Check page_len in ResourceLoaderWikiModule::isKnownEmpty() for 'user' modules

In most cases, we just check whether the pages exist before saying
the module is not empty to avoid generating cached HTML without
the appropriate <script> or <link> tags.

However, for modules in the 'user' group, normal users cannot
delete their personal JavaScript/CSS pages, causing needless
extra requests, even though we know the pages are empty.

ResourceLoader::isKnownEmpty() now checks the page_len field
for modules in the 'user' group to check that there is
some actual content.

Bug: 68488
Change-Id: I0570f62887fd4642fd60367ae0b51d7dc19488ca

1 files changed, 67 insertions, 0 deletions

diff --git a/tests/phpunit/includes/resourceloader/ResourceLoaderWikiModuleTest.php b/tests/phpunit/includes/resourceloader/ResourceLoaderWikiModuleTest.php
new file mode 100644
index 000000000000..50f88c825f3a
--- /dev/null
+++ b/tests/phpunit/includes/resourceloader/ResourceLoaderWikiModuleTest.php
@@ -0,0 +1,67 @@
+<?php
+
+class ResourceLoaderWikiModuleTest extends ResourceLoaderTestCase {
+
+	/**
+	 * @covers ResourceLoaderWikiModule::isKnownEmpty
+	 * @dataProvider provideIsKnownEmpty
+	 */
+	public function testIsKnownEmpty( $titleInfo, $group, $expected ) {
+		$module = $this->getMockBuilder( 'ResourceLoaderWikiModuleTestModule' )
+			->setMethods( array( 'getTitleInfo', 'getGroup' ) )
+			->getMock();
+		$module->expects( $this->any() )
+			->method( 'getTitleInfo' )
+			->will( $this->returnValue( $titleInfo ) );
+		$module->expects( $this->any() )
+			->method( 'getGroup' )
+			->will( $this->returnValue( $group ) );
+		$context = $this->getMockBuilder( 'ResourceLoaderContext' )
+			->disableOriginalConstructor()
+			->getMock();
+		$this->assertEquals( $expected, $module->isKnownEmpty( $context ) );
+	}
+
+	public function provideIsKnownEmpty() {
+		return array(
+			// No valid pages
+			array( array(), 'test1', true ),
+			// 'site' module with a non-empty page
+			array(
+				array(
+					'MediaWiki:Common.js' => array(
+						'timestamp' => 123456789,
+						'length' => 1234
+					)
+				), 'site', false,
+			),
+			// 'site' module with an empty page
+			array(
+				array(
+					'MediaWiki:Monobook.js' => array(
+						'timestamp' => 987654321,
+						'length' => 0,
+					),
+				), 'site', false,
+			),
+			// 'user' module with a non-empty page
+			array(
+				array(
+					'User:FooBar/common.js' => array(
+						'timestamp' => 246813579,
+						'length' => 25,
+					),
+				), 'user', false,
+			),
+			// 'user' module with an empty page
+			array(
+				array(
+					'User:FooBar/monobook.js' => array(
+						'timestamp' => 1357924680,
+						'length' => 0,
+					),
+				), 'user', true,
+			),
+		);
+	}
+}