File: /var/www/quadcode.com/node_modules/svelte/src/compiler/compile/nodes/shared/Expression.js
import { walk } from 'estree-walker';
import is_reference from 'is-reference';
import flatten_reference from '../../utils/flatten_reference.js';
import { create_scopes, extract_names } from '../../utils/scope.js';
import { sanitize } from '../../../utils/names.js';
import get_object from '../../utils/get_object.js';
import is_dynamic from '../../render_dom/wrappers/shared/is_dynamic.js';
import { b } from 'code-red';
import { invalidate } from '../../render_dom/invalidate.js';
import { is_reserved_keyword } from '../../utils/reserved_keywords.js';
import replace_object from '../../utils/replace_object.js';
import is_contextual from './is_contextual.js';
import { clone } from '../../../utils/clone.js';
import compiler_errors from '../../compiler_errors.js';
const regex_contains_term_function_expression = /FunctionExpression/;
export default class Expression {
/** @type {'Expression'} */
type = 'Expression';
/** @type {import('../../Component.js').default} */
component;
/** @type {import('../interfaces.js').INode} */
owner;
/** @type {import('estree').Node} */
node;
/** @type {Set<string>} */
references = new Set();
/**
* Dependencies declared in the script block
* @type {Set<string>}
*/
dependencies = new Set();
/**
* Dependencies declared in the HTML-like template section
* @type {Set<string>}
*/
contextual_dependencies = new Set();
/** @type {import('./TemplateScope.js').default} */
template_scope;
/** @type {import('../../utils/scope.js').Scope} */
scope;
/** @type {WeakMap<import('estree').Node, import('../../utils/scope.js').Scope>} */
scope_map;
/** @type {Array<import('estree').Node | import('estree').Node[]>} */
declarations = [];
/** @type {boolean} */
uses_context = false;
/** @type {import('estree').Node} */
manipulated;
/**
* @param {import('../../Component.js').default} component *
* @param {import('../interfaces.js').INode} owner *
* @param {import('./TemplateScope.js').default} template_scope *
* @param {import('estree').Node} info *
* @param {boolean} [lazy] undefined
*/
constructor(component, owner, template_scope, info, lazy) {
// TODO revert to direct property access in prod?
Object.defineProperties(this, {
component: {
value: component
}
});
this.node = info;
this.template_scope = template_scope;
this.owner = owner;
const { dependencies, contextual_dependencies, references } = this;
let { map, scope } = create_scopes(info);
this.scope = scope;
this.scope_map = map;
const expression = this;
let function_expression;
// discover dependencies, but don't change the code yet
walk(info, {
/**
* @param {any} node
* @param {import('estree').Node} parent
* @param {string} key
*/
enter(node, parent, key) {
// don't manipulate shorthand props twice
if (key === 'key' && /** @type {import('estree').Property} */ (parent).shorthand) return;
// don't manipulate `import.meta`, `new.target`
if (node.type === 'MetaProperty') return this.skip();
if (map.has(node)) {
scope = map.get(node);
}
if (!function_expression && regex_contains_term_function_expression.test(node.type)) {
function_expression = node;
}
if (is_reference(node, parent)) {
const { name, nodes } = flatten_reference(node);
references.add(name);
if (scope.has(name)) return;
if (name[0] === '$') {
const store_name = name.slice(1);
if (template_scope.names.has(store_name) || scope.has(store_name)) {
return component.error(node, compiler_errors.contextual_store);
}
}
if (template_scope.is_let(name)) {
if (!lazy) {
contextual_dependencies.add(name);
dependencies.add(name);
}
} else if (template_scope.names.has(name)) {
expression.uses_context = true;
contextual_dependencies.add(name);
const owner = template_scope.get_owner(name);
const is_index = owner.type === 'EachBlock' && owner.key && name === owner.index;
if (!lazy || is_index) {
template_scope.dependencies_for_name
.get(name)
.forEach((name) => dependencies.add(name));
}
} else {
if (!lazy) {
const variable = component.var_lookup.get(name);
if (!variable || !variable.imported || variable.mutated || variable.reassigned) {
dependencies.add(name);
}
}
component.add_reference(node, name);
component.warn_if_undefined(name, nodes[0], template_scope, owner);
}
this.skip();
}
// track any assignments from template expressions as mutable
let names;
let deep = false;
if (function_expression) {
if (node.type === 'AssignmentExpression') {
deep = node.left.type === 'MemberExpression';
names = extract_names(deep ? get_object(node.left) : node.left);
} else if (node.type === 'UpdateExpression') {
deep = node.argument.type === 'MemberExpression';
names = extract_names(get_object(node.argument));
}
}
