuncCall(
            name: Name(
                parts: array(
                    0: foo
                )
            )
            args: array(
            )
        )
    )
    4: Expr_Empty(
        expr: Expr_Array(
            items: array(
                0: Expr_ArrayItem(
                    key: null
                    value: Scalar_LNumber(
                        value: 1
                    )
                    byRef: false
                )
                1: Expr_ArrayItem(
                    key: null
                    value: Scalar_LNumber(
                        value: 2
                    )
                    byRef: false
                )
                2: Expr_ArrayItem(
                    key: null
                    value: Scalar_LNumber(
                        value: 3
                    )
                    byRef: false
                )
            )
        )
    )
)