Improve speed

Author: jakewhiteley

.gitignore

@@ -1,2 +1,4 @@
 /vendor/*
 .idea/
+
+Bench.php

src/Set.php

@@ -49,6 +49,24 @@ public function add($value): Set
         return $this;
     }
 
+    /**
+     * Removes the element associated to the value.
+     *
+     * @param mixed $value The value to remove from the Set object
+     * @return boolean
+     */
+    public function delete($value): bool
+    {
+        $key = array_search($value, $this->getArrayCopy(), true);
+
+        if ($key !== false) {
+            unset($this[$key]);
+            return true;
+        }
+
+        return false;
+    }
+
     /**
      * Removes all elements from the Set object. Returns the Set object.
      *
@@ -62,21 +80,14 @@ public function clear(): Set
     }
 
     /**
-     * Removes the element associated to the value.
+     * Returns a boolean asserting whether an element is present with the given value in the Set object or not.
      *
-     * @param mixed $value The value to remove from the Set object
+     * @param mixed $value The value to check for.
      * @return boolean
      */
-    public function delete($value): bool
+    public function has($value): bool
     {
-        $key = array_search($value, $this->getArrayCopy(), true);
-
-        if ($key !== false) {
-            unset($this[$key]);
-            return true;
-        }
-
-        return false;
+        return array_search($value, $this->getArrayCopy(), true) !== false;
     }
 
     /**
@@ -86,7 +97,7 @@ public function delete($value): bool
      *
      * @param callable $callback  The callback function
      *                            The callback is called with argument 1 being the current iterated value
-     * @param mixed    $args   Additional arguments to pass to the callback function
+     * @param mixed    $args      Additional arguments to pass to the callback function
      * @return Set
      */
     public function each(callable $callback, ...$args): Set
@@ -113,17 +124,6 @@ public function entries(): ArrayIterator
         return $this->getIterator();
     }
 
-    /**
-     * Returns a boolean asserting whether an element is present with the given value in the Set object or not.
-     *
-     * @param mixed $value The value to check for.
-     * @return boolean
-     */
-    public function has($value): bool
-    {
-        return array_search($value, $this->getArrayCopy(), true) !== false;
-    }
-
     /**
      * Returns an array of the values values with the Set onject
      *
@@ -144,55 +144,41 @@ public function values(): array
      */
     public function merge(Set $set): Set
     {
-        $iterator = $set->entries();
-
-        // create a copy of $set
         $merged = new Set();
         $merged->exchangeArray($this->values());
 
-        // add values from $set if not present
-        while ($iterator->valid()) {
-            if (!$this->has($iterator->current())) {
-                $merged->add($iterator->current());
+        foreach ($set->values() as $value) {
+            if (!$this->has($value)) {
+                $merged->add($value);
             }
-            $iterator->next();
         }
 
-        $iterator->rewind();
-
         return $merged;
     }
 
     /**
-     * Returns a new Set containing all uncommon items between this and a given Set instance.
+     * Returns a new Set containing values preset in this set, but not in another given set.
      *
-     * @param Set $set
+     * @param Set $set Set to compare against
      * @return Set
-     * @todo  This is not very efficient as it iterates both Sets completely
      *
      */
     public function diff(Set $set): Set
     {
-        $entries = $this->entries();
-        $iterator = $set->entries();
-        $intersect = new Set;
-
-        // check $set values
-        while ($entries->valid()) {
-            if (!$set->has($entries->current())) {
-                $intersect->add($entries->current());
-            }
+        if ($this->size === 0) {
+            return new Set();
+        }
 
-            $entries->next();
+        if ($set->size === 0) {
+            return (new Set())->merge($this);
         }
 
-        // check $additionalSet values
-        while ($iterator->valid()) {
-            if (!$this->has($iterator->current())) {
-                $intersect->add($iterator->current());
-            }
+        $intersect = new Set;
 
-            $iterator->next();
+        foreach ($this->values() as $value) {
+            if (!$set->has($value)) {
+                $intersect->add($value);
+            }
         }
 
         return $intersect;
@@ -203,22 +189,17 @@ public function diff(Set $set): Set
      * All values should be present, but ordinality does not matter
      *
      * @param Set $set The Set to check against
-     * @return bool Whether $set  was a subset of $set
+     * @return bool Whether $set was a subset of $set
      */
     public function subset(Set $set): bool
     {
-        $iterator = $set->entries();
-
         // iterate through $set and return false is an uncommon value is present
-        while ($iterator->valid()) {
-            if (!$this->has($iterator->current())) {
+        foreach ($set->values() as $value) {
+            if (!$this->has($value)) {
                 return false;
             }
-            $iterator->next();
         }
 
-        $iterator->rewind();
-
         return true;
     }
 
@@ -230,16 +211,13 @@ public function subset(Set $set): bool
      */
     public function intersect(Set $set): Set
     {
-        $iterator = $set->entries();
-        $intersect = new Set;
+        $intersect = new Set();
 
-        while ($iterator->valid()) {
-            if ($this->has($iterator->current())) {
-                $intersect->add($iterator->current());
+        foreach ($set->values() as $value) {
+            if ($this->has($value)) {
+                $intersect->add($value);
             }
-            $iterator->next();
         }
-        $iterator->rewind();
 
         return $intersect;
     }

tests/SetTest.php

@@ -21,11 +21,10 @@ public function testAdd()
     {
         $set = new Set();
         $set->add('a');
+        $this->assertSame(['a'], $set->values());
 
-        $expected = ['a'];
-        $result = $set->values();
-
-        $this->assertSame($expected, $result);
+        $set->add('a');
+        $this->assertSame(['a'], $set->values());
     }
 
     public function testDelete()
@@ -77,19 +76,32 @@ public function testDiffOnSameValues()
     }
 
     public function testDiffOnDifferentValues()
+    {
+        $set = new Set(1, 2);
+        $set2 = new Set(3, 4);
+
+        $result = $set->diff($set2);
+
+        $this->assertSame(2, $result->size);
+        $this->assertSame([1,2], $result->values());
+    }
+
+    public function testDiffOnEmptySet()
     {
         $set = new Set();
-        $set->add(1);
-        $set->add(2);
+        $set2 = new Set(3, 4);
 
-        $set2 = new Set();
-        $set2->add(3);
-        $set2->add(4);
+        $result = $set->diff($set2);
+        $this->assertSame(0, $result->size);
+    }
 
-        $expected = 4;
-        $result = $set->diff($set2)->size;
+    public function testDiffOnEmptyTargetSet()
+    {
+        $set = new Set(1,2);
+        $set2 = new Set();
 
-        $this->assertSame($expected, $result);
+        $result = $set->diff($set2);
+        $this->assertSame(2, $result->size);
     }
 
     public function testHas()