From db5ea4657fe9ce0d241f8cc0a7e08e254e6b7739 Mon Sep 17 00:00:00 2001
From: Titus Wormer <tituswormer@gmail.com>
Date: Mon, 7 Aug 2023 15:50:51 +0200
Subject: [PATCH] Change to yield `undefined`

---
 lib/index.js   | 10 ++++------
 readme.md      |  3 ++-
 test/select.js | 26 +++++++++++++-------------
 test/svg.js    |  2 +-
 4 files changed, 20 insertions(+), 21 deletions(-)

diff --git a/lib/index.js b/lib/index.js
index 1cd11af..45a4b47 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -87,17 +87,15 @@ export function matches(selector, node, space) {
  *   Tree to search (optional).
  * @param {Space | null | undefined} [space='html']
  *   Name of namespace (default: `'html'`).
- * @returns {Element | null}
- *   First element in `tree` that matches `selector` or `null` if nothing is
- *   found.
- *   This could be `tree` itself.
+ * @returns {Element | undefined}
+ *   First element in `tree` that matches `selector` or `undefined` if nothing
+ *   is found; this could be `tree` itself.
  */
 export function select(selector, tree, space) {
   const state = createState(selector, tree, space)
   state.one = true
   walk(state, tree || undefined)
-  // To do in major: return `undefined` instead.
-  return state.results[0] || null
+  return state.results[0]
 }
 
 /**
diff --git a/readme.md b/readme.md
index ceef9fd..d58b178 100644
--- a/readme.md
+++ b/readme.md
@@ -160,7 +160,8 @@ Searches the tree in *[preorder][]*.
 
 ###### Returns
 
-First element in `tree` that matches `selector` or `null` if nothing is found.
+First element in `tree` that matches `selector` or `undefined` if nothing is
+found.
 This could be `tree` itself.
 
 ###### Example
diff --git a/test/select.js b/test/select.js
index 6f7655b..a4628be 100644
--- a/test/select.js
+++ b/test/select.js
@@ -74,13 +74,13 @@ test('select.select()', async function (t) {
     )
 
     await t.test('should not select if not given a node', async function () {
-      assert.equal(select('*'), null)
+      assert.equal(select('*'), undefined)
     })
 
     await t.test(
       'should not select if not given an element',
       async function () {
-        assert.equal(select('*', {type: 'text', value: 'a'}), null)
+        assert.equal(select('*', {type: 'text', value: 'a'}), undefined)
       }
     )
 
@@ -219,7 +219,7 @@ test('select.select()', async function (t) {
             h('p', 'Delta')
           ])
         ),
-        null
+        undefined
       )
     })
   })
@@ -290,7 +290,7 @@ test('select.select()', async function (t) {
           'h1 ~ p',
           u('root', [h('p', 'Alpha'), h('h1', 'Bravo'), h('h2', 'Charlie')])
         ),
-        null
+        undefined
       )
     })
   })
@@ -321,7 +321,7 @@ test('select.select()', async function (t) {
               'h1:first-child',
               u('root', [h('p', 'Alpha'), h('h1', 'Bravo'), h('p', 'Charlie')])
             ),
-            null
+            undefined
           )
         }
       )
@@ -352,7 +352,7 @@ test('select.select()', async function (t) {
               'h1:last-child',
               u('root', [h('p', 'Alpha'), h('h1', 'Bravo'), h('p', 'Charlie')])
             ),
-            null
+            undefined
           )
         }
       )
@@ -383,7 +383,7 @@ test('select.select()', async function (t) {
               'h1:only-child',
               u('root', [h('p', 'Alpha'), h('h1', 'Bravo'), h('p', 'Charlie')])
             ),
-            null
+            undefined
           )
         }
       )
@@ -739,7 +739,7 @@ test('select.select()', async function (t) {
       )
 
       await t.test('should return nothing without matches', async function () {
-        assert.equal(select('dt:first-of-type', h('dl', [])), null)
+        assert.equal(select('dt:first-of-type', h('dl', [])), undefined)
       })
     })
 
@@ -765,7 +765,7 @@ test('select.select()', async function (t) {
       )
 
       await t.test('should return nothing without matches', async function () {
-        assert.equal(select('dt:last-of-type', h('dl', [])), null)
+        assert.equal(select('dt:last-of-type', h('dl', [])), undefined)
       })
     })
 
@@ -800,13 +800,13 @@ test('select.select()', async function (t) {
                 h('dd', 'Foxtrot')
               ])
             ),
-            null
+            undefined
           )
         }
       )
 
       await t.test('should return nothing without matches', async function () {
-        assert.equal(select('dt:only-of-type', h('dl', [])), null)
+        assert.equal(select('dt:only-of-type', h('dl', [])), undefined)
       })
     })
   })
@@ -885,7 +885,7 @@ test('select.select()', async function (t) {
               ])
             ])
           ),
-          null
+          undefined
         )
       }
     )
@@ -900,7 +900,7 @@ test('select.select()', async function (t) {
             'p:read-only',
             u('root', [h('div', {contentEditable: 'true'}, [h('p', 'A')])])
           ),
-          null
+          undefined
         )
       }
     )
diff --git a/test/svg.js b/test/svg.js
index 18fe786..ec10113 100644
--- a/test/svg.js
+++ b/test/svg.js
@@ -46,7 +46,7 @@ test('svg', async function (t) {
   await t.test('should match svg (#3)', async function () {
     assert.deepEqual(
       select('[writing-mode]', s('text', {writingMode: 'lr-tb'}, '!')),
-      null
+      undefined
     )
   })