if (names) {
names.forEach((name) => {
if (template_scope.names.has(name)) {
if (template_scope.is_const(name)) {
component.error(node, compiler_errors.invalid_const_update(name));
}
template_scope.dependencies_for_name.get(name).forEach((name) => {
const variable = component.var_lookup.get(name);
if (variable) variable[deep ? 'mutated' : 'reassigned'] = true;
});
const each_block = template_scope.get_owner(name);
/** @type {import('../EachBlock.js').default} */ (each_block).has_binding = true;
} else {
component.add_reference(node, name);
const variable = component.var_lookup.get(name);
if (variable) {
variable[deep ? 'mutated' : 'reassigned'] = true;
}
const declaration = scope.find_owner(name)?.declarations.get(name);
if (declaration) {
if (
/** @type {import('estree').VariableDeclaration} */ (declaration).kind ===
'const' &&
!deep
) {
component.error(node, {
code: 'assignment-to-const',
message: 'You are assigning to a const'
});
}
} else if (variable && variable.writable === false && !deep) {
component.error(node, {
code: 'assignment-to-const',
message: 'You are assigning to a const'
});
}
}
});
}
},
/** @type {import('estree-walker').SyncHandler} */
leave(node) {
if (map.has(node)) {
scope = scope.parent;
}
if (node === function_expression) {
function_expression = null;
}
}
});
}
dynamic_dependencies() {
return Array.from(this.dependencies).filter((name) => {
if (this.template_scope.is_let(name)) return true;
if (is_reserved_keyword(name)) return true;
const variable = this.component.var_lookup.get(name);
return is_dynamic(variable);
});
}
dynamic_contextual_dependencies() {
return Array.from(this.contextual_dependencies).filter((name) => {
return Array.from(this.template_scope.dependencies_for_name.get(name)).some(
(variable_name) => {
const variable = this.component.var_lookup.get(variable_name);
return is_dynamic(variable);
}
);
});
}
// TODO move this into a render-dom wrapper?
/**
* @param {import('../../render_dom/Block.js').default} [block]
* @param {string | void} [ctx]
*/
manipulate(block, ctx) {
// TODO ideally we wouldn't end up calling this method
// multiple times
if (this.manipulated) return this.manipulated;
const { component, declarations, scope_map: map, template_scope, owner } = this;
let scope = this.scope;
/** @type {import('estree').FunctionExpression | import('estree').ArrowFunctionExpression | null} */
let function_expression;
/** @type {Set<string>} */
let dependencies;
/** @type {Set<string>} */
let contextual_dependencies;
const node = walk(this.node, {
/** @type {import('estree-walker').SyncHandler} */
enter(node, parent) {
if (node.type === 'Property' && node.shorthand) {
node.value = clone(node.value);
node.shorthand = false;
}
if (map.has(node)) {
scope = map.get(node);
}
if (node.type === 'Identifier' && is_reference(node, parent)) {
const { name } = flatten_reference(node);
if (scope.has(name)) return;
if (function_expression) {
if (template_scope.names.has(name)) {
contextual_dependencies.add(name);
template_scope.dependencies_for_name.get(name).forEach((dependency) => {
dependencies.add(dependency);
});
} else {
dependencies.add(name);
component.add_reference(node, name); // TODO is this redundant/misplaced?
}
} else if (is_contextual(component, template_scope, name)) {
const reference = block.renderer.reference(node, ctx);
this.replace(reference);
}
this.skip();
}
if (!function_expression) {
if (node.type === 'AssignmentExpression') {
// TODO should this be a warning/error? `<p>{foo = 1}</p>`
}
if (node.type === 'FunctionExpression' || node.type === 'ArrowFunctionExpression') {
function_expression = node;
dependencies = new Set();
contextual_dependencies = new Set();
}
}
},
/** @type {import('estree-walker').SyncHandler} */
leave(node, parent) {
if (map.has(node)) scope = scope.parent;
if (node === function_expression) {
const id = component.get_unique_name(sanitize(get_function_name(node, owner)));
const declaration = b`const ${id} = ${node}`;
const extract_functions = () => {
const deps = Array.from(contextual_dependencies);
const function_expression = /** @type {import('estree').FunctionExpression} */ (node);
const has_args = function_expression.params.length > 0;
function_expression.params = [
...deps.map(
(name) => /** @type {import('estree').Identifier} */ ({ type: 'Identifier', name })
),
...function_expression.params
];
const context_args = deps.map((name) => block.renderer.reference(name, ctx));
component.partly_hoisted.push(declaration);
block.renderer.add_to_context(id.name);
const callee = block.renderer.reference(id);
this.replace(id);
const func_declaration = has_args
? b`function ${id}(...args) {
return ${callee}(${context_args}, ...args);
