[8.x] Added sole() and soleWhere() methods for Collections

src/Illuminate/Collections/Collection.php

@@ -4,6 +4,8 @@
 
 use ArrayAccess;
 use ArrayIterator;
+use Illuminate\Collections\ItemNotFoundException;
+use Illuminate\Collections\MultipleItemsFoundException;
 use Illuminate\Support\Traits\EnumeratesValues;
 use Illuminate\Support\Traits\Macroable;
 use stdClass;
@@ -1050,6 +1052,37 @@ public function splitIn($numberOfGroups)
         return $this->chunk(ceil($this->count() / $numberOfGroups));
     }
 
+    /**
+     * Get the first item in the collection, but only if exactly
+     * item exists. Otherwise, throw an exception.
+     *
+     * @param  mixed  $key
+     * @param  mixed  $operator
+     * @param  mixed  $value
+     * @return mixed
+     *
+     * @throws \Illuminate\Collections\ItemNotFoundException
+     * @throws \Illuminate\Collections\MultipleItemsFoundException
+     */
+    public function sole($key = null, $operator = null, $value = null)
+    {
+        if (func_num_args() <= 1) {
+            $items = $this->when($key)->filter($key);
+
+            if ($items->isEmpty()) {
+                throw new ItemNotFoundException;
+            }
+
+            if ($items->count() > 1) {
+                throw new MultipleItemsFoundException;
+            }
+
+            return $items->first();
+        }
+
+        return $this->sole($this->operatorForWhere(...func_get_args()));
+    }
+
     /**
      * Chunk the collection into chunks of the given size.
      *

src/Illuminate/Collections/ItemNotFoundException.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace Illuminate\Collections;
+
+use RuntimeException;
+
+class ItemNotFoundException extends RuntimeException
+{
+}

src/Illuminate/Collections/LazyCollection.php

@@ -1010,6 +1010,32 @@ public function split($numberOfGroups)
         return $this->passthru('split', func_get_args());
     }
 
+    /**
+     * Get the first item in the collection, but only if exactly
+     * item exists. Otherwise, throw an exception.
+     *
+     * @param  mixed  $key
+     * @param  mixed  $operator
+     * @param  mixed  $value
+     * @return mixed
+     *
+     * @throws \Illuminate\Collections\ItemNotFoundException
+     * @throws \Illuminate\Collections\MultipleItemsFoundException
+     */
+    public function sole($key = null, $operator = null, $value = null)
+    {
+        if (func_num_args() <= 1) {
+            return $this
+                ->when($key)
+                ->filter($key)
+                ->take(2)
+                ->collect()
+                ->sole();
+        }
+
+        return $this->sole($this->operatorForWhere(...func_get_args()));
+    }
+
     /**
      * Chunk the collection into chunks of the given size.
      *

src/Illuminate/Collections/MultipleItemsFoundException.php

@@ -0,0 +1,9 @@
+<?php
+
+namespace Illuminate\Collections;
+
+use RuntimeException;
+
+class MultipleItemsFoundException extends RuntimeException
+{
+}

tests/Support/SupportCollectionTest.php

@@ -7,6 +7,8 @@
 use ArrayObject;
 use CachingIterator;
 use Exception;
+use Illuminate\Collections\ItemNotFoundException;
+use Illuminate\Collections\MultipleItemsFoundException;
 use Illuminate\Contracts\Support\Arrayable;
 use Illuminate\Contracts\Support\Jsonable;
 use Illuminate\Support\Collection;
@@ -66,6 +68,92 @@ public function testFirstWithDefaultAndWithoutCallback($collection)
         $this->assertSame('default', $result);
     }
 
+    /**
+     * @dataProvider collectionClassProvider
+     */
+    public function testSoleReturnsFirstItemInCollectionIfOnlyOneExists($collection)
+    {
+        $collection = new $collection([
+            ['name' => 'foo'],
+            ['name' => 'bar'],
+        ]);
+
+        $this->assertSame(['name' => 'foo'], $collection->where('name', 'foo')->sole());
+        $this->assertSame(['name' => 'foo'], $collection->sole('name', '=', 'foo'));
+        $this->assertSame(['name' => 'foo'], $collection->sole('name', 'foo'));
+    }
+
+    /**
+     * @dataProvider collectionClassProvider
+     */
+    public function testSoleThrowsExceptionIfNoItemsExists($collection)
+    {
+        $this->expectException(ItemNotFoundException::class);
+
+        $collection = new $collection([
+            ['name' => 'foo'],
+            ['name' => 'bar'],
+        ]);
+
+        $collection->where('name', 'INVALID')->sole();
+    }
+
+    /**
+     * @dataProvider collectionClassProvider
+     */
+    public function testSoleThrowsExceptionIfMoreThanOneItemExists($collection)
+    {
+        $this->expectException(MultipleItemsFoundException::class);
+
+        $collection = new $collection([
+            ['name' => 'foo'],
+            ['name' => 'foo'],
+            ['name' => 'bar'],
+        ]);
+
+        $collection->where('name', 'foo')->sole();
+    }
+
+    /**
+     * @dataProvider collectionClassProvider
+     */
+    public function testSoleReturnsFirstItemInCollectionIfOnlyOneExistsWithCallback($collection)
+    {
+        $data = new $collection(['foo', 'bar', 'baz']);
+        $result = $data->sole(function ($value) {
+            return $value === 'bar';
+        });
+        $this->assertSame('bar', $result);
+    }
+
+    /**
+     * @dataProvider collectionClassProvider
+     */
+    public function testSoleThrowsExceptionIfNoItemsExistsWithCallback($collection)
+    {
+        $this->expectException(ItemNotFoundException::class);
+
+        $data = new $collection(['foo', 'bar', 'baz']);
+
+        $data->sole(function ($value) {
+            return $value === 'invalid';
+        });
+    }
+
+    /**
+     * @dataProvider collectionClassProvider
+     */
+    public function testSoleThrowsExceptionIfMoreThanOneItemExistsWithCallback($collection)
+    {
+        $this->expectException(MultipleItemsFoundException::class);
+
+        $data = new $collection(['foo', 'bar', 'bar']);
+
+        $data->sole(function ($value) {
+            return $value === 'bar';
+        });
+    }
+
     /**
      * @dataProvider collectionClassProvider
      */

tests/Support/SupportLazyCollectionIsLazyTest.php

@@ -2,6 +2,7 @@
 
 namespace Illuminate\Tests\Support;
 
+use Illuminate\Collections\MultipleItemsFoundException;
 use Illuminate\Support\LazyCollection;
 use PHPUnit\Framework\TestCase;
 use stdClass;
@@ -977,6 +978,33 @@ public function testSomeIsLazy()
         });
     }
 
+    public function testSoleIsLazy()
+    {
+        $this->assertEnumerates(2, function ($collection) {
+            try {
+                $collection->sole();
+            } catch (MultipleItemsFoundException $e) {
+                //
+            }
+        });
+
+        $this->assertEnumeratesOnce(function ($collection) {
+            $collection->sole(function ($item) {
+                return $item === 1;
+            });
+        });
+
+        $this->assertEnumerates(4, function ($collection) {
+            try {
+                $collection->sole(function ($item) {
+                    return $item % 2 === 0;
+                });
+            } catch (MultipleItemsFoundException $e) {
+                //
+            }
+        });
+    }
+
     public function testSortIsLazy()
     {
         $this->assertDoesNotEnumerate(function ($collection) {