Repository: sveltejs/svelte (JavaScript)
Date: 2017-12-25 01:17:10+00:00
Task type: Bug Fix

Issue:
Remove whitespace nodes inside <:Head>
Whitespace is irrelevant inside `<head>`, so it should be removed.


Issue discussion:

Solution patch:
diff --git a/src/generators/nodes/Text.ts b/src/generators/nodes/Text.ts
--- a/src/generators/nodes/Text.ts
+++ b/src/generators/nodes/Text.ts
@@ -19,9 +19,10 @@ const elementsWithoutText = new Set([
 function shouldSkip(node: Text) {
 	if (/\S/.test(node.data)) return false;
 
-	const parentElement = node.findNearest(/(?:Element|Component)/);
+	const parentElement = node.findNearest(/(?:Element|Component|Head)/);
 	if (!parentElement) return false;
 
+	if (parentElement.type === 'Head') return true;
 	if (parentElement.type === 'Component') return parentElement.children.length === 1 && node === parentElement.children[0];
 
 	return parentElement.namespace || elementsWithoutText.has(parentElement.name);


Test patch:
diff --git a/test/js/samples/head-no-whitespace/expected-bundle.js b/test/js/samples/head-no-whitespace/expected-bundle.js
new file mode 100644
--- /dev/null
+++ b/test/js/samples/head-no-whitespace/expected-bundle.js
@@ -0,0 +1,231 @@
+function noop() {}
+
+function assign(target) {
+	var k,
+		source,
+		i = 1,
+		len = arguments.length;
+	for (; i < len; i++) {
+		source = arguments[i];
+		for (k in source) target[k] = source[k];
+	}
+
+	return target;
+}
+
+function appendNode(node, target) {
+	target.appendChild(node);
+}
+
+function detachNode(node) {
+	node.parentNode.removeChild(node);
+}
+
+function createElement(name) {
+	return document.createElement(name);
+}
+
+function blankObject() {
+	return Object.create(null);
+}
+
+function destroy(detach) {
+	this.destroy = noop;
+	this.fire('destroy');
+	this.set = this.get = noop;
+
+	if (detach !== false) this._fragment.u();
+	this._fragment.d();
+	this._fragment = this._state = null;
+}
+
+function differs(a, b) {
+	return a !== b || ((a && typeof a === 'object') || typeof a === 'function');
+}
+
+function dispatchObservers(component, group, changed, newState, oldState) {
+	for (var key in group) {
+		if (!changed[key]) continue;
+
+		var newValue = newState[key];
+		var oldValue = oldState[key];
+
+		var callbacks = group[key];
+		if (!callbacks) continue;
+
+		for (var i = 0; i < callbacks.length; i += 1) {
+			var callback = callbacks[i];
+			if (callback.__calling) continue;
+
+			callback.__calling = true;
+			callback.call(component, newValue, oldValue);
+			callback.__calling = false;
+		}
+	}
+}
+
+function fire(eventName, data) {
+	var handlers =
+		eventName in this._handlers && this._handlers[eventName].slice();
+	if (!handlers) return;
+
+	for (var i = 0; i < handlers.length; i += 1) {
+		handlers[i].call(this, data);
+	}
+}
+
+function get(key) {
+	return key ? this._state[key] : this._state;
+}
+
+function init(component, options) {
+	component._observers = { pre: blankObject(), post: blankObject() };
+	component._handlers = blankObject();
+	component._bind = options._bind;
+
+	component.options = options;
+	component.root = options.root || component;
+	component.store = component.root.store || options.store;
+}
+
+function observe(key, callback, options) {
+	var group = options && options.defer
+		? this._observers.post
+		: this._observers.pre;
+
+	(group[key] || (group[key] = [])).push(callback);
+
+	if (!options || options.init !== false) {
+		callback.__calling = true;
+		callback.call(this, this._state[key]);
+		callback.__calling = false;
+	}
+
+	return {
+		cancel: function() {
+			var index = group[key].indexOf(callback);
+			if (~index) group[key].splice(index, 1);
+		}
+	};
+}
+
+function on(eventName, handler) {
+	if (eventName === 'teardown') return this.on('destroy', handler);
+
+	var handlers = this._handlers[eventName] || (this._handlers[eventName] = []);
+	handlers.push(handler);
+
+	return {
+		cancel: function() {
+			var index = handlers.indexOf(handler);
+			if (~index) handlers.splice(index, 1);
