You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
svelte/src/generators/dom/index.ts

462 lines
13 KiB

import MagicString from 'magic-string';
import { parseExpressionAt } from 'acorn';
import annotateWithScopes from '../../utils/annotateWithScopes';
import isReference from '../../utils/isReference';
import { walk } from 'estree-walker';
import deindent from '../../utils/deindent';
import { stringify, escape } from '../../utils/stringify';
import CodeBuilder from '../../utils/CodeBuilder';
import globalWhitelist from '../../utils/globalWhitelist';
import reservedNames from '../../utils/reservedNames';
import shared from './shared';
import Generator from '../Generator';
import Stylesheet from '../../css/Stylesheet';
import Block from './Block';
import { test } from '../../config';
import { Parsed, CompileOptions, Node } from '../../interfaces';
export class DomGenerator extends Generator {
blocks: (Block|string)[];
readonly: Set<string>;
metaBindings: string[];
hydratable: boolean;
legacy: boolean;
hasIntroTransitions: boolean;
hasOutroTransitions: boolean;
hasComplexBindings: boolean;
needsEncapsulateHelper: boolean;
constructor(
parsed: Parsed,
source: string,
name: string,
stylesheet: Stylesheet,
options: CompileOptions
) {
super(parsed, source, name, stylesheet, options, true);
this.blocks = [];
this.readonly = new Set();
this.hydratable = options.hydratable;
this.legacy = options.legacy;
this.needsEncapsulateHelper = false;
// initial values for e.g. window.innerWidth, if there's a <:Window> meta tag
this.metaBindings = [];
}
getUniqueNameMaker(params: string[]) {
const localUsedNames = new Set(params);
function add(name: string) {
localUsedNames.add(name);
}
reservedNames.forEach(add);
this.userVars.forEach(add);
for (const name in shared) {
localUsedNames.add(test ? `${name}$` : name);
}
return (name: string) => {
if (test) name = `${name}$`;
let alias = name;
for (
let i = 1;
this.usedNames.has(alias) ||
localUsedNames.has(alias);
alias = `${name}_${i++}`
);
localUsedNames.add(alias);
return alias;
};
}
}
export default function dom(
parsed: Parsed,
source: string,
stylesheet: Stylesheet,
options: CompileOptions
) {
const format = options.format || 'es';
const generator = new DomGenerator(parsed, source, options.name || 'SvelteComponent', stylesheet, options);
const {
computations,
name,
templateProperties,
namespace,
} = generator;
parsed.html.build();
const { block } = parsed.html;
generator.stylesheet.warnOnUnusedSelectors(options.onwarn);
const builder = new CodeBuilder();
const computationBuilder = new CodeBuilder();
const computationDeps = new Set();
if (computations.length) {
computations.forEach(({ key, deps }) => {
deps.forEach(dep => {
computationDeps.add(dep);
});
if (generator.readonly.has(key)) {
// <:Window> bindings
throw new Error(
`Cannot have a computed value '${key}' that clashes with a read-only property`
);
}
generator.readonly.add(key);
const condition = `${deps.map(dep => `changed.${dep}`).join(' || ')}`;
const statement = `if (@differs(state.${key}, (state.${key} = %computed-${key}(${deps
.map(dep => `state.${dep}`)
.join(', ')})))) changed.${key} = true;`;
computationBuilder.addConditional(condition, statement);
});
}
if (generator.javascript) {
builder.addBlock(generator.javascript);
}
if (generator.needsEncapsulateHelper) {
builder.addBlock(deindent`
function @encapsulateStyles(node) {
@setAttribute(node, "${generator.stylesheet.id}", "");
}
`);
}
const { css, cssMap } = generator.stylesheet.render(options.filename, !generator.customElement);
const styles = generator.stylesheet.hasStyles && stringify(options.dev ?
