Make $capture_state capture local state

src/compiler/compile/render_dom/index.ts

@@ -1,7 +1,7 @@
 import { b, x, p } from 'code-red';
 import Component from '../Component';
 import Renderer from './Renderer';
-import { CompileOptions } from '../../interfaces';
+import { CompileOptions, Var } from '../../interfaces';
 import { walk } from 'estree-walker';
 import { extract_names } from '../utils/scope';
 import { invalidate } from './invalidate';
@@ -91,7 +91,7 @@ export default function dom(
 	const accessors = [];
 
 	const not_equal = component.component_options.immutable ? x`@not_equal` : x`@safe_not_equal`;
-	let dev_props_check; let inject_state; let capture_state;
+	let dev_props_check; let inject_state: Expression; let capture_state: Expression;
 
 	props.forEach(prop => {
 		const variable = component.var_lookup.get(prop.name);
@@ -164,27 +164,41 @@ export default function dom(
 			`;
 		}
 
-		capture_state = (uses_props || writable_props.length > 0) ? x`
-			() => {
-				return { ${component.vars.filter(prop => prop.writable).map(prop => p`${prop.name}`)} };
-			}
-		` : x`
-			() => {
-				return {};
-			}
-		`;
+		// we need to filter out store subscriptions ($x) or $inject_state will try to call .set() on them, leading
+		// to a crash if store is not writable (and probably not intended behaviour to change store value)
+		const is_not_sub = (variable: Var) => variable.name.substr(0, 1) !== '$';
 
-		const writable_vars = component.vars.filter(variable => !variable.module && variable.writable);
-		inject_state = (uses_props || writable_vars.length > 0) ? x`
-			${$$props} => {
-				${uses_props && renderer.invalidate('$$props', x`$$props = @assign(@assign({}, $$props), $$new_props)`)}
-				${writable_vars.map(prop => b`
-					if ('${prop.name}' in $$props) ${renderer.invalidate(prop.name, x`${prop.name} = ${$$props}.${prop.name}`)};
-				`)}
-			}
-		` : x`
-			${$$props} => {}
-		`;
+		const capturable_vars = component.vars.filter(
+			variable => !variable.module && variable.writable && is_not_sub(variable)
+		);
+
+		if (uses_props || capturable_vars.length > 0) {
+
+			const capturable_props = writable_props.filter(is_not_sub);
+
+			const local_vars = capturable_vars.filter(variable => !variable.export_name);
+
+			const var_names = (variables: Var[]) => variables.map(prop => p`${prop.name}`);
+
+			capture_state = x`
+				({ props: $p = true, local: $l = true } = {}) => ({
+					...${x`$p && { ${var_names(capturable_props)} }`},
+					...${x`$l && { ${var_names(local_vars)} }`}
+				})
+			`;
+
+			inject_state = x`
+				${$$props} => {
+					${uses_props && renderer.invalidate('$$props', x`$$props = @assign(@assign({}, $$props), $$new_props)`)}
+					${capturable_vars.map(prop => b`
+						if ('${prop.name}' in $$props) ${renderer.invalidate(prop.name, x`${prop.name} = ${$$props}.${prop.name}`)};
+					`)}
+				}
+			`;
+		} else {
+			capture_state = x`() => ({})`;
+			inject_state = x`() => {}`;
+		}
 	}
 
 	// instrument assignments

test/js/samples/capture-inject-state/_config.js

@@ -0,0 +1,5 @@
+export default {
+	options: {
+		dev: true
+	}
+};

