Change to yield undefined

Author: wooorm

lib/index.js

@@ -5,22 +5,19 @@
 import {headingRank} from 'hast-util-heading-rank'
 import {visit} from 'unist-util-visit'
 
-// To do next major: don’t return node.
 /**
  * Change the rank of all headings (`h1` to `h6`) in `tree`.
  *
  * Mutates the tree.
  * Caps the rank so that shifting would not create invalid headings (so no `h0` or
  * `h7`).
  *
- * @template {Nodes} T
- *   Node type.
- * @param {T} tree
+ * @param {Nodes} tree
  *   Tree to change.
  * @param {number} shift
  *   Non-null finite integer to use to shift ranks.
- * @returns {T}
- *   Given, modified, tree.
+ * @returns {undefined}
+ *   Nothing.
  * @throws
  *   When `shift` is not a valid non-null finite integer.
  */
@@ -42,6 +39,4 @@ export function shiftHeading(tree, shift) {
       node.tagName = 'h' + (rank > 6 ? 6 : rank < 1 ? 1 : rank)
     }
   })
-
-  return tree
 }

readme.md

@@ -140,7 +140,7 @@ Caps the rank so that shifting would not create invalid headings (so no `h0` or
 
 ###### Returns
 
-Given, modified, tree ([`Node`][node]).
+Nothing (`undefined`).
 
 ###### Throws
 

test.js

@@ -48,27 +48,38 @@ test('shiftHeading', async function (t) {
   )
 
   await t.test('should shift nodes upwards', async function () {
-    assert.deepEqual(shiftHeading(h('h1', 'Alpha'), 1), h('h2', 'Alpha'))
+    const tree = h('h1', 'Alpha')
+    shiftHeading(tree, 1)
+    assert.deepEqual(tree, h('h2', 'Alpha'))
   })
 
   await t.test('should shift nodes downwards', async function () {
-    assert.deepEqual(shiftHeading(h('h2', 'Bravo'), -1), h('h1', 'Bravo'))
+    const tree = h('h2', 'Bravo')
+    shiftHeading(tree, -1)
+    assert.deepEqual(tree, h('h1', 'Bravo'))
   })
 
   await t.test('should not shift upwards past h1', async function () {
-    assert.deepEqual(shiftHeading(h('h2', 'Charlie'), -2), h('h1', 'Charlie'))
+    const tree = h('h2', 'Charlie')
+    shiftHeading(tree, -2)
+    assert.deepEqual(tree, h('h1', 'Charlie'))
   })
 
   await t.test('should not shift downwards past h6', async function () {
-    assert.deepEqual(shiftHeading(h('h5', 'Delta'), 2), h('h6', 'Delta'))
+    const tree = h('h5', 'Delta')
+    shiftHeading(tree, 2)
+    assert.deepEqual(tree, h('h6', 'Delta'))
   })
 
   await t.test('should change a tree', async function () {
+    const tree = h('main', [
+      h('h1', 'Echo'),
+      h('p', 'Foxtrot'),
+      h('h5', 'Golf')
+    ])
+    shiftHeading(tree, 2)
     assert.deepEqual(
-      shiftHeading(
-        h('main', [h('h1', 'Echo'), h('p', 'Foxtrot'), h('h5', 'Golf')]),
-        2
-      ),
+      tree,
       h('main', [h('h3', 'Echo'), h('p', 'Foxtrot'), h('h6', 'Golf')])
     )
   })