`${css}\n/*# sourceMappingURL=${cssMap.toUrl()} */` :
css, { onlyEscapeAtSymbol: true });
if (styles && generator.options.css !== false && !generator.customElement) {
builder.addBlock(deindent`
function @add_css() {
var style = @createElement("style");
style.id = '${generator.stylesheet.id}-style';
style.textContent = ${styles};
@appendNode(style, document.head);
}
`);
}
generator.blocks.forEach(block => {
builder.addBlock(block.toString());
});
const sharedPath: string = options.shared === true
? 'svelte/shared.js'
: options.shared || '';
const prototypeBase =
`${name}.prototype` +
(templateProperties.methods ? `, %methods` : '');
const proto = sharedPath
? `@proto`
: deindent`
{
${['destroy', 'get', 'fire', 'observe', 'on', 'set', 'teardown', '_set', '_mount', '_unmount']
.map(n => `${n}: @${n === 'teardown' ? 'destroy' : n}`)
.join(',\n')}
}`;
const debugName = `<${generator.customElement ? generator.tag : name}>`;
// generate initial state object
const expectedProperties = Array.from(generator.expectedProperties);
const globals = expectedProperties.filter(prop => globalWhitelist.has(prop));
const storeProps = options.store ? expectedProperties.filter(prop => prop[0] === '$') : [];
const initialState = [];
if (globals.length > 0) {
initialState.push(`{ ${globals.map(prop => `${prop} : ${prop}`).join(', ')} }`);
}
if (storeProps.length > 0) {
initialState.push(`this.store._init([${storeProps.map(prop => `"${prop.slice(1)}"`)}])`);
}
if (templateProperties.data) {
initialState.push(`%data()`);
} else if (globals.length === 0 && storeProps.length === 0) {
initialState.push('{}');
}
initialState.push(`options.data`);
const constructorBody = deindent`
${options.dev && `this._debugName = '${debugName}';`}
${options.dev && !generator.customElement &&
`if (!options || (!options.target && !options._root)) throw new Error("'target' is a required option");`}
@init(this, options);
${generator.usesRefs && `this.refs = {};`}
this._state = @assign(${initialState.join(', ')});
${storeProps.length > 0 && `this.store._add(this, [${storeProps.map(prop => `"${prop.slice(1)}"`)}]);`}
${generator.metaBindings}
${computations.length && `this._recompute({ ${Array.from(computationDeps).map(dep => `${dep}: 1`).join(', ')} }, this._state);`}
${options.dev &&
Array.from(generator.expectedProperties).map(
prop =>
`if (!('${prop}' in this._state)) console.warn("${debugName} was created without expected data property '${prop}'");`
)}
${generator.bindingGroups.length &&
`this._bindingGroups = [${Array(generator.bindingGroups.length).fill('[]').join(', ')}];`}
${(templateProperties.ondestroy || storeProps.length) && (
`this._handlers.destroy = [${
[templateProperties.ondestroy && `%ondestroy`, storeProps.length && `@removeFromStore`].filter(Boolean).join(', ')
}];`
)}
${generator.slots.size && `this._slotted = options.slots || {};`}
${generator.customElement ?
deindent`
this.attachShadow({ mode: 'open' });
${css && `this.shadowRoot.innerHTML = \`<style>${escape(css, { onlyEscapeAtSymbol: true }).replace(/\\/g, '\\\\')}${options.dev ? `\n/*# sourceMappingURL=${cssMap.toUrl()} */` : ''}</style>\`;`}
` :
(generator.stylesheet.hasStyles && options.css !== false &&
`if (!document.getElementById("${generator.stylesheet.id}-style")) @add_css();`)
}
${templateProperties.oncreate && `var _oncreate = %oncreate.bind(this);`}
${(templateProperties.oncreate || generator.hasComponents || generator.hasComplexBindings || generator.hasIntroTransitions) && deindent`
if (!options._root) {
this._oncreate = [${templateProperties.oncreate && `_oncreate`}];
${(generator.hasComponents || generator.hasComplexBindings) && `this._beforecreate = [];`}
${(generator.hasComponents || generator.hasIntroTransitions) && `this._aftercreate = [];`}
} ${templateProperties.oncreate && deindent`
else {
this._root._oncreate.push(_oncreate);
}
`}
`}
${generator.slots.size && `this.slots = {};`}
this._fragment = @create_main_fragment(this._state, this);
${generator.customElement ? deindent`
this._fragment.c();
this._fragment.${block.hasIntroMethod ? 'i' : 'm'}(this.shadowRoot, null);
if (options.target) this._mount(options.target, options.anchor || null);
` : deindent`
if (options.target) {
${generator.hydratable
? deindent`
var nodes = @children(options.target);
options.hydrate ? this._fragment.l(nodes) : this._fragment.c();
nodes.forEach(@detachNode);
` :
deindent`
${options.dev && `if (options.hydrate) throw new Error("options.hydrate only works if the component was compiled with the \`hydratable: true\` option");`}