test/js/samples/capture-inject-state/expected.js

@@ -0,0 +1,158 @@
+/* generated by Svelte vX.Y.Z */
+import {
+	SvelteComponentDev,
+	add_location,
+	append_dev,
+	detach_dev,
+	dispatch_dev,
+	element,
+	init,
+	insert_dev,
+	noop,
+	safe_not_equal,
+	set_data_dev,
+	space,
+	subscribe,
+	text,
+	validate_store
+} from "svelte/internal";
+
+const file = undefined;
+
+function create_fragment(ctx) {
+	let p;
+	let t0;
+	let t1;
+	let t2;
+	let t3;
+	let t4;
+	let t5;
+	let t6;
+
+	const block = {
+		c: function create() {
+			p = element("p");
+			t0 = text(/*$prop*/ ctx[1]);
+			t1 = space();
+			t2 = text(/*realName*/ ctx[0]);
+			t3 = space();
+			t4 = text(/*local*/ ctx[2]);
+			t5 = space();
+			t6 = text(priv);
+			add_location(p, file, 11, 0, 204);
+		},
+		l: function claim(nodes) {
+			throw new Error("options.hydrate only works if the component was compiled with the `hydratable: true` option");
+		},
+		m: function mount(target, anchor) {
+			insert_dev(target, p, anchor);
+			append_dev(p, t0);
+			append_dev(p, t1);
+			append_dev(p, t2);
+			append_dev(p, t3);
+			append_dev(p, t4);
+			append_dev(p, t5);
+			append_dev(p, t6);
+		},
+		p: function update(ctx, [dirty]) {
+			if (dirty & /*$prop*/ 2) set_data_dev(t0, /*$prop*/ ctx[1]);
+			if (dirty & /*realName*/ 1) set_data_dev(t2, /*realName*/ ctx[0]);
+		},
+		i: noop,
+		o: noop,
+		d: function destroy(detaching) {
+			if (detaching) detach_dev(p);
+		}
+	};
+
+	dispatch_dev("SvelteRegisterBlock", {
+		block,
+		id: create_fragment.name,
+		type: "component",
+		source: "",
+		ctx
+	});
+
+	return block;
+}
+
+const priv = "priv";
+
+function instance($$self, $$props, $$invalidate) {
+	let $prop,
+		$$unsubscribe_prop = noop,
+		$$subscribe_prop = () => ($$unsubscribe_prop(), $$unsubscribe_prop = subscribe(prop, $$value => $$invalidate(1, $prop = $$value)), prop);
+
+	$$self.$$.on_destroy.push(() => $$unsubscribe_prop());
+	let { prop } = $$props;
+	validate_store(prop, "prop");
+	$$subscribe_prop();
+	let { alias: realName } = $$props;
+	let local;
+	const writable_props = ["prop", "alias"];
+
+	Object.keys($$props).forEach(key => {
+		if (!~writable_props.indexOf(key) && key.slice(0, 2) !== "$$") console.warn(`<Component> was created with unknown prop '${key}'`);
+	});
+
+	$$self.$set = $$props => {
+		if ("prop" in $$props) $$subscribe_prop($$invalidate(3, prop = $$props.prop));
+		if ("alias" in $$props) $$invalidate(0, realName = $$props.alias);
+	};
+
+	$$self.$capture_state = ({ props: $p = true, local: $l = true } = {}) => ({
+		...$p && ({ prop, realName }),
+		...$l && ({ local })
+	});
+
+	$$self.$inject_state = $$props => {
+		if ("prop" in $$props) $$subscribe_prop($$invalidate(3, prop = $$props.prop));
+		if ("realName" in $$props) $$invalidate(0, realName = $$props.realName);
+		if ("local" in $$props) $$invalidate(2, local = $$props.local);
+	};
+
+	return [realName, $prop, local, prop];
+}
+
+class Component extends SvelteComponentDev {
+	constructor(options) {
+		super(options);
+		init(this, options, instance, create_fragment, safe_not_equal, { prop: 3, alias: 0 });
+
+		dispatch_dev("SvelteRegisterComponent", {
+			component: this,
+			tagName: "Component",
+			options,
+			id: create_fragment.name
+		});
+
+		const { ctx } = this.$$;
+		const props = options.props || ({});
+
+		if (/*prop*/ ctx[3] === undefined && !("prop" in props)) {
+			console.warn("<Component> was created without expected prop 'prop'");
+		}
+
+		if (/*realName*/ ctx[0] === undefined && !("alias" in props)) {
+			console.warn("<Component> was created without expected prop 'alias'");
+		}
+	}
+
+	get prop() {
+		throw new Error("<Component>: Props cannot be read directly from the component instance unless compiling with 'accessors: true' or '<svelte:options accessors/>'");
+	}
+
+	set prop(value) {
+		throw new Error("<Component>: Props cannot be set directly on the component instance unless compiling with 'accessors: true' or '<svelte:options accessors/>'");
+	}
+
+	get alias() {
+		throw new Error("<Component>: Props cannot be read directly from the component instance unless compiling with 'accessors: true' or '<svelte:options accessors/>'");
+	}
+
+	set alias(value) {
+		throw new Error("<Component>: Props cannot be set directly on the component instance unless compiling with 'accessors: true' or '<svelte:options accessors/>'");
+	}
+}
+
+export default Component;

