Fix to improve plugin, plugin tuples with boolean options

Closes GH-148.

Reviewed-by: Titus Wormer <tituswormer@gmail.com>

types/index.d.ts

@@ -36,7 +36,7 @@ export interface Processor<P = Settings> extends FrozenProcessor<P> {
    * @typeParam S Plugin settings
    */
   use<S extends any[] = [Settings?]>(
-    pluginTuple: PluginTuple<S, P>
+    pluginTuple: PluginTuple<S, P> | [Plugin<S, P>, boolean]
   ): Processor<P>
 
   /**
@@ -221,10 +221,7 @@ export interface FrozenProcessor<P = Settings> {
  * @typeParam P Processor settings
  * @returns Optional Transformer.
  */
-export type Plugin<
-  S extends any[] = [Settings?],
-  P = Settings
-> = Attacher<S, P>
+export type Plugin<S extends any[] = [Settings?], P = Settings> = Attacher<S, P>
 
 /**
  * Configuration passed to a Plugin or Processor
@@ -259,10 +256,10 @@ export interface ProcessorSettings<P = Settings> {
  * @typeParam S Plugin settings
  * @typeParam P Processor settings
  */
-export type PluginTuple<
-  S extends any[] = [Settings?],
-  P = Settings
-> = [Plugin<S, P>, ...S]
+export type PluginTuple<S extends any[] = [Settings?], P = Settings> = [
+  Plugin<S, P>,
+  ...S
+]
 
 /**
  * A union of the different ways to add plugins to unified

types/unified-tests.ts

@@ -79,6 +79,8 @@ processor.use([
 ])
 processor.use(plugin, true)
 processor.use(plugin, false)
+processor.use([plugin, true])
+processor.use([plugin, false])
 processor.use([
   [plugin, true],
   [plugin, false]
@@ -124,6 +126,14 @@ processor.use([typedPlugin, typedSetting])
 processor.use([typedPlugin, typedSetting, settings])
 // $ExpectError
 processor.use([typedPlugin, settings])
+processor.use(typedPlugin, true)
+processor.use(typedPlugin, false)
+processor.use([typedPlugin, true])
+processor.use([typedPlugin, false])
+processor.use([
+  [typedPlugin, true],
+  [typedPlugin, false]
+])
 
 processor.use(implicitlyTypedPlugin)
 processor.use(implicitlyTypedPlugin).use(implicitlyTypedPlugin)