[WIP] Dev helpers

src/generators/Generator.js

@@ -9,12 +9,13 @@ import getOutro from './shared/utils/getOutro.js';
 import annotateWithScopes from './annotateWithScopes.js';
 
 export default class Generator {
-	constructor ( parsed, source, name, names, visitors ) {
+	constructor ( parsed, source, name, names, visitors, options ) {
 		this.parsed = parsed;
 		this.source = source;
 		this.name = name;
 		this.names = names;
 		this.visitors = visitors;
+		this.options = options;
 
 		this.imports = [];
 		this.helpers = {};

src/generators/dom/index.js

@@ -8,8 +8,8 @@ import Generator from '../Generator.js';
 import * as shared from '../../shared/index.js';
 
 class DomGenerator extends Generator {
-	constructor ( parsed, source, name, names, visitors ) {
-		super( parsed, source, name, names, visitors );
+	constructor ( parsed, source, name, names, visitors, options ) {
+		super( parsed, source, name, names, visitors, options );
 		this.renderers = [];
 		this.uses = {};
 
@@ -132,6 +132,10 @@ class DomGenerator extends Generator {
 	}
 
 	helper ( name ) {
+		if ( this.options.dev && `${name}Dev` in shared ) {
+			name = `${name}Dev`;
+		}
+
 		this.uses[ name ] = true;
 
 		if ( !( name in this.aliases ) ) {
@@ -152,7 +156,7 @@ export default function dom ( parsed, source, options, names ) {
 	const format = options.format || 'es';
 	const name = options.name || 'SvelteComponent';
 
-	const generator = new DomGenerator( parsed, source, name, names, visitors );
+	const generator = new DomGenerator( parsed, source, name, names, visitors, options );
 
 	const { computations, templateProperties } = generator.parseJs();
 
@@ -359,34 +363,20 @@ export default function dom ( parsed, source, options, names ) {
 		}
 	` );
 
-	if ( templateProperties.methods ) {
-		builders.main.addBlock( `${name}.prototype = template.methods;` );
-	}
-
 	const sharedPath = options.shared === true ? 'svelte/shared.js' : options.shared;
 
-	builders.main.addBlock( sharedPath ?
-		deindent`
-			${name}.prototype.get = ${generator.helper( 'get' )};
-			${name}.prototype.fire = ${generator.helper( 'fire' )};
-			${name}.prototype.observe = ${generator.helper( 'observe' )};
-			${name}.prototype.on = ${generator.helper( 'on' )};
-			${name}.prototype.set = ${generator.helper( 'set' )};
-			${name}.prototype._flush = ${generator.helper( '_flush' )};
-		` :
-		deindent`
-			${name}.prototype.get = ${shared.get};
-
-			${name}.prototype.fire = ${shared.fire};
-
-			${name}.prototype.observe = ${shared.observe};
-
-			${name}.prototype.on = ${shared.on};
-
-			${name}.prototype.set = ${shared.set};
+	if ( sharedPath ) {
+		const base = templateProperties.methods ? `{}, template.methods` : `{}`;
+		builders.main.addBlock( `${name}.prototype = Object.assign( ${base}, ${generator.helper( 'proto' )} );` );
+	} else {
+		if ( templateProperties.methods ) {
+			builders.main.addBlock( `${name}.prototype = template.methods;` );
+		}
 
-			${name}.prototype._flush = ${shared._flush};
-		` );
+		[ 'get', 'fire', 'observe', 'on', 'set', '_flush' ].forEach( methodName => {
+			builders.main.addLine( `${name}.prototype.${methodName} = ${generator.helper( methodName )};` );
+		});
+	}
 
 	// TODO deprecate component.teardown()
 	builders.main.addBlock( deindent`
@@ -395,7 +385,7 @@ export default function dom ( parsed, source, options, names ) {
 		};
 
 		${name}.prototype.teardown = ${name}.prototype.destroy = function destroy ( detach ) {
-			this.fire( 'teardown' );${templateProperties.ondestroy ? `\ntemplate.ondestroy.call( this );` : ``}
+			this.fire( 'destroy' );${templateProperties.ondestroy ? `\ntemplate.ondestroy.call( this );` : ``}
 
 			this._fragment.teardown( detach !== false );
 			this._fragment = null;
@@ -420,13 +410,9 @@ export default function dom ( parsed, source, options, names ) {
 	} else {
 		Object.keys( generator.uses ).forEach( key => {
 			const fn = shared[ key ]; // eslint-disable-line import/namespace
-			if ( key !== generator.aliases[ key ] ) {
-				builders.main.addBlock( `var ${generator.aliases[ key ]} = ${fn.toString()}}` );
-			} else {
-				builders.main.addBlock( fn.toString() );
-			}
+			builders.main.addBlock( fn.toString().replace( /^function [^(]*/, 'function ' + generator.aliases[ key ] ) );
 		});
 	}
 
 	return generator.generate( builders.main.toString(), options, { name, format } );
-}
+}

src/generators/server-side-rendering/index.js

@@ -5,8 +5,8 @@ import visitors from './visitors/index.js';
 import Generator from '../Generator.js';
 
 class SsrGenerator extends Generator {
-	constructor ( parsed, source, name, names, visitors ) {
-		super( parsed, source, name, names, visitors );
+	constructor ( parsed, source, name, names, visitors, options ) {
+		super( parsed, source, name, names, visitors, options );
 		this.bindings = [];
 		this.renderCode = '';
 	}
@@ -36,7 +36,7 @@ export default function ssr ( parsed, source, options, names ) {
 	const format = options.format || 'cjs';
 	const name = options.name || 'SvelteComponent';
 