test/js/samples/capture-inject-state/input.svelte

@@ -0,0 +1,12 @@
+<script>
+  export let prop;
+
+  let realName;
+  export { realName as alias };
+
+  let local;
+
+  const priv = 'priv';
+</script>
+<!-- NOTE $prop ensures store subscriptions are not part of captured state -->
+<p>{$prop} {realName} {local} {priv}</p>

test/js/samples/debug-empty/expected.js

@@ -79,9 +79,7 @@ function instance($$self, $$props, $$invalidate) {
 		if ("name" in $$props) $$invalidate(0, name = $$props.name);
 	};
 
-	$$self.$capture_state = () => {
-		return { name };
-	};
+	$$self.$capture_state = ({ props: $p = true, local: $l = true } = {}) => ({ ...$p && ({ name }), ...$l && ({}) });
 
 	$$self.$inject_state = $$props => {
 		if ("name" in $$props) $$invalidate(0, name = $$props.name);

test/js/samples/debug-foo-bar-baz-things/expected.js

@@ -183,9 +183,10 @@ function instance($$self, $$props, $$invalidate) {
 		if ("baz" in $$props) $$invalidate(3, baz = $$props.baz);
 	};
 
-	$$self.$capture_state = () => {
-		return { things, foo, bar, baz };
-	};
+	$$self.$capture_state = ({ props: $p = true, local: $l = true } = {}) => ({
+		...$p && ({ things, foo, bar, baz }),
+		...$l && ({})
+	});
 
 	$$self.$inject_state = $$props => {
 		if ("things" in $$props) $$invalidate(0, things = $$props.things);

test/js/samples/debug-foo/expected.js

@@ -173,9 +173,10 @@ function instance($$self, $$props, $$invalidate) {
 		if ("foo" in $$props) $$invalidate(1, foo = $$props.foo);
 	};
 
-	$$self.$capture_state = () => {
-		return { things, foo };
-	};
+	$$self.$capture_state = ({ props: $p = true, local: $l = true } = {}) => ({
+		...$p && ({ things, foo }),
+		...$l && ({})
+	});
 
 	$$self.$inject_state = $$props => {
 		if ("things" in $$props) $$invalidate(0, things = $$props.things);

test/js/samples/debug-hoisted/expected.js

@@ -51,9 +51,10 @@ function instance($$self) {
 	let obj = { x: 5 };
 	let kobzol = 5;
 
-	$$self.$capture_state = () => {
-		return {};
-	};
+	$$self.$capture_state = ({ props: $p = true, local: $l = true } = {}) => ({
+		...$p && ({}),
+		...$l && ({ obj, kobzol })
+	});
 
 	$$self.$inject_state = $$props => {
 		if ("obj" in $$props) $$invalidate(0, obj = $$props.obj);

test/js/samples/dev-warning-missing-data-computed/expected.js

@@ -76,9 +76,7 @@ function instance($$self, $$props, $$invalidate) {
 		if ("foo" in $$props) $$invalidate(0, foo = $$props.foo);
 	};
 
-	$$self.$capture_state = () => {
-		return { foo, bar };
-	};
+	$$self.$capture_state = ({ props: $p = true, local: $l = true } = {}) => ({ ...$p && ({ foo }), ...$l && ({ bar }) });
 
 	$$self.$inject_state = $$props => {
 		if ("foo" in $$props) $$invalidate(0, foo = $$props.foo);

test/js/samples/loop-protect/expected.js

@@ -63,11 +63,9 @@ function instance($$self) {
 		guard_4();
 	} while (true);
 
-	$$self.$capture_state = () => {
-		return {};
-	};
+	$$self.$capture_state = () => ({});
 
-	$$self.$inject_state = $$props => {
+	$$self.$inject_state = () => {
 
 	};
 
@@ -106,4 +104,4 @@ class Component extends SvelteComponentDev {
 	}
 }
 
-export default Component;
+export default Component;