[draft] Spell check custom dictionary

source

@@ -87520,6 +87520,93 @@ body { display:none }
   checkers. A user agent could offer on-demand checking, could perform continuous checking while the
   checking is enabled, or could use other interfaces.</p>
 
+  <h4>Custom spelling dictionary</h4>
+
+  <p>Each <code>Document</code> has a <dfn data-x="concept-custom-spelling-exemptions">custom
+  spelling exemption list</dfn>, which is an <span data-x="set">ordered set</span> of strings, initially empty.</p>
+
+  <p>If the checking is enabled for a word and that word is a match for any entry in the element's <span>node document</span>'s <span
+  data-x="concept-custom-spelling-exemptions">custom spelling exemption list</span>, the user agent
+  should not indicate a spelling error for that word.</p>
+
+
+  <p class="note">The custom spelling exemption list is not persisted, is not shared across
+  documents, frames, or browsing contexts, and is discarded when the <code>Document</code> is
+  destroyed.</p>
+
+  <p class="note">Entries are matched against individual words as identified by the user agent's
+  spell checking algorithm. Entries containing whitespace or other word separators will generally
+  not match any word and will have no effect.</p>
+
+  <p class="note">Entries are matched exactly. Authors might need to add multiple forms of a word —
+  for example, both "anaerobe" and "anaerobes" — to exempt all variants from spell checking.</p>
+
+  <dl class="domintro">
+   <dt><code data-x=""><var>window</var>.<span subdfn data-x="dom-window-spellCheckDictionary">spellCheckDictionary</span>.addWords(<var>words</var>)</code></dt>
+   <dd>
+    <p>Adds each string in <var>words</var> to the <span
+    data-x="concept-custom-spelling-exemptions">custom spelling exemption list</span> of this
+    window's associated document. Words already present are ignored.</p>
+   </dd>
+
+   <dt><code data-x=""><var>window</var>.<span data-x="dom-window-spellCheckDictionary">spellCheckDictionary</span>.removeWords(<var>words</var>)</code></dt>
+   <dd>
+    <p>Removes each string in <var>words</var> from the <span
+    data-x="concept-custom-spelling-exemptions">custom spelling exemption list</span> of this
+    window's associated document. Words not present are ignored.</p>
+   </dd>
+  </dl>
+
+  <div w-nodev>
+
+  <p>User agents that do not support spell checking must not expose the <code
+  data-x="dom-window-spellCheckDictionary">spellCheckDictionary</code> attribute on the
+  <code>Window</code> object.</p>
+
+  <p>The <dfn attribute for="Window"><code
+  data-x="dom-window-spellCheckDictionary">spellCheckDictionary</code></dfn> attribute must return
+  the <code>SpellCheckCustomDictionary</code> object associated with <span>this</span>'s <span>relevant
+  global object</span>'s <span data-x="concept-document-window">associated
+  <code>Document</code></span>, creating one if it does not yet exist.</p>
+
+  <p>The following interface is defined for the custom spelling dictionary:</p>
+
+  <pre class="idl">[Exposed=<span>Window</span>, SecureContext]
+interface <dfn>SpellCheckCustomDictionary</dfn> {
+  undefined <span data-x="dom-SpellCheckCustomDictionary-addWords">addWords</span>(sequence&lt;DOMString> words);
+  undefined <span data-x="dom-SpellCheckCustomDictionary-removeWords">removeWords</span>(sequence&lt;DOMString> words);
+};</pre>
+
+  <div algorithm>
+  <p>The <dfn method for="SpellCheckCustomDictionary"><code
+  data-x="dom-SpellCheckCustomDictionary-addWords">addWords(<var>words</var>)</code></dfn> method
+  steps are:</p>
+  <ol>
+   <li><p>Let <var>document</var> be <span>this</span>'s <span>relevant global object</span>'s
+   <span data-x="concept-document-window">associated <code>Document</code></span>.</p></li>
+   <li><p>For each <var>word</var> in <var>words</var>: <span data-x="set append">append</span>
+   <var>word</var> to <var>document</var>'s <span
+   data-x="concept-custom-spelling-exemptions">custom spelling exemption list</span>, if
+   <var>word</var> is not already in the list.</p></li>
+  </ol>
+  </div>
+
+  <div algorithm>
+  <p>The <dfn method for="SpellCheckCustomDictionary"><code
+  data-x="dom-SpellCheckCustomDictionary-removeWords">removeWords(<var>words</var>)</code></dfn>
+  method steps are:</p>
+  <ol>
+   <li><p>Let <var>document</var> be <span>this</span>'s <span>relevant global object</span>'s
+   <span data-x="concept-document-window">associated <code>Document</code></span>.</p></li>
+   <li><p>For each <var>word</var> in <var>words</var>: <span data-x="list remove">remove</span>
+   <var>word</var> from <var>document</var>'s <span
+   data-x="concept-custom-spelling-exemptions">custom spelling exemption list</span>, if
+   present.</p></li>
+  </ol>
+  </div>
+
+  </div>
+
   <h4>Writing suggestions</h4>
 
   <p>User agents offer writing suggestions as users type into editable regions, either in form
@@ -95996,6 +96083,7 @@ interface <dfn interface>Window</dfn> : <span>EventTarget</span> {
   [PutForwards=<span data-x="dom-location-href">href</span>, <span>LegacyUnforgeable</span>] readonly attribute <span>Location</span> <span data-x="dom-location">location</span>;
   readonly attribute <span>History</span> <span data-x="dom-history">history</span>;
   [Replaceable] readonly attribute <span>Navigation</span> <span data-x="dom-navigation">navigation</span>;
+  [SecureContext, SameObject] readonly attribute <span>SpellCheckCustomDictionary</span> <span data-x="dom-window-spellCheckDictionary">spellCheckDictionary</span>;
   readonly attribute <span>CustomElementRegistry</span> <span data-x="dom-window-customElements">customElements</span>;
   [Replaceable] readonly attribute <span>BarProp</span> <span data-x="dom-window-locationbar">locationbar</span>;
   [Replaceable] readonly attribute <span>BarProp</span> <span data-x="dom-window-menubar">menubar</span>;