fix linting messages when using write-only store (#108)

src/preprocess.js

@@ -63,7 +63,7 @@ export const preprocess = text => {
 	}
 	const { ast, warnings, vars, mapper } = result;
 
-	const references_and_reassignments = `{${vars.filter(v => v.referenced).map(v => v.name)};${vars.filter(v => v.reassigned || v.export_name).map(v => v.name + '=0')}}`;
+	const references_and_reassignments = `{${vars.filter(v => v.referenced || v.name[0] === '$').map(v => v.name)};${vars.filter(v => v.reassigned || v.export_name).map(v => v.name + '=0')}}`;
 	state.var_names = new Set(vars.map(v => v.name));
 
 	// convert warnings to linting messages
@@ -184,7 +184,7 @@ export const preprocess = text => {
 			},
 		});
 
-		block.transformed_code += `{${vars.filter(v => v.referenced_from_script).map(v => v.name)}}`;
+		block.transformed_code += `{${vars.filter(v => v.referenced_from_script || v.name[0] === '$').map(v => v.name)}}`;
 	}
 
 	// return processed string

test/samples/unused-write-only-store/.eslintrc.js

@@ -0,0 +1,5 @@
+module.exports = {
+	rules: {
+		"no-unused-vars": "error",
+	},
+};

test/samples/unused-write-only-store/Input.svelte

@@ -0,0 +1,12 @@
+<script>
+	import { imported, createStore } from './store.js';
+
+	const writeOnly = createStore();
+	$writeOnly = 99;
+
+	const readOnly = createStore();
+	$readOnly;
+
+	$imported = 'some value';
+</script>
+<div on:click={() => $imported = 'clicked' }/>

test/samples/unused-write-only-store/expected.json

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