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/**
* @fileoverview Reject use of lazy getters for modules that's loaded early in
* the startup process and not necessarily be lazy.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
*/
"use strict";
const helpers = require("../helpers");
function isIdentifier(node, id) {
return node.type === "Identifier" && node.name === id;
}
function isString(node) {
return node.type === "Literal" && typeof node.value === "string";
}
function checkMixed(loadedModules, context, node, type, resourceURI) {
if (!loadedModules.has(resourceURI)) {
loadedModules.set(resourceURI, type);
}
if (loadedModules.get(resourceURI) === type) {
return;
}
context.report({
node,
messageId: "mixedEagerAndLazy",
data: { uri: resourceURI },
});
}
module.exports = {
meta: {
},
messages: {
mixedEagerAndLazy:
'Module "{{uri}}" is loaded eagerly, and should not be used for lazy getter.',
},
schema: [],
type: "problem",
},
create(context) {
const loadedModules = new Map();
return {
ImportDeclaration(node) {
const resourceURI = node.source.value;
checkMixed(loadedModules, context, node, "eager", resourceURI);
},
CallExpression(node) {
if (node.callee.type !== "MemberExpression") {
return;
}
let callerSource;
try {
callerSource = helpers.getASTSource(node.callee);
} catch (e) {
return;
}
if (
(callerSource === "ChromeUtils.import" ||
callerSource === "ChromeUtils.importESModule") &&
helpers.getIsTopLevelAndUnconditionallyExecuted(
helpers.getAncestors(context, node)
)
) {
if (node.arguments.length < 1) {
return;
}
const resourceURINode = node.arguments[0];
if (!isString(resourceURINode)) {
return;
}
checkMixed(
loadedModules,
context,
node,
"eager",
resourceURINode.value
);
}
if (callerSource === "ChromeUtils.defineModuleGetter") {
if (node.arguments.length < 3) {
return;
}
if (!isIdentifier(node.arguments[0], "lazy")) {
return;
}
const resourceURINode = node.arguments[2];
if (!isString(resourceURINode)) {
return;
}
checkMixed(
loadedModules,
context,
node,
"lazy",
resourceURINode.value
);
} else if (
callerSource === "XPCOMUtils.defineLazyModuleGetters" ||
callerSource === "ChromeUtils.defineESModuleGetters"
) {
if (node.arguments.length < 2) {
return;
}
if (!isIdentifier(node.arguments[0], "lazy")) {
return;
}
const obj = node.arguments[1];
if (obj.type !== "ObjectExpression") {
return;
}
for (let prop of obj.properties) {
if (prop.type !== "Property") {
continue;
}
if (prop.kind !== "init") {
continue;
}
const resourceURINode = prop.value;
if (!isString(resourceURINode)) {
continue;
}
checkMixed(
loadedModules,
context,
node,
"lazy",
resourceURINode.value
);
}
}
},
};
},
};