From 26f6f758a94d9291e3f9c7afc72f4a9b1d287e1e Mon Sep 17 00:00:00 2001
From: Aaron Jorbin <aaron@jorb.in>
Date: Sun, 31 Mar 2019 16:33:58 -0400
Subject: [PATCH] test fix for 46660

---
 src/wp-includes/meta.php     |  6 +++++-
 tests/phpunit/tests/meta.php | 14 ++++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/wp-includes/meta.php b/src/wp-includes/meta.php
index 2332d9b5af050..4c4cad1f9d0e5 100644
--- a/src/wp-includes/meta.php
+++ b/src/wp-includes/meta.php
@@ -207,10 +207,14 @@ function update_metadata( $meta_type, $object_id, $meta_key, $meta_value, $prev_
 	// Compare existing value to new value if no prev value given and the key exists only once.
 	if ( empty( $prev_value ) ) {
 		$old_value = get_metadata( $meta_type, $object_id, $meta_key );
-		if ( count( $old_value ) == 1 ) {
+		if ( is_array( $old_value ) && count( $old_value ) == 1 ) {
 			if ( $old_value[0] === $meta_value ) {
 				return false;
 			}
+		} else if ( ! is_array( $old_value ) ){
+			if ( $old_value === $meta_value ) {
+				return false;
+			}
 		}
 	}
 
diff --git a/tests/phpunit/tests/meta.php b/tests/phpunit/tests/meta.php
index b20f2be90d761..d7eefaa269034 100644
--- a/tests/phpunit/tests/meta.php
+++ b/tests/phpunit/tests/meta.php
@@ -416,6 +416,20 @@ public function test_get_metadata_with_empty_key_nested_array_value() {
 		$this->assertSame( array( $value ), $found['foo'] );
 	}
 
+	/**
+	 * @ticket 46660
+	 */
+	public function test_update_metadata_for_nonexistant_meta() {
+		$data  = array(
+			array( 1, 2 ),
+			array( 3, 4 ),
+		);
+		update_metadata( 'user', $this->author->ID, 'non_existant_foo', $data );
+
+		$found = get_metadata( 'user', $this->author->ID, 'non_existant_foo' );
+		$this->assertSame( $found, $data );
+	}
+
 	/** Helpers */
 
 	public function updated_meta( $meta_id ) {