Always preserve keys and use first item in unique()

Author: aimeos

README.md

@@ -6947,7 +6947,7 @@ Two elements are considered equal if comparing their string representions return
 (string) $elem1 === (string) $elem2
 ```
 
-The keys of the elements are only preserved in the new map if the first parameter is NULL.
+The keys of the elements are preserved in the new map.
 
 **Examples:**
 
@@ -6956,13 +6956,13 @@ Map::from( [0 => 'a', 1 => 'b', 2 => 'b', 3 => 'c'] )->unique();
 // [0 => 'a', 1 => 'b', 3 => 'c']
 
 Map::from( [['p' => '1'], ['p' => 1], ['p' => 2]] )->unique( 'p' );
-// [['p' => 1], ['p' => 2]]
+// [0 => ['p' => '1'], 2 => ['p' => 2]]
 
 Map::from( [['i' => ['p' => '1']], ['i' => ['p' => 1]]] )->unique( 'i/p' );
-// [['i' => ['p' => 1]]]
+// [0 => ['i' => ['p' => '1']]]
 
 Map::from( [['i' => ['p' => '1']], ['i' => ['p' => 1]]] )->unique( fn( $item, $key ) => $item['i']['p'] );
-// [['i' => ['p' => 1]]]
+// [0 => ['i' => ['p' => '1']]]
 ```
 
 **See also:**

src/Map.php

@@ -5736,8 +5736,8 @@ public function union( iterable $elements ) : self
 	 * Results:
 	 * [0 => 'a', 1 => 'b', 3 => 'c']
 	 * [['p' => 1], ['p' => 2]]
-	 * [['i' => ['p' => 1]]]
-	 * [['i' => ['p' => 1]]]
+	 * [['i' => ['p' => '1']]]
+	 * [['i' => ['p' => '1']]]
 	 *
 	 * Two elements are considered equal if comparing their string representions returns TRUE:
 	 * (string) $elem1 === (string) $elem2
@@ -5749,25 +5749,32 @@ public function union( iterable $elements ) : self
 	 */
 	public function unique( $col = null ) : self
 	{
-		if( $col instanceof \Closure )
+		if( $col === null ) {
+			return new static( array_unique( $this->list() ) );
+		}
+
+		if( !( $col instanceof \Closure ) )
 		{
-			$unique = [];
+			$parts = explode( $this->sep, (string) $col );
 
-			foreach( $this->list() as $key => $item )
-			{
-				$value = (string) $col( $item, $key );
-				$unique[$value] = $item;
-			}
+			$col = function( $item ) use ( $parts ) {
+				return $this->val( $item, $parts );
+			};
+		}
 
-			return new static( array_values( $unique ) );
+		$list = $unique = [];
 
-		}
+		foreach( $this->list() as $key => $item )
+		{
+			$value = (string) $col( $item, $key );
 
-		if( $col !== null ) {
-			return $this->col( null, $col )->values();
+			if( !isset( $unique[$value] ) ) {
+				$unique[$value] = true;
+				$list[$key] = $item;
+			}
 		}
 
-		return new static( array_unique( $this->list() ) );
+		return new static( $list );
 	}
 
 

tests/MapTest.php

@@ -3784,7 +3784,7 @@ public function testUniqueKey()
 		$r = $m->unique( 'p' );
 
 		$this->assertInstanceOf( Map::class, $r );
-		$this->assertSame( [['p' => 1], ['p' => 2]], $r->toArray() );
+		$this->assertSame( [0 => ['p' => '1'], 2 => ['p' => 2]], $r->toArray() );
 	}
 
 
@@ -3794,7 +3794,7 @@ public function testUniquePath()
 		$r = $m->unique( 'i/p' );
 
 		$this->assertInstanceOf( Map::class, $r );
-		$this->assertSame( [['i' => ['p' => 1]]], $r->toArray() );
+		$this->assertSame( [0 => ['i' => ['p' => '1']]], $r->toArray() );
 	}
 
 
@@ -3804,7 +3804,7 @@ public function testUniqueClosure()
 		$r = $m->unique( fn( $item, $key ) => $item['i']['p'] );
 
 		$this->assertInstanceOf( Map::class, $r );
-		$this->assertSame( [['i' => ['p' => 1]]], $r->toArray() );
+		$this->assertSame( [0 => ['i' => ['p' => '1']]], $r->toArray() );
 	}