Found the usage of undeclared variables JS-0125
Bug risk
5 months ago
—
5 months old
'expect' is not defined To fix this, add jest in
environment array of .deepsource.toml. Read more in our documentation https://deepsource.io/docs/analyzer/javascript 8import Adapter from 'enzyme-adapter-react-16';
9import {createSerializer} from 'enzyme-to-json';
10
11expect.addSnapshotSerializer(createSerializer({mode: 'deep'}));12
13Enzyme.configure({adapter: new Adapter()});
Description
Variables that aren't defined, but accessed may throw reference errors at runtime.
Potential ReferenceErrors may result from misspellings of variable and parameter names, or accidental implicit globals (for example, forgetting the var keyword in a for loop initializer).
Any reference to an undeclared variable causes a warning, unless the variable is explicitly mentioned in a /*global ...*/ comment, or specified in the globals key in the configuration file.
A common use case for these is if you intentionally use globals that are defined elsewhere (e.g. in a script sourced from HTML).
Bad Practice
const foo = someFunction();
const bar = a + 1; // 'a' is undeclared
Recommended
/*global someFunction, a*/
/*eslint no-undef: "error"*/
const foo = someFunction();
const bar = a + 1;