Remove ancient undocument support for listItemIndent: 1

Author: wooorm

lib/util/check-list-item-indent.js

@@ -10,12 +10,6 @@
 export function checkListItemIndent(state) {
   const style = state.options.listItemIndent || 'tab'
 
-  // To do: remove in a major.
-  // @ts-expect-error: deprecated.
-  if (style === 1 || style === '1') {
-    return 'one'
-  }
-
   if (style !== 'tab' && style !== 'one' && style !== 'mixed') {
     throw new Error(
       'Cannot serialize items with `' +

test/index.js

@@ -3249,28 +3249,6 @@ test('listItem', async function (t) {
     }
   )
 
-  await t.test(
-    'should use one space after the bullet for `listItemIndent: "1"` (deprecated)',
-    async function () {
-      assert.equal(
-        to(
-          {
-            type: 'listItem',
-            children: [
-              {type: 'paragraph', children: [{type: 'text', value: 'a'}]},
-              {type: 'thematicBreak'}
-            ]
-          },
-          {
-            // @ts-expect-error: check how the runtime handles `listItemIdent` being wrong.
-            listItemIndent: '1'
-          }
-        ),
-        '* a\n\n  ***\n'
-      )
-    }
-  )
-
   await t.test(
     'should use one space after the bullet for `listItemIndent: "mixed"`, when the item is not spread',
     async function () {