An unpacked call carries a single Node\Arg regardless of its runtime
arity, so the arity check alone still accepted intval(...$args) as a
single-argument Native conversion and lowered the array itself:
intval(...['ff', 16]) // php::toInt(withBase) -> int(1)
strval(...['42']) // php::toString(single) -> "Array" + warning
A named argument has the same shape and need not be the value being
converted: intval(bogus: 1) must raise "Unknown named parameter", not
fold to a cast of 1.
Reject both in dispatchConversion() so the runtime determines the
expanded arity and the parameter names, matching what
dispatchFuncCall() already does for every other builtin.
The four scalar conversions are lowered to a single-argument Native cast
by dispatchConversion, which reads args[0] and ignores the rest. intval()
takes a $base as its second argument, so it was silently discarded:
intval("ff", 16); // php::toInt("ff") -> 0, PHP gives 255
intval("0x1A", 16); // php::toInt("0x1A") -> 0, PHP gives 26
intval("101", 2); // php::toInt("101") -> 101, PHP gives 5
Nothing reports the loss: the program compiles clean and the number is
simply wrong, which is easy to miss in the code that most often uses a
base - parsing hex colors, permission masks and binary flags.
A conversion call with any arity other than one now falls through to the
dynamic path, where both arguments are passed to the runtime function.
Single-argument intval(), strval(), floatval() and boolval() keep their
Native cast, so the common case is unchanged.
type_conv.phpt gains the base cases, with a literal and a variable base;
none of them were covered anywhere in the test suite. ConversionArityTest
pins the lowering decision in the generated C++.
Giandonn