eslint-plugin-regexp
Version:
ESLint plugin for finding RegExp mistakes and RegExp style guide violations.
82 lines (81 loc) • 2.89 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
const regexp_ast_analysis_1 = require("regexp-ast-analysis");
const utils_1 = require("../utils");
function isZeroQuantifier(node) {
return node.min === 0;
}
function isOptional(assertion, quantifier, flags) {
let element = assertion;
while (element.parent !== quantifier) {
const parent = element.parent;
if (parent.type === "Alternative") {
for (const e of parent.elements) {
if (e === element) {
continue;
}
if (!(0, regexp_ast_analysis_1.isZeroLength)(e, flags)) {
return false;
}
}
if (parent.parent.type === "Pattern") {
throw new Error("The given assertion is not a descendant of the given quantifier.");
}
element = parent.parent;
}
else {
if (parent.max > 1 && !(0, regexp_ast_analysis_1.isZeroLength)(parent, flags)) {
return false;
}
element = parent;
}
}
return true;
}
exports.default = (0, utils_1.createRule)("no-optional-assertion", {
meta: {
docs: {
description: "disallow optional assertions",
category: "Possible Errors",
recommended: true,
},
schema: [],
messages: {
optionalAssertion: "This assertion effectively optional and does not change the pattern. Either remove the assertion or change the parent quantifier '{{quantifier}}'.",
},
type: "problem",
},
create(context) {
function createVisitor({ node, flags, getRegexpLocation, }) {
const zeroQuantifierStack = [];
return {
onQuantifierEnter(q) {
if (isZeroQuantifier(q)) {
zeroQuantifierStack.unshift(q);
}
},
onQuantifierLeave(q) {
if (zeroQuantifierStack[0] === q) {
zeroQuantifierStack.shift();
}
},
onAssertionEnter(assertion) {
const q = zeroQuantifierStack[0];
if (q && isOptional(assertion, q, flags)) {
context.report({
node,
loc: getRegexpLocation(assertion),
messageId: "optionalAssertion",
data: {
quantifier: q.raw.substr(q.element.raw.length),
},
});
}
},
};
}
return (0, utils_1.defineRegexpVisitor)(context, {
createVisitor,
});
},
});