78 lines
2.0 KiB
JavaScript
78 lines
2.0 KiB
JavaScript
/**
|
|
* @fileoverview Rule to flag references to the undefined variable.
|
|
* @author Michael Ficarra
|
|
*/
|
|
"use strict";
|
|
|
|
//------------------------------------------------------------------------------
|
|
// Rule Definition
|
|
//------------------------------------------------------------------------------
|
|
|
|
module.exports = {
|
|
meta: {
|
|
docs: {
|
|
description: "disallow the use of `undefined` as an identifier",
|
|
category: "Variables",
|
|
recommended: false
|
|
},
|
|
|
|
schema: []
|
|
},
|
|
|
|
create(context) {
|
|
|
|
/**
|
|
* Report an invalid "undefined" identifier node.
|
|
* @param {ASTNode} node The node to report.
|
|
* @returns {void}
|
|
*/
|
|
function report(node) {
|
|
context.report({
|
|
node,
|
|
message: "Unexpected use of undefined."
|
|
});
|
|
}
|
|
|
|
/**
|
|
* Checks the given scope for references to `undefined` and reports
|
|
* all references found.
|
|
* @param {eslint-scope.Scope} scope The scope to check.
|
|
* @returns {void}
|
|
*/
|
|
function checkScope(scope) {
|
|
const undefinedVar = scope.set.get("undefined");
|
|
|
|
if (!undefinedVar) {
|
|
return;
|
|
}
|
|
|
|
const references = undefinedVar.references;
|
|
|
|
const defs = undefinedVar.defs;
|
|
|
|
// Report non-initializing references (those are covered in defs below)
|
|
references
|
|
.filter(ref => !ref.init)
|
|
.forEach(ref => report(ref.identifier));
|
|
|
|
defs.forEach(def => report(def.name));
|
|
}
|
|
|
|
return {
|
|
"Program:exit"() {
|
|
const globalScope = context.getScope();
|
|
|
|
const stack = [globalScope];
|
|
|
|
while (stack.length) {
|
|
const scope = stack.pop();
|
|
|
|
stack.push.apply(stack, scope.childScopes);
|
|
checkScope(scope);
|
|
}
|
|
}
|
|
};
|
|
|
|
}
|
|
};
|