this._fragment.c();
`}
this._fragment.${block.hasIntroMethod ? 'i' : 'm'}(options.target, options.anchor || null);
${(generator.hasComponents || generator.hasComplexBindings || templateProperties.oncreate || generator.hasIntroTransitions) && deindent`
${generator.hasComponents && `this._lock = true;`}
${(generator.hasComponents || generator.hasComplexBindings) && `@callAll(this._beforecreate);`}
${(generator.hasComponents || templateProperties.oncreate) && `@callAll(this._oncreate);`}
${(generator.hasComponents || generator.hasIntroTransitions) && `@callAll(this._aftercreate);`}
${generator.hasComponents && `this._lock = false;`}
`}
}
`}
`;
if (generator.customElement) {
const props = generator.props || Array.from(generator.expectedProperties);
builder.addBlock(deindent`
class ${name} extends HTMLElement {
constructor(options = {}) {
super();
${constructorBody}
}
static get observedAttributes() {
return ${JSON.stringify(props)};
}
${props.map(prop => deindent`
get ${prop}() {
return this.get('${prop}');
}
set ${prop}(value) {
this.set({ ${prop}: value });
}
`).join('\n\n')}
${generator.slots.size && deindent`
connectedCallback() {
Object.keys(this._slotted).forEach(key => {
this.appendChild(this._slotted[key]);
});
}`}
attributeChangedCallback(attr, oldValue, newValue) {
this.set({ [attr]: newValue });
}
}
customElements.define("${generator.tag}", ${name});
@assign(${prototypeBase}, ${proto}, {
_mount(target, anchor) {
target.insertBefore(this, anchor);
},
_unmount() {
this.parentNode.removeChild(this);
}
});
`);
} else {
builder.addBlock(deindent`
function ${name}(options) {
${constructorBody}
}
@assign(${prototypeBase}, ${proto});
`);
}
builder.addBlock(deindent`
${options.dev && deindent`
${name}.prototype._checkReadOnly = function _checkReadOnly(newState) {
${Array.from(generator.readonly).map(
prop =>
`if ('${prop}' in newState && !this._updatingReadonlyProperty) throw new Error("${debugName}: Cannot set read-only property '${prop}'");`
)}
};
`}
${computations.length ? deindent`
${name}.prototype._recompute = function _recompute(changed, state) {
${computationBuilder}
}
` : (!sharedPath && `${name}.prototype._recompute = @noop;`)}
${templateProperties.setup && `%setup(${name});`}
${templateProperties.preload && `${name}.preload = %preload;`}
`);
const usedHelpers = new Set();
let result = builder
.toString()
.replace(/(%+|@+)(\w*(?:-\w*)?)/g, (match: string, sigil: string, name: string) => {
if (sigil === '@') {
if (name in shared) {
if (options.dev && `${name}Dev` in shared) name = `${name}Dev`;
usedHelpers.add(name);
}
return generator.alias(name);
}
if (sigil === '%') {
return generator.templateVars.get(name);
}
return sigil.slice(1) + name;
});
let helpers;
if (sharedPath) {
if (format !== 'es' && format !== 'cjs') {
throw new Error(`Components with shared helpers must be compiled with \`format: 'es'\` or \`format: 'cjs'\``);
}
const used = Array.from(usedHelpers).sort();
helpers = used.map(name => {
const alias = generator.alias(name);
return { name, alias };
});
} else {
let inlineHelpers = '';
usedHelpers.forEach(key => {
const str = shared[key];
const code = new MagicString(str);
const expression = parseExpressionAt(str, 0);
let scope = annotateWithScopes(expression);
walk(expression, {
enter(node: Node, parent: Node) {
if (node._scope) scope = node._scope;
if (
node.type === 'Identifier' &&
isReference(node, parent) &&
!scope.has(node.name)
) {
if (node.name in shared) {
// this helper function depends on another one
const dependency = node.name;
usedHelpers.add(dependency);
const alias = generator.alias(dependency);
if (alias !== node.name)
code.overwrite(node.start, node.end, alias);
}
}
},
leave(node: Node) {
if (node._scope) scope = scope.parent;
},
});
if (key === 'transitionManager') {
// special case
const global = `_svelteTransitionManager`;
inlineHelpers += `\n\nvar ${generator.alias('transitionManager')} = window.${global} || (window.${global} = ${code});\n\n`;
} else {
const alias = generator.alias(expression.id.name);
if (alias !== expression.id.name)
code.overwrite(expression.id.start, expression.id.end, alias);
inlineHelpers += `\n\n${code}`;
}
});
result += inlineHelpers;
}
const filename = options.filename && (
typeof process !== 'undefined' ? options.filename.replace(process.cwd(), '').replace(/^[\/\\]/, '') : options.filename
);
return generator.generate(result, options, {
banner: `/* ${filename ? `${filename} ` : ``}generated by Svelte v${"__VERSION__"} */`,
sharedPath,
helpers,
name,
format,
});
}