Bug: [prefer-regexp-exec] Runtime errors on malformed regular expressions #6928
Description
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- I have tried restarting my IDE and the issue persists.
- I have updated to the latest version of the packages.
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Issue Description
Hello friends,
The rule prefer-regexp-exec raises a runtime error in case the argument of String#match denotes a malformed regular expression.
For instance, linting
'foo'.match('[malformed');gives
Oops! Something went wrong! :(
ESLint: 8.38.0
SyntaxError: Invalid regular expression: /[malformed/: Unterminated character class
Occurred while linting /tmp/buggy-prefer-regexp-exec/file.ts:1
Rule: "@typescript-eslint/prefer-regexp-exec"
at RegExp (<anonymous>)
at CallExpression[arguments.length=1] > MemberExpression.callee[property.name='match'][computed=false] (/tmp/buggy-prefer-regexp-exec/node_modules/@typescript-eslint/eslint-plugin/dist/rules/prefer-regexp-exec.js:112:36)
at ruleErrorHandler (/tmp/buggy-prefer-regexp-exec/node_modules/eslint/lib/linter/linter.js:1077:28)
at /tmp/buggy-prefer-regexp-exec/node_modules/eslint/lib/linter/safe-emitter.js:45:58
at Array.forEach (<anonymous>)
at Object.emit (/tmp/buggy-prefer-regexp-exec/node_modules/eslint/lib/linter/safe-emitter.js:45:38)
at NodeEventGenerator.applySelector (/tmp/buggy-prefer-regexp-exec/node_modules/eslint/lib/linter/node-event-generator.js:297:26)
at NodeEventGenerator.applySelectors (/tmp/buggy-prefer-regexp-exec/node_modules/eslint/lib/linter/node-event-generator.js:326:22)
at NodeEventGenerator.enterNode (/tmp/buggy-prefer-regexp-exec/node_modules/eslint/lib/linter/node-event-generator.js:340:14)
at CodePathAnalyzer.enterNode (/tmp/buggy-prefer-regexp-exec/node_modules/eslint/lib/linter/code-path-analysis/code-path-analyzer.js:795:23)
After looking at the rule's implementation, the error is due to this particular line of code:
It calls the constructor function RegExp on the argument of String#match. However, the constructor throws a runtime error if the (statically known) regex is malformed.
I would argue that the rule should not break even if it's linting a string literal denoting a malformed regular expression. Instead, it should just keep silent and ignore the visited node. Therefore, a simple fix could be:
let regExp: RegExp;
try {
regExp = RegExp(argumentNode.value);
} catch {
return;
}Happy to provide a PR if the bug I reported and the fix I suggested make sense.
Reproduction Repository Link
https://github.com/yassin-kammoun-sonarsource/buggy-prefer-regexp-exec
Repro Steps
- clone the repo
npm installnpx eslint .
Versions
| package | version |
|---|---|
@typescript-eslint/eslint-plugin |
5.59.0 |
@typescript-eslint/parser |
5.59.0 |
TypeScript |
5.0.4 |
ESLint |
8.38.0 |
node |
18.12.1 |