(fix) handle action on svelte:body (#1170)

Narrows the type to HTMLBodyElement

Author: dummdidumm

packages/svelte2tsx/src/htmlxtojsx/nodes/action-directive.ts

@@ -12,16 +12,17 @@ export function handleActionDirective(
     parent: BaseNode
 ): void {
     str.overwrite(attr.start, attr.start + 'use:'.length, '{...__sveltets_1_ensureAction(');
+    const name = parent.name === 'svelte:body' ? 'body' : parent.name;
 
     if (!attr.expression) {
-        str.appendLeft(attr.end, `(__sveltets_1_mapElementTag('${parent.name}')))}`);
+        str.appendLeft(attr.end, `(__sveltets_1_mapElementTag('${name}')))}`);
         return;
     }
 
     str.overwrite(
         attr.start + `use:${attr.name}`.length,
         attr.expression.start,
-        `(__sveltets_1_mapElementTag('${parent.name}'),(`
+        `(__sveltets_1_mapElementTag('${name}'),(`
     );
     str.appendLeft(attr.expression.end, ')))');
     const lastChar = htmlx[attr.end - 1];

packages/svelte2tsx/test/htmlx2jsx/samples/action-svelte-body/expected.jsx

@@ -0,0 +1 @@
+<><sveltebody {...__sveltets_1_ensureAction(blink(__sveltets_1_mapElementTag('body')))} /></>

packages/svelte2tsx/test/htmlx2jsx/samples/action-svelte-body/input.svelte

@@ -0,0 +1 @@
+<svelte:body use:blink />