Core: Support selectively disabling Migrate patches

This adds three new APIs:
* `jQuery.migrateDisablePatches`
* `jQuery.migrateEnablePatches`
* `jQuery.migrateIsPatchEnabled`

allowing to selectively disable/re-enable patches in runtime. Source code is
refactored to avoid manually overwriting jQuery methods in favor of using
`migratePatchAndWarnFunc` or `migratePatchFunc` which cooperate with above
methods.

The `jQuery.UNSAFE_restoreLegacyHtmlPrefilter` API, introduced in Migrate 3.2.0,
is now deprecated in favor of calling:
```js
jQuery.migrateEnablePatches( "self-closed-tags" );
```

The commit also reorganizes test code a bit, grouping modules testing patches
to jQuery modules in a separate directory and extracting tests of Migrate APIs
out of `core.js` to a separate `migrate.js` file. Helper files are now put in
`test/data/` and unit tests in `test/unit/`; jQuery patch tests are in
`test/unit/jquery/`.

Fixes gh-449
Closes gh-450

Author: mgol

Gruntfile.js

@@ -11,20 +11,21 @@ module.exports = function( grunt ) {
 		"dist/jquery-migrate.min.js",
 		"test/data/compareVersions.js",
 
-		"test/testinit.js",
-		"test/migrate.js",
-		"test/core.js",
-		"test/ajax.js",
-		"test/attributes.js",
-		"test/css.js",
-		"test/data.js",
-		"test/deferred.js",
-		"test/effects.js",
-		"test/event.js",
-		"test/manipulation.js",
-		"test/offset.js",
-		"test/serialize.js",
-		"test/traversing.js",
+		"test/data/testinit.js",
+		"test/data/test-utils.js",
+		"test/unit/migrate.js",
+		"test/unit/jquery/core.js",
+		"test/unit/jquery/ajax.js",
+		"test/unit/jquery/attributes.js",
+		"test/unit/jquery/css.js",
+		"test/unit/jquery/data.js",
+		"test/unit/jquery/deferred.js",
+		"test/unit/jquery/effects.js",
+		"test/unit/jquery/event.js",
+		"test/unit/jquery/manipulation.js",
+		"test/unit/jquery/offset.js",
+		"test/unit/jquery/serialize.js",
+		"test/unit/jquery/traversing.js",
 
 		{ pattern: "dist/jquery-migrate.js", included: false, served: true },
 		{ pattern: "test/**/*.@(js|json|css|jpg|html|xml)", included: false, served: true }

README.md

@@ -56,6 +56,14 @@ This plugin adds some properties to the `jQuery` object that can be used to prog
 
 `jQuery.migrateDeduplicateWarnings`: By default, Migrate only gives a specific warning once. If you set this property to `false` it will give a warning for every occurrence each time it happens. Note that this can generate a lot of output, for example when a warning occurs in a loop.
 
+`jQuery.migrateDisablePatches`: Disables patches by their codes. You can find a code for each patch in square brackets in [warnings.md](https://github.com/jquery/jquery-migrate/blob/main/warnings.md). A limited number of warnings doesn't have codes defined and cannot be disabled. These are mostly setup issues like using an incorrect version of jQuery or loading Migrate multiple times.
+
+`jQuery.migrateDisablePatches`: Disables patches by their codes.
+
+`jQuery.migrateIsPatchEnabled`: Returns `true` if a patch of a provided code is enabled and `false` otherwise.
+
+`jQuery.UNSAFE_restoreLegacyHtmlPrefilter`: A deprecated alias of `jQuery.migrateEnablePatches( "self-closed-tags" )`
+
 ## Reporting problems
 
 Bugs that only occur when the jQuery Migrate plugin is used should be reported in the [jQuery Migrate Issue Tracker](https://github.com/jquery/jquery-migrate/issues) and should be accompanied by an executable test case that demonstrates the bug. The easiest way to do this is via an online test tool such as [jsFiddle.net](https://jsFiddle.net/) or [jsbin.com](https://jsbin.com). Use the development version when you are reporting bugs.