bug #3186 Fix twig compare (dpinheiro)

This PR was squashed before being merged into the 3.x branch (closes #3186).

Discussion
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Fix twig compare

On twig 2.x the comparison between two variables was being done using the php operators (<, >, <=..), although on 3.x the function `twig_compare` was introduced and it had some issues

As an example
`'200' > 399` was returning `false` on twig 2.x, but on 3.x it was returning `true`.

Digging into the code I found out the comparison binaries (`GreaterBinary`, `LessBinary`, etc) were doing the wrong comparison, and the function `twig_compare` was also returning an wrong value if both variables had the same type

Now it's following the convention `-1` if first var is less, 0 if they are equal, or 1 if first var is greater

This is my first PR, so please comment if anything is wrong

Commits
-------

0d81c6e Fix twig compare

src/Extension/CoreExtension.php

@@ -989,7 +989,7 @@ function twig_compare($a, $b)
     }
 
     // fallback to <=>
-    return $b <=> $a;
+    return $a <=> $b;
 }
 
 /**

src/Node/Expression/Binary/GreaterBinary.php

@@ -24,7 +24,7 @@ public function compile(Compiler $compiler): void
         }
 
         $compiler
-            ->raw('-1 === twig_compare(')
+            ->raw('1 === twig_compare(')
             ->subcompile($this->getNode('left'))
             ->raw(', ')
             ->subcompile($this->getNode('right'))

src/Node/Expression/Binary/GreaterEqualBinary.php

@@ -24,7 +24,7 @@ public function compile(Compiler $compiler): void
         }
 
         $compiler
-            ->raw('0 >= twig_compare(')
+            ->raw('0 <= twig_compare(')
             ->subcompile($this->getNode('left'))
             ->raw(', ')
             ->subcompile($this->getNode('right'))

src/Node/Expression/Binary/LessBinary.php

@@ -24,7 +24,7 @@ public function compile(Compiler $compiler): void
         }
 
         $compiler
-            ->raw('1 === twig_compare(')
+            ->raw('-1 === twig_compare(')
             ->subcompile($this->getNode('left'))
             ->raw(', ')
             ->subcompile($this->getNode('right'))

src/Node/Expression/Binary/LessEqualBinary.php

@@ -24,7 +24,7 @@ public function compile(Compiler $compiler): void
         }
 
         $compiler
-            ->raw('0 <= twig_compare(')
+            ->raw('0 >= twig_compare(')
             ->subcompile($this->getNode('left'))
             ->raw(', ')
             ->subcompile($this->getNode('right'))

tests/Extension/CoreTest.php

@@ -285,10 +285,10 @@ public function provideCompareCases()
 
             [0, '0', '0'],
             [0, '0', '0.0'],
-            [1, '0', 'foo'],
-            [-1, '0', ''],
+            [-1, '0', 'foo'],
+            [1, '0', ''],
             [0, '42', '   42'],
-            [1, '42', '42foo'],
+            [-1, '42', '42foo'],
 
             [0, 42, '000042'],
             [0, 42, '42.0'],
@@ -310,6 +310,10 @@ public function provideCompareCases()
             [0, -INF, '-INF'],
             [0, INF, '1e1000'],
             [0, -INF, '-1e1000'],
+
+            [-1, 10, 20],
+            [-1, '10', 20],
+            [-1, 10, '20'],
         ];
     }
 }