Remove support for processors

.changeset/hot-gifts-compete.md

@@ -0,0 +1,5 @@
+---
+"stylelint": major
+---
+
+Removed: support for processors

README.md

@@ -70,7 +70,6 @@ There are also rules for enforcing stylistic conventions, but we now recommend y
   - [Writing custom syntaxes](docs/developer-guide/syntaxes.md)
   - [Writing custom formatters](docs/developer-guide/formatters.md)
   - [Writing system tests](docs/developer-guide/system-tests.md)
-  - [Writing processors](docs/developer-guide/processors.md)
 - Migration guide
   - [Migrating to 14.0.0](docs/migration-guide/to-14.md)
 - Maintainer guide

docs/migration-guide/to-15.md

@@ -1,5 +1,9 @@
 # Migrating to 15.0.0
 
+## Remove support for processors
+
+We removed the support for processors. Instead, please use [custom syntaxes](../developer-guide/syntaxes.md).
+
 ## Change of `overrides.extends` behavior
 
 We changed the `overrides.extends` behavior to merge rather than replace, to make it consistent with the `overrides.plugins`.

docs/user-guide/configure.md

@@ -388,35 +388,6 @@ If the globs are absolute paths, they are used as is. If they are relative, they
 
 _Note that this is not an efficient method for ignoring lots of files._ If you want to ignore a lot of files efficiently, use [`.stylelintignore`](ignore-code.md) or adjust your files globs.
 
-## `processors`
-
-Processors are functions built by the community that hook into Stylelint's pipeline, modifying code on its way into Stylelint and modifying results on their way out.
-
-**We discourage their use in favor of using the [`customSyntax` option](#customsyntax) as processors are incompatible with the [autofix feature](usage/options.md#fix).**
-
-To use one, add a `"processors"` array to your config, containing "locaters" identifying the processors you want to use. As with `extends`, above, a "locater" can be either an npm module name, an absolute path, or a path relative to the invoking configuration file.
-
-```json
-{
-  "processors": ["stylelint-my-processor"],
-  "rules": {}
-}
-```
-
-If your processor has options, make that item an array whose first item is the "locator" and second item is the options object.
-
-```json
-{
-  "processors": [
-    "stylelint-my-processor",
-    ["some-other-processor", { "optionOne": true, "optionTwo": false }]
-  ],
-  "rules": {}
-}
-```
-
-Processors can also only be used with the CLI and the Node.js API, not with the PostCSS plugin. (The PostCSS plugin ignores them.)
-
 ## `report*`
 
 These `report*` properties provide extra validation for `stylelint-disable` comments. This can be helpful for enforcing useful and well-documented disables.