Repository: eslint/eslint
File: lib/rules/no-unused-vars.js (JavaScript)

Code before:
                    // skip implicit "arguments" variable
                    if (scope.type === "function" && variable.name === "arguments" && variable.identifiers.length === 0) {
                        continue;
                    }

                    // explicit global variables don't have definitions.
                    const def = variable.defs[0];

                    if (def) {
                        const type = def.type;
                        const refUsedInArrayPatterns = variable.references.some(ref => ref.identifier.parent.type === "ArrayPattern");

                        // skip elements of array destructuring patterns
                        if (
                            (
                                def.name.parent.type === "ArrayPattern" ||
                                refUsedInArrayPatterns
                            ) &&
                            config.destructuredArrayIgnorePattern &&
                            config.destructuredArrayIgnorePattern.test(def.name.name)
                        ) {
                            continue;
                        }

                        if (type === "ClassName") {
                            const hasStaticBlock = def.node.body.body.filter(node => node.type === "StaticBlock");

                            if (config.ignoreClassWithStaticInitBlock && hasStaticBlock) {
                                continue;
                            }
                        }

                        // skip catch variables
                        if (type === "CatchClause") {
                            if (config.caughtErrors === "none") {
                                continue;
                            }

                            // skip ignored parameters
                            if (config.caughtErrorsIgnorePattern && config.caughtErrorsIgnorePattern.test(def.name.name)) {
                                continue;
                            }
                        } else if (type === "Parameter") {

                            // skip any setter argument
                            if ((def.node.parent.type === "Property" || def.node.parent.type === "MethodDefinition") && def.node.parent.kind === "set") {
                                continue;
                            }

                            // if "args" option is "none", skip any parameter
                            if (config.args === "none") {

Review comment (suggestion):
```suggestion
                            const hasStaticBlock = def.node.body.body.some(node => node.type === "StaticBlock");
```

`filter` always returns an array, so this would always be truthy.

```js
/* eslint no-unused-vars: ["error", { ignoreClassWithStaticInitBlock: true }] */

class C {} // false negative
```

We should also add some tests where this option is `true` and class doesn't have static blocks.

Code after:
                    // skip implicit "arguments" variable
                    if (scope.type === "function" && variable.name === "arguments" && variable.identifiers.length === 0) {
                        continue;
                    }

                    // explicit global variables don't have definitions.
                    const def = variable.defs[0];

                    if (def) {
                        const type = def.type;
                        const refUsedInArrayPatterns = variable.references.some(ref => ref.identifier.parent.type === "ArrayPattern");

                        // skip elements of array destructuring patterns
                        if (
                            (
                                def.name.parent.type === "ArrayPattern" ||
                                refUsedInArrayPatterns
                            ) &&
                            config.destructuredArrayIgnorePattern &&
                            config.destructuredArrayIgnorePattern.test(def.name.name)
                        ) {
                            continue;
                        }

                        if (type === "ClassName") {
                            const hasStaticBlock = def.node.body.body.some(node => node.type === "StaticBlock");

                            if (config.ignoreClassWithStaticInitBlock && hasStaticBlock) {
                                continue;
                            }
                        }

                        // skip catch variables
                        if (type === "CatchClause") {
                            if (config.caughtErrors === "none") {
                                continue;
                            }

                            // skip ignored parameters
                            if (config.caughtErrorsIgnorePattern && config.caughtErrorsIgnorePattern.test(def.name.name)) {
                                continue;
                            }
                        } else if (type === "Parameter") {

                            // skip any setter argument
                            if ((def.node.parent.type === "Property" || def.node.parent.type === "MethodDefinition") && def.node.parent.kind === "set") {
                                continue;
                            }

                            // if "args" option is "none", skip any parameter
                            if (config.args === "none") {