Add some unit tests for WP_HTTP::parse_url() to cover the <PHP 5.4.7 compatibility alterations.

These unit tests cover the expected vehaviour of certain combinations of URL's, but makes no attempt to test invalid URL structures, as PHP's behavious for invalid URL's is undefined (Some will be treated as paths, others fail, and it varies between PHP 5.4.7+ and <5.4.7).
This change also makes WP_HTTP::parse_url() protected in order to allow unit testing.
See #28001, #29886


git-svn-id: https://develop.svn.wordpress.org/trunk@29864 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/class-http.php

@@ -682,11 +682,11 @@ class WP_Http {
 	 *
 	 * @since 4.1.0
 	 *
-	 * @access private
+	 * @access protected
 	 * @param  string $url The URL to parse
 	 * @return bool|array False on failure; Array of URL components on success; See parse_url()'s return values.
 	 */
-	private static function parse_url( $url ) {
+	protected static function parse_url( $url ) {
 		$parts = @parse_url( $url );
 		if ( ! $parts ) {
 			// < PHP 5.4.7 compat, trouble with relative paths including a scheme break in the path

tests/phpunit/tests/http/http.php

@@ -66,4 +66,49 @@ class Tests_HTTP_HTTP extends WP_UnitTestCase {
 			array( '//example.com/sub/', 'https://example.net', 'https://example.com/sub/' ),
 		);
 	}
+
+	/**
+	 * @dataProvider parse_url_testcases
+	 */
+	function test_parse_url( $url, $expected ) {
+		if ( ! is_callable( array( 'WP_HTTP_Testable', 'parse_url' ) ) ) {
+			$this->markTestSkipped( "This version of WP_HTTP doesn't support WP_HTTP::parse_url()" );
+			return;
+		}
+		$actual = WP_HTTP_Testable::parse_url( $url );
+		$this->assertEquals( $expected, $actual );
+	}
+
+	function parse_url_testcases() {
+		// 0: The URL, 1: The expected resulting structure
+		return array(
+			array( 'http://example.com/', array( 'scheme' => 'http', 'host' => 'example.com', 'path' => '/' ) ),
+
+			// < PHP 5.4.7: Schemeless URL
+			array( '//example.com/path/', array( 'host' => 'example.com', 'path' => '/path/' ) ),
+			array( '//example.com/', array( 'host' => 'example.com', 'path' => '/' ) ),
+			array( 'http://example.com//path/', array( 'scheme' => 'http', 'host' => 'example.com', 'path' => '//path/' ) ),
+
+			// < PHP 5.4.7: Scheme seperator in the URL
+			array( 'http://example.com/http://example.net/', array( 'scheme' => 'http', 'host' => 'example.com', 'path' => '/http://example.net/' ) ),
+			array( '/path/http://example.net/', array( 'path' => '/path/http://example.net/' ) ),
+			// PHP's parse_url() calls this an invalid url, we handle it as a path
+			array( '/://example.com/', array( 'path' => '/://example.com/' ) ),
+
+		);
+		/*
+		Untestable edge cases in various PHP:
+		  - ///example.com - Fails in PHP >= 5.4.7, assumed path in <5.4.7
+		  - ://example.com - assumed path in PHP >= 5.4.7, fails in <5.4.7
+		*/
+	}
 }
+
+/**
+ * A Wrapper of WP_HTTP to make parse_url() publicaly accessible for testing purposes.
+ */
+class WP_HTTP_Testable extends WP_HTTP {
+	public static function parse_url( $url ) {
+		return parent::parse_url( $url );
+	}
+}