-	const generator = new SsrGenerator( parsed, source, name, names, visitors );
+	const generator = new SsrGenerator( parsed, source, name, names, visitors, options );
 
 	const { computations, templateProperties } = generator.parseJs();
 

src/shared/methods.js

@@ -30,7 +30,53 @@ export function observe ( key, callback, options ) {
 	};
 }
 
+export function observeDev ( key, callback, options ) {
+	var c = ( key = '' + key ).search( /[^\w]/ );
+	if ( c > -1 ) {
+		var message = "The first argument to component.observe(...) must be the name of a top-level property";
+		if ( c > 0 ) message += ", i.e. '" + key.slice( 0, c ) + "' rather than '" + key + "'";
+
+		throw new Error( message );
+	}
+
+	var group = ( options && options.defer ) ? this._observers.pre : this._observers.post;
+
+	( 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 );
+		}
+	};
+}
+
 export 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 );
+		}
+	};
+}
+
+export function onDev ( eventName, handler ) {
+	if ( eventName === 'teardown' ) {
+		console.warn( "Use component.on('destroy', ...) instead of component.on('teardown', ...) which has been deprecated and will be unsupported in Svelte 2" );
+		return this.on( 'destroy', handler );
+	}
+
 	var handlers = this._handlers[ eventName ] || ( this._handlers[ eventName ] = [] );
 	handlers.push( handler );
 
@@ -55,3 +101,21 @@ export function _flush () {
 		hook.fn.call( hook.context );
 	}
 }
+
+export var proto = {
+	get: get,
+	fire: fire,
+	observe: observe,
+	on: on,
+	set: set,
+	_flush: _flush
+};
+
+export var protoDev = {
+	get: get,
+	fire: fire,
+	observe: observeDev,
+	on: onDev,
+	set: set,
+	_flush: _flush
+};

test/generator/index.js

@@ -98,16 +98,31 @@ describe( 'generate', () => {
 
 					const target = window.document.querySelector( 'main' );
 
+					const warnings = [];
+					const warn = console.warn;
+					console.warn = warning => {
+						warnings.push( warning );
+					};
+
 					const component = new SvelteComponent({
 						target,
 						data: config.data
 					});
 
+					console.warn = warn;
+
 					if ( config.error ) {
 						unintendedError = true;
 						throw new Error( 'Expected a runtime error' );
 					}
 
+					if ( config.warnings ) {
+						assert.deepEqual( warnings, config.warnings );
+					} else if ( warnings.length ) {
+						unintendedError = true;
+						throw new Error( 'Received unexpected warnings' );
+					}
+
 					if ( config.html ) {
 						assert.htmlEqual( target.innerHTML, config.html );
 					}

test/generator/samples/dev-warning-bad-observe-arguments/_config.js

@@ -0,0 +1,7 @@
+export default {
+	dev: true,
+
+	error ( assert, err ) {
+		assert.equal( err.message, `The first argument to component.observe(...) must be the name of a top-level property, i.e. 'nested' rather than 'nested.data'` );
+	}
+};

test/generator/samples/dev-warning-bad-observe-arguments/main.html

@@ -0,0 +1,9 @@
+<script>
+	export default {
+		oncreate () {
+			this.observe( 'nested.data', data => {
+				console.log( 'nope' );
+			});
+		}
+	};
+</script>

test/generator/samples/dev-warning-destroy-not-teardown/_config.js

@@ -0,0 +1,7 @@
+export default {
+	dev: true,
+
+	warnings: [
+		`Use component.on('destroy', ...) instead of component.on('teardown', ...) which has been deprecated and will be unsupported in Svelte 2`
+	]
+};

test/generator/samples/dev-warning-destroy-not-teardown/main.html

@@ -0,0 +1,9 @@
+<script>
+	export default {
+		oncreate () {
+			this.on( 'teardown', () => {
+				this.destroyed = true;
+			});
+		}
+	};
+</script>

test/generator/samples/events-lifecycle/_config.js

@@ -2,7 +2,7 @@ export default {
 	test ( assert, component ) {
 		let count = 0;
 
-		component.on( 'teardown', function () {
+		component.on( 'destroy', function () {
 			assert.equal( this, component );
 			count += 1;
 		});