A Static Analyzer for PHP

dev-master 2015-10-23 17:55 UTC

README

Build Status

A static analysis engine...

Usage:

bin/tuli analyze file1 file2 path

Installation

Install it as a composer dependency!!!

$ composer require ircmaxell/tuli dev-master

Then simply execute vendor/bin/tuli as normal

Or check it out into its own project. Then composer install the dependencies:

$ composer install

Then simply bin/tuli to execute.

Example:

code.php:

<?php

$a = 1.0;
$b = 2;

$c = foo($a, $b);

$d = foo($b, $c);

function foo(int $a, int $b): int {
    if ($a > $b) {
        return $a + $b + 0.5;
    }
}

Then, in shell:

$ bin/tuli analyze code.php
Analyzing code.php
Determining Variable Types
Round 1 (15 unresolved variables out of 20)
.
Detecting Type Conversion Issues
Type mismatch on foo() argument 0, found float expecting int code.php:6
Type mismatch on foo() return value, found float expecting int code.php:12
Default return found for non-null type int code.php:10
Done

The three errors it found are:

  • Type mismatch on foo() argument 0, found float expecting int code.php:6

    Meaning that at code.php on line 6, you're passing a float to the first argument when it declared an integer

  • Type mismatch on foo() return value, found float expecting int code.php:12

    The value that's being returned on line 12 is a float, but it was declared as an integer in the function signature.

  • Default return found for non-null type int code.php:10

    There's a default return statement (not supplied) for a typed function

That's it!

Currently Supported Rules:

  • Function Argument Types

    It will check all typed function arguments and determine if all calls to that function match the type.

  • Function Return Types

    If the function's return value is typed, it will determine if the function actually returns that type.

  • Method Argument Types

    It will check all calls to a method for every valid typehint permutation to determine if there's a possible mismatch.

Todo:

  • A lot

Another example:

<?php

class A {
    public function foo(int $a) : int {
        return $a;
    }
}

class B extends A {
    public function foo(float $a) : float {
        return $a;
    }
}

class C extends B {
    public function foo(int $a) : int {
        return $a;
    }
}

function foo(A $a) : int {
    return $a->foo(1.0);
}

Running:

$ bin/tuli analyze code.php
Analyzing code.php

Determining Variable Types
Round 1 (5 unresolved variables out of 7)

Round 2 (3 unresolved variables out of 7)

Detecting Type Conversion Issues
Detecting Function Argument Errors
Detecting Function Return Errors
Type mismatch on foo() return value, found float expecting int code.php:22
Detecting Method Argument Errors
Type mismatch on A->foo() argument 0, found float expecting int code.php:22
Type mismatch on C->foo() argument 0, found float expecting int code.php:22
Done

Again, it found 3 errors:

  • Type mismatch on foo() return value, found float expecting int code.php:22

    It looked at all possible A::foo() method definitions (A::foo, B::foo, C::foo), and it detmermined that the general return type is float (since type widening allows int to be passed to float, but not the other way around). Therefore, returning ->foo() directly can result in a type error.

  • Type mismatch on A->foo() argument 0, found float expecting int code.php:22

  • Type mismatch on C->foo() argument 0, found float expecting int code.php:22

    We know that if you use type A or C, you're trying to pass a float to something that declares an integer.