[fix] add injected globals to ts when there's no instance script

Fixes sveltejs#152
Fixes sveltejs#107
Fixes sveltejs#152

Author: Simon Holthausen

src/preprocess.js

@@ -147,9 +147,11 @@ export const preprocess = text => {
 			if (ast.module) {
 				block.transformed_code += text.slice(ast.module.content.start, ast.module.content.end);
 			}
-			if (ast.instance) {
+			if (ast.instance || vars.length) {
 				block.transformed_code += '\n';
-				block.transformed_code += vars.filter(v => v.injected).map(v => tsLet(v.name)).join('');
+			}
+			block.transformed_code += vars.filter(v => v.injected).map(v => tsLet(v.name)).join('');
+			if (ast.instance) {
 				block.transformed_code += text.slice(ast.instance.content.start, ast.instance.content.end);
 			}
 		} else {

test/samples/typescript-$$globals/.eslintrc.js

@@ -0,0 +1,8 @@
+module.exports = {
+	parser: '@typescript-eslint/parser',
+	extends: ['eslint:recommended', 'plugin:@typescript-eslint/recommended'],
+	plugins: ['@typescript-eslint'],
+	settings: {
+		'svelte3/typescript': require('typescript'),
+	},
+};

test/samples/typescript-$$globals/Input.svelte

@@ -0,0 +1,3 @@
+{$$slots.foo}
+{$$props.bar}
+{$$restProps.baz}

test/samples/typescript-$$globals/expected.json

@@ -0,0 +1 @@
+[]