support sapper-noscroll (#438)

* support sapper-noscroll

* fix typo and tweak

Author: jasonlyu123

packages/svelte2tsx/src/htmlxtojsx/index.ts

@@ -355,13 +355,14 @@ export function convertHtmlxToJsx(
         //if we are on an "element" we are case insensitive, lowercase to match our JSX
         if (parent.type == 'Element') {
             //skip Attribute shorthand, that is handled below
+            const sapperNoScroll = attr.name === 'sapper:noscroll';
             if (
                 attr.value !== true &&
                 !(
                     attr.value.length &&
                     attr.value.length == 1 &&
                     attr.value[0].type == 'AttributeShorthand'
-                )
+                ) || sapperNoScroll
             ) {
                 let name = attr.name;
                 if (!svgAttributes.find((x) => x == name)) {

packages/svelte2tsx/svelte-jsx.d.ts

@@ -697,9 +697,13 @@
       onrejectionhandled?: EventHandler<PromiseRejectionEvent, Window>;
     }
 
+    interface SapperAnchorProps {
+        sapperNoscroll?: true;
+    }
+
     interface IntrinsicElements {
       // HTML
-      a: HTMLProps<HTMLAnchorElement>;
+      a: HTMLProps<HTMLAnchorElement> & SapperAnchorProps;
       abbr: HTMLProps<HTMLElement>;
       address: HTMLProps<HTMLElement>;
       area: HTMLProps<HTMLAreaElement>;

packages/svelte2tsx/test/htmlx2jsx/samples/sapper-noscroll/expected.jsx

@@ -0,0 +1 @@
+<><a sapperNoscroll></a></>

packages/svelte2tsx/test/htmlx2jsx/samples/sapper-noscroll/input.svelte

@@ -0,0 +1 @@
+<a sapper:noscroll></a>