changed error messages when number of arguments too few or too many

compiler/pipes/check-func-calls-and-vararg.cpp

@@ -279,12 +279,14 @@ VertexPtr CheckFuncCallsAndVarargPass::on_func_call(VertexAdaptor<op_func_call>
 
     if (f->is_extern() && func_param->type_hint && call_arg->type() == op_callback_of_builtin) {
       if (FunctionPtr f_callback = call_arg.as<op_callback_of_builtin>()->func_id) {
-        int call_n_params = func_param->type_hint->try_as<TypeHintCallable>()->arg_types.size() + call_arg.as<op_callback_of_builtin>()->args().size();
+        const auto *typed_callable = func_param->type_hint->try_as<TypeHintCallable>();
+        int call_n_params = typed_callable->arg_types.size() + call_arg.as<op_callback_of_builtin>()->args().size();
         int delta_this = f_callback->has_implicit_this_arg() ? 1 : 0;
+        auto expected_callback_signature = typed_callable->as_human_readable();
         kphp_error(call_n_params >= f_callback->get_min_argn(),
-                   fmt_format("Too few arguments in callback, expected {}, have {}", f_callback->get_min_argn() - delta_this, call_n_params - delta_this));
+                   fmt_format("Too many arguments for callback ({}), expected {}, have {}", expected_callback_signature, call_n_params - delta_this, f_callback->get_min_argn() - delta_this));
         kphp_error(f_callback->get_params().size() >= call_n_params,
-                   fmt_format("Too many arguments in callback, expected {}, have {}", f_callback->get_params().size() - delta_this, call_n_params - delta_this));
+                   fmt_format("Too few arguments for callback ({}), expected {}, have {}", expected_callback_signature, call_n_params - delta_this, f_callback->get_params().size() - delta_this));
 
         for (auto p : f_callback->get_params()) {
           kphp_error(!p.as<op_func_param>()->var()->ref_flag, "You can't pass callbacks with &references to built-in functions");

tests/phpt/ffi/typing/070_callback_params_error.php

@@ -1,5 +1,5 @@
 @kphp_should_fail k2_skip
-/Too few arguments in callback, expected 1, have 0/
+/Too many arguments for callback \(callable\(\): void\), expected 0, have 1/
 <?php
 
 function test() {

tests/phpt/ffi/typing/071_callback_params_error.php

@@ -1,5 +1,5 @@
 @kphp_should_fail k2_skip
-/Too many arguments in callback, expected 0, have 1/
+/Too few arguments for callback \(callable\(int\): void\), expected 1, have 0/
 <?php
 
 function test() {