Selector: Inline Sizzle into the selector module: 3.x version (#5113)

This commit removes Sizzle from jQuery, inlining its code & removing obsolete
workarounds where applicable.

The Sizzle AUTHORS.txt file has been merged with the jQuery one - people are
sorted by their first contributions to either of the two repositories.

The main `selector` module can be disabled in favor of `selector-native`
via:

    grunt custom:-selector

For backwards compatibility, the legacy `sizzle` alias is also supported (it
will be dropped in jQuery `4.0.0`):

    grunt custom:-selector

Sizzle tests have been ported to jQuery ones. Ones that are not compatible
with the `selector-native` module are disabled if the regular selector module
is excluded.

Backwards compatibility is still kept for all `Sizzle` utils - they continue to be
available under `jQuery.find` - but the primary implementation is now attached
directly to jQuery.

Some selector utils shared by `selector` & `selector-native` have been
extracted & deduplicated. `jQuery.text` and `jQuery.isXMLDoc` have been
moved to the `core` module.

The commit reduces the gzipped jQuery size by 851 bytes compared to the
`3.x-stable` branch.

Closes gh-5113
Ref gh-4395
Ref gh-4406

1 files changed, 29 insertions, 26 deletions

diff --git a/build/tasks/build.js b/build/tasks/build.js
index 71c20a81a..01b19e4d4 100644
--- a/build/tasks/build.js
+++ b/build/tasks/build.js
@@ -72,13 +72,6 @@ module.exports = function( grunt ) {
 				)
 				.replace( rdefineEnd, "" );
 
-		// Sizzle treatment
-		} else if ( /\/sizzle$/.test( name ) ) {
-			contents = "var Sizzle =\n" + contents
-
-				// Remove EXPOSE lines from Sizzle
-				.replace( /\/\/\s*EXPOSE[\w\W]*\/\/\s*EXPOSE/, "return Sizzle;" );
-
 		} else {
 
 			contents = contents
@@ -101,7 +94,7 @@ module.exports = function( grunt ) {
 
 			// Remove empty definitions
 			contents = contents
-				.replace( /define\(\[[^\]]*\]\)[\W\n]+$/, "" );
+				.replace( /define\(\s*\[[^\]]*\]\s*\)[\W\n]+$/, "" );
 		}
 
 		// AMD Name
@@ -178,14 +171,19 @@ module.exports = function( grunt ) {
 			 * Adds the specified module to the excluded or included list, depending on the flag
 			 * @param {String} flag A module path relative to
 			 *  the src directory starting with + or - to indicate
-			 *  whether it should included or excluded
+			 *  whether it should be included or excluded
 			 */
 			excluder = function( flag ) {
 				var additional,
-					m = /^(\+|\-|)([\w\/-]+)$/.exec( flag ),
+					m = /^(\+|-|)([\w\/-]+)$/.exec( flag ),
 					exclude = m[ 1 ] === "-",
 					module = m[ 2 ];
 
+				// Recognize the legacy `sizzle` alias
+				if ( module === "sizzle" ) {
+					module = "selector";
+				}
+
 				if ( exclude ) {
 
 					// Can't exclude certain modules
@@ -200,7 +198,16 @@ module.exports = function( grunt ) {
 							// These are the removable dependencies
 							// It's fine if the directory is not there
 							try {
-								excludeList( fs.readdirSync( srcFolder + module ), module );
+
+								// `selector` is a special case as we don't just remove
+								// the module, but we replace it with `selector-native`
+								// which re-uses parts of the `src/selector` folder.
+								if ( module !== "selector" ) {
+									excludeList(
+										fs.readdirSync( `${ srcFolder }/${ module }` ),
+										module
+									);
+								}
 							} catch ( e ) {
 								grunt.verbose.writeln( e );
 							}
@@ -218,11 +225,6 @@ module.exports = function( grunt ) {
 						}
 					} else {
 						grunt.log.error( "Module \"" + module + "\" is a minimum requirement." );
-						if ( module === "selector" ) {
-							grunt.log.error(
-								"If you meant to replace Sizzle, use -sizzle instead."
-							);
-						}
 					}
 				} else {
 					grunt.log.writeln( flag );
@@ -259,17 +261,16 @@ module.exports = function( grunt ) {
 			excluder( flag );
 		}
 
-		// Handle Sizzle exclusion
-		// Replace with selector-native
-		if ( ( index = excluded.indexOf( "sizzle" ) ) > -1 ) {
-			config.rawText.selector = "define(['./selector-native']);";
-			excluded.splice( index, 1 );
+		// Handle full selector module exclusion.
+		// Replace with selector-native.
+		if ( excluded.indexOf( "selector" ) > -1 ) {
+			config.rawText.selector = "define([ \"./selector-native\" ]);";
 		}
 
 		// Replace exports/global with a noop noConflict
 		if ( ( index = excluded.indexOf( "exports/global" ) ) > -1 ) {
-			config.rawText[ "exports/global" ] = "define(['../core']," +
-				"function( jQuery ) {\njQuery.noConflict = function() {};\n});";
+			config.rawText[ "exports/global" ] = "define( [\n\t\"../core\"\n], " +
+				"function( jQuery ) {\n\tjQuery.noConflict = function() {};\n} );";
 			excluded.splice( index, 1 );
 		}
 
@@ -311,9 +312,11 @@ module.exports = function( grunt ) {
 		if ( !optIn ) {
 
 			// Overwrite the default inclusions with the explicit ones provided
-			config.rawText.jquery = "define([" +
-				( included.length ? included.join( "," ) : "" ) +
-			"]);";
+			config.rawText.jquery = "define( [\n" +
+				( included.length ?
+					included.map( module => "\t\"./" + module + "\"" ).join( ",\n" ) :
+					"" ) +
+			"\n] );";
 		}
 
 		// Trace dependencies and concatenate files