in SSR, adjust spread with boolean attributes (sveltejs#2916)

Author: Conduitry

src/compiler/compile/render_ssr/handlers/Element.ts

@@ -1,52 +1,12 @@
 import { is_void } from '../../../utils/names';
 import { get_attribute_value, get_class_attribute_value } from './shared/get_attribute_value';
 import { get_slot_scope } from './shared/get_slot_scope';
+import { boolean_attributes } from './shared/boolean_attributes';
 import Renderer, { RenderOptions } from '../Renderer';
 import Element from '../../nodes/Element';
 import { x } from 'code-red';
 import Expression from '../../nodes/shared/Expression';
 
-// source: https://gist.github.com/ArjanSchouten/0b8574a6ad7f5065a5e7
-const boolean_attributes = new Set([
-	'async',
-	'autocomplete',
-	'autofocus',
-	'autoplay',
-	'border',
-	'challenge',
-	'checked',
-	'compact',
-	'contenteditable',
-	'controls',
-	'default',
-	'defer',
-	'disabled',
-	'formnovalidate',
-	'frameborder',
-	'hidden',
-	'indeterminate',
-	'ismap',
-	'loop',
-	'multiple',
-	'muted',
-	'nohref',
-	'noresize',
-	'noshade',
-	'novalidate',
-	'nowrap',
-	'open',
-	'readonly',
-	'required',
-	'reversed',
-	'scoped',
-	'scrolling',
-	'seamless',
-	'selected',
-	'sortable',
-	'spellcheck',
-	'translate'
-]);
-
 export default function(node: Element, renderer: Renderer, options: RenderOptions & {
 	slot_scopes: Map<any, any>;
 }) {

src/compiler/compile/render_ssr/handlers/shared/boolean_attributes.ts

@@ -0,0 +1,27 @@
+// source: https://html.spec.whatwg.org/multipage/indices.html
+export const boolean_attributes = new Set([
+	'allowfullscreen',
+	'allowpaymentrequest',
+	'async',
+	'autofocus',
+	'autoplay',
+	'checked',
+	'controls',
+	'default',
+	'defer',
+	'disabled',
+	'formnovalidate',
+	'hidden',
+	'ismap',
+	'loop',
+	'multiple',
+	'muted',
+	'nomodule',
+	'novalidate',
+	'open',
+	'playsinline',
+	'readonly',
+	'required',
+	'reversed',
+	'selected'
+]);

src/runtime/internal/ssr.ts

@@ -1,5 +1,6 @@
 import { set_current_component, current_component } from './lifecycle';
 import { run_all, blank_object } from './utils';
+import { boolean_attributes } from '../../compiler/compile/render_ssr/handlers/shared/boolean_attributes';
 
 export const invalid_attribute_name_character = /[\s'">/=\u{FDD0}-\u{FDEF}\u{FFFE}\u{FFFF}\u{1FFFE}\u{1FFFF}\u{2FFFE}\u{2FFFF}\u{3FFFE}\u{3FFFF}\u{4FFFE}\u{4FFFF}\u{5FFFE}\u{5FFFF}\u{6FFFE}\u{6FFFF}\u{7FFFE}\u{7FFFF}\u{8FFFE}\u{8FFFF}\u{9FFFE}\u{9FFFF}\u{AFFFE}\u{AFFFF}\u{BFFFE}\u{BFFFF}\u{CFFFE}\u{CFFFF}\u{DFFFE}\u{DFFFF}\u{EFFFE}\u{EFFFF}\u{FFFFE}\u{FFFFF}\u{10FFFE}\u{10FFFF}]/u;
 // https://html.spec.whatwg.org/multipage/syntax.html#attributes-2
@@ -20,14 +21,14 @@ export function spread(args, classes_to_add) {
 		if (invalid_attribute_name_character.test(name)) return;
 
 		const value = attributes[name];
-		if (value == null) return;
 		if (value === true) str += " " + name;
-
-		const escaped = String(value)
-			.replace(/"/g, '"')
-			.replace(/'/g, ''');
-
-		str += " " + name + "=" + JSON.stringify(escaped);
+		else if (boolean_attributes.has(name.toLowerCase())) {
+			if (value) str += " " + name;
+		} else if (value != null) {
+			str += " " + name + "=" + JSON.stringify(String(value)
+				.replace(/"/g, '"')
+				.replace(/'/g, '''));
+		}
 	});
 
 	return str;