}`
: b`function ${id}() {
return ${callee}(${context_args});
}`;
return { deps, func_declaration };
};
if (owner.type === 'ConstTag') {
// we need a combo block/init recipe
if (contextual_dependencies.size === 0) {
let child_scope = scope;
walk(node, {
/** @type {import('estree-walker').SyncHandler} */
enter(node, parent) {
if (map.has(node)) child_scope = map.get(node);
if (node.type === 'Identifier' && is_reference(node, parent)) {
if (child_scope.has(node.name)) return;
this.replace(block.renderer.reference(node, ctx));
}
},
/** @param {import('estree').Node} node */
leave(node) {
if (map.has(node)) child_scope = child_scope.parent;
}
});
} else {
const { func_declaration } = extract_functions();
this.replace(func_declaration[0]);
}
} else if (dependencies.size === 0 && contextual_dependencies.size === 0) {
// we can hoist this out of the component completely
component.fully_hoisted.push(declaration);
this.replace(id);
component.add_var(node, {
name: id.name,
internal: true,
hoistable: true,
referenced: true
});
} else if (contextual_dependencies.size === 0) {
// function can be hoisted inside the component init
component.partly_hoisted.push(declaration);
block.renderer.add_to_context(id.name);
this.replace(block.renderer.reference(id));
} else {
// we need a combo block/init recipe
const { deps, func_declaration } = extract_functions();
if (owner.type === 'Attribute' && owner.parent.name === 'slot') {
/** @type {Set<import('../interfaces.js').INode>} */
const dep_scopes = new Set(deps.map((name) => template_scope.get_owner(name)));
// find the nearest scopes
/** @type {import('../interfaces.js').INode} */
let node = owner.parent;
while (node && !dep_scopes.has(node)) {
node = node.parent;
}
const func_expression = func_declaration[0];
if (node.type === 'SlotTemplate') {
// <svelte:fragment let:data />
this.replace(func_expression);
} else {
// {#each}, {#await}
const func_id = component.get_unique_name(id.name + '_func');
block.renderer.add_to_context(func_id.name, true);
// rename #ctx -> child_ctx;
walk(func_expression, {
/** @param {import('estree').Node} node */
enter(node) {
if (node.type === 'Identifier' && node.name === '#ctx') {
node.name = 'child_ctx';
}
}
});
// add to get_xxx_context
// child_ctx[x] = function () { ... }
/** @type {import('../EachBlock.js').default} */ (
template_scope.get_owner(deps[0])
).contexts.push({
type: 'DestructuredVariable',
key: func_id,
modifier: () => func_expression,
default_modifier: (node) => node
});
this.replace(block.renderer.reference(func_id));
}
} else {
declarations.push(func_declaration);
}
}
function_expression = null;
dependencies = null;
contextual_dependencies = null;
if (parent && parent.type === 'Property') {
parent.method = false;
}
}
if (node.type === 'AssignmentExpression' || node.type === 'UpdateExpression') {
const assignee = node.type === 'AssignmentExpression' ? node.left : node.argument;
const object_name = get_object(assignee).name;
if (scope.has(object_name)) return;
// normally (`a = 1`, `b.c = 2`), there'll be a single name
// (a or b). In destructuring cases (`[d, e] = [e, d]`) there
// may be more, in which case we need to tack the extra ones
// onto the initial function call
const names = new Set(extract_names(/** @type {import('estree').Node} */ (assignee)));
/** @type {Set<string>} */
const traced = new Set();
names.forEach((name) => {
const dependencies = template_scope.dependencies_for_name.get(name);
if (dependencies) {
dependencies.forEach((name) => traced.add(name));
} else {
traced.add(name);
}
});
const context = block.bindings.get(object_name);
if (context) {
// for `{#each array as item}`
// replace `item = 1` to `each_array[each_index] = 1`, this allow us to mutate the array
// rather than mutating the local `item` variable
const { snippet, object, property } = context;
/** @type {any} */
const replaced = replace_object(assignee, snippet);
if (node.type === 'AssignmentExpression') {
node.left = replaced;
} else {
node.argument = replaced;
}
contextual_dependencies.add(object.name);
contextual_dependencies.add(property.name);
}
this.replace(invalidate(block.renderer, scope, node, traced));
}
}
});
if (declarations.length > 0) {
block.maintain_context = true;
declarations.forEach((declaration) => {
block.chunks.init.push(declaration);
});
}
return (this.manipulated = /** @type {import('estree').Node} */ (node));
}
}
/**
* @param {import('estree').Node} _node
* @param {import('../interfaces.js').INode} parent
*/
function get_function_name(_node, parent) {
if (parent.type === 'EventHandler') {
return `${parent.name}_handler`;
}
if (parent.type === 'Action') {
return `${parent.name}_function`;
}
return 'func';
}