How to get current function name in PHP?

The function name can be easily obtained by the __FUNCTION__ or the __METHOD__
magic constant.

Method 1 (Prints function name):
__FUNCTION__ is used to resolve function name or method name (function in class).

Example:

<?php
class Test {

    public function bar() {
        var_dump(__FUNCTION__);
    }
}

function foo() {
    var_dump(__FUNCTION__);
}

// Must output string(3) 'foo'
foo();

$obj = new Test;

// Must output string(3) 'bar'
$obj->bar();

Output:

string(3) "foo"
string(3) "bar"

Method 2 (Prints function and class name):
using __METHOD__.

<?php

class Test
{
    public function foo() {
        var_dump(__METHOD__);
    }
}


function bar()
{
    var_dump(__METHOD__);
}

// Same As __FUNCTION__
bar();

$obj = new Test;

// Output the fully qualified method name "ClassName::MethodName"
$obj->foo();

Output:

string(3) "bar"
string(9) "Test::foo"

Note: this code is tested with php7.1