+		}
+	};
+}
+
+function set(newState) {
+	this._set(assign({}, newState));
+	if (this.root._lock) return;
+	this.root._lock = true;
+	callAll(this.root._beforecreate);
+	callAll(this.root._oncreate);
+	callAll(this.root._aftercreate);
+	this.root._lock = false;
+}
+
+function _set(newState) {
+	var oldState = this._state,
+		changed = {},
+		dirty = false;
+
+	for (var key in newState) {
+		if (differs(newState[key], oldState[key])) changed[key] = dirty = true;
+	}
+	if (!dirty) return;
+
+	this._state = assign({}, oldState, newState);
+	this._recompute(changed, this._state);
+	if (this._bind) this._bind(changed, this._state);
+
+	if (this._fragment) {
+		dispatchObservers(this, this._observers.pre, changed, this._state, oldState);
+		this._fragment.p(changed, this._state);
+		dispatchObservers(this, this._observers.post, changed, this._state, oldState);
+	}
+}
+
+function callAll(fns) {
+	while (fns && fns.length) fns.pop()();
+}
+
+function _mount(target, anchor) {
+	this._fragment.m(target, anchor);
+}
+
+function _unmount() {
+	if (this._fragment) this._fragment.u();
+}
+
+var proto = {
+	destroy: destroy,
+	get: get,
+	fire: fire,
+	observe: observe,
+	on: on,
+	set: set,
+	teardown: destroy,
+	_recompute: noop,
+	_set: _set,
+	_mount: _mount,
+	_unmount: _unmount
+};
+
+/* generated by Svelte vX.Y.Z */
+function create_main_fragment(state, component) {
+	var meta, meta_1;
+
+	return {
+		c: function create() {
+			meta = createElement("meta");
+			meta_1 = createElement("meta");
+			this.h();
+		},
+
+		h: function hydrate() {
+			meta.name = "twitter:creator";
+			meta.content = "@sveltejs";
+			meta_1.name = "twitter:title";
+			meta_1.content = "Svelte";
+		},
+
+		m: function mount(target, anchor) {
+			appendNode(meta, document.head);
+			appendNode(meta_1, document.head);
+		},
+
+		p: noop,
+
+		u: function unmount() {
+			detachNode(meta);
+			detachNode(meta_1);
+		},
+
+		d: noop
+	};
+}
+
+function SvelteComponent(options) {
+	init(this, options);
+	this._state = assign({}, options.data);
+
+	this._fragment = create_main_fragment(this._state, this);
+
+	if (options.target) {
+		this._fragment.c();
+		this._fragment.m(options.target, options.anchor || null);
+	}
+}
+
+assign(SvelteComponent.prototype, proto);
+
+export default SvelteComponent;
diff --git a/test/js/samples/head-no-whitespace/expected.js b/test/js/samples/head-no-whitespace/expected.js
new file mode 100644
--- /dev/null
+++ b/test/js/samples/head-no-whitespace/expected.js
@@ -0,0 +1,50 @@
+/* generated by Svelte vX.Y.Z */
+import { appendNode, assign, createElement, detachNode, init, noop, proto } from "svelte/shared.js";
+
+function create_main_fragment(state, component) {
+	var meta, meta_1;
+
+	return {
+		c: function create() {
+			meta = createElement("meta");
+			meta_1 = createElement("meta");
+			this.h();
+		},
+
+		h: function hydrate() {
+			meta.name = "twitter:creator";
+			meta.content = "@sveltejs";
+			meta_1.name = "twitter:title";
+			meta_1.content = "Svelte";
+		},
+
+		m: function mount(target, anchor) {
+			appendNode(meta, document.head);
+			appendNode(meta_1, document.head);
+		},
+
+		p: noop,
+
+		u: function unmount() {
+			detachNode(meta);
+			detachNode(meta_1);
+		},
+
+		d: noop
+	};
+}
+
+function SvelteComponent(options) {
+	init(this, options);
+	this._state = assign({}, options.data);
+
+	this._fragment = create_main_fragment(this._state, this);
+
+	if (options.target) {
+		this._fragment.c();
+		this._fragment.m(options.target, options.anchor || null);
+	}
+}
+
+assign(SvelteComponent.prototype, proto);
+export default SvelteComponent;
\ No newline at end of file
diff --git a/test/js/samples/head-no-whitespace/input.html b/test/js/samples/head-no-whitespace/input.html
new file mode 100644
--- /dev/null
+++ b/test/js/samples/head-no-whitespace/input.html
@@ -0,0 +1,4 @@
+<:Head>
+	<meta name='twitter:creator' content='@sveltejs'>
+	<meta name='twitter:title' content='Svelte'>
+</:Head>
\ No newline at end of file