Deprecate non-variadic use of some functions

The new version of PHPCS no longer likes how we indicate the possible
variadic use of these functions. PHP 5.6 has been released for quite a
while; let’s start phasing out the non-variadic way to use these
functions. (Eventually, we can then declare the parameters with a strict
type hint, removing our own type checks e. g. in StatementList.)

Bug: T253636

Author: lucaswerkmeister

RELEASE-NOTES.md

@@ -1,5 +1,15 @@
 # Wikibase DataModel release notes
 
+## Version 9.6.0 (development)
+
+* `ReferenceList::addNewReference()`, `Statement::addNewReference()` and the `StatementList` constructor
+  supported being called with a variadic argument list, with a single array argument,
+  or (in the case of `StatementList`) with a single `Traversable` argument.
+  The latter two forms are now deprecated (though they still work);
+  please update your code:
+  for instance, change `->addNewReference( [ $x, $y ] )` to `->addNewReference( $x, $y )`,
+  and `->addNewReference( $snaks )` to `->addNewReference( ...$snaks )`.
+
 ## Version 9.5.1 (2020-06-03)
 
 * Updated release notes

src/ReferenceList.php

@@ -90,14 +90,15 @@ public function addReference( Reference $reference, $index = null ) {
 	/**
 	 * @since 1.1
 	 *
-	 * @param Snak[]|Snak $snaks
-	 * @param Snak [$snak2,...]
+	 * @param Snak ...$snaks
+	 * (passing a single Snak[] is still supported but deprecated)
 	 *
 	 * @throws InvalidArgumentException
 	 */
-	public function addNewReference( $snaks = [] /*...*/ ) {
-		if ( $snaks instanceof Snak ) {
-			$snaks = func_get_args();
+	public function addNewReference( ...$snaks ) {
+		if ( count( $snaks ) === 1 && is_array( $snaks[0] ) ) {
+			// TODO stop supporting this
+			$snaks = $snaks[0];
 		}
 
 		$this->addReference( new Reference( $snaks ) );

src/Statement/Statement.php

@@ -175,14 +175,15 @@ public function setReferences( ReferenceList $references ) {
 	/**
 	 * @since 2.0
 	 *
-	 * @param Snak[]|Snak $snaks
-	 * @param Snak [$snak2,...]
+	 * @param Snak ...$snaks
+	 * (passing a single Snak[] is still supported but deprecated)
 	 *
 	 * @throws InvalidArgumentException
 	 */
-	public function addNewReference( $snaks = [] /*...*/ ) {
-		if ( $snaks instanceof Snak ) {
-			$snaks = func_get_args();
+	public function addNewReference( ...$snaks ) {
+		if ( count( $snaks ) === 1 && is_array( $snaks[0] ) ) {
+			// TODO stop supporting this
+			$snaks = $snaks[0];
 		}
 
 		$this->references->addNewReference( $snaks );

src/Statement/StatementList.php

@@ -36,14 +36,17 @@ class StatementList implements IteratorAggregate, Comparable, Countable {
 	private $statements = [];
 
 	/**
-	 * @param Statement[]|Traversable|Statement $statements
-	 * @param Statement [$statement2,...]
+	 * @param Statement ...$statements
+	 * (passing a single Statement[] or Traversable is still supported but deprecated)
 	 *
 	 * @throws InvalidArgumentException
 	 */
-	public function __construct( $statements = [] /*...*/ ) {
-		if ( $statements instanceof Statement ) {
-			$statements = func_get_args();
+	public function __construct( ...$statements ) {
+		if ( count( $statements ) === 1 && (
+			is_array( $statements[0] ) || $statements[0] instanceof Traversable
+		) ) {
+			// TODO stop supporting this
+			$statements = $statements[0];
 		}
 
 		if ( !is_array( $statements ) && !( $statements instanceof Traversable ) ) {