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/**
* @fileoverview Simply marks exported symbols as used. Designed for use in
* .jsm files only.
*
* 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";
function markArrayElementsAsUsed(context, node, expression) {
if (expression.type != "ArrayExpression") {
context.report({
node,
messageId: "nonArrayAssignedToImported",
});
return;
}
for (let element of expression.elements) {
context.markVariableAsUsed
? context.markVariableAsUsed(element.value)
: context.sourceCode.markVariableAsUsed(element.value);
}
// Also mark EXPORTED_SYMBOLS as used.
context.markVariableAsUsed
? context.markVariableAsUsed("EXPORTED_SYMBOLS")
: context.sourceCode.markVariableAsUsed("EXPORTED_SYMBOLS");
}
// Ignore assignments not in the global scope, e.g. where special module
// definitions are required due to having different ways of importing files,
// e.g. osfile.
function isGlobalScope(context, node) {
if (context.sourceCode?.getScope) {
let upper = context.sourceCode.getScope(node).upper;
// ESLint v9 uses a global scope object with type = "global". Earlier
// versions use a null upper scope.
return !upper || upper.type == "global";
}
return !context.getScope().upper;
}
module.exports = {
meta: {
docs: {
},
messages: {
useLetForExported:
"EXPORTED_SYMBOLS cannot be declared via `let`. Use `var` or `this.EXPORTED_SYMBOLS =`",
nonArrayAssignedToImported:
"Unexpected assignment of non-Array to EXPORTED_SYMBOLS",
},
schema: [],
type: "problem",
},
create(context) {
return {
AssignmentExpression(node) {
if (
node.operator === "=" &&
node.left.type === "MemberExpression" &&
node.left.object.type === "ThisExpression" &&
node.left.property.name === "EXPORTED_SYMBOLS" &&
isGlobalScope(context, node)
) {
markArrayElementsAsUsed(context, node, node.right);
}
},
VariableDeclaration(node) {
if (!isGlobalScope(context, node)) {
return;
}
for (let item of node.declarations) {
if (
item.id &&
item.id.type == "Identifier" &&
item.id.name === "EXPORTED_SYMBOLS"
) {
if (node.kind === "let") {
// The use of 'let' isn't allowed as the lexical scope may die after
// the script executes.
context.report({
node,
messageId: "useLetForExported",
});
}
markArrayElementsAsUsed(context, node, item.init);
}
}
},
};
},
};