reinterpretAsCoverFormalsList()

in src/parser.ts [1606:1667]

• 56 lines of code
• 16 McCabe index (conditional complexity)

    reinterpretAsCoverFormalsList(expr) {
        let params = [expr];
        let options;

        let asyncArrow = false;
        switch (expr.type) {
            case Syntax.Identifier:
                break;
            case ArrowParameterPlaceHolder:
                params = expr.params;
                asyncArrow = expr.async;
                break;
            default:
                return null;
        }

        options = {
            simple: true,
            paramSet: {}
        };

        for (let i = 0; i < params.length; ++i) {
            const param = params[i];
            if (param.type === Syntax.AssignmentPattern) {
                if (param.right.type === Syntax.YieldExpression) {
                    if (param.right.argument) {
                        this.throwUnexpectedToken(this.lookahead);
                    }
                    param.right.type = Syntax.Identifier;
                    param.right.name = 'yield';
                    delete param.right.argument;
                    delete param.right.delegate;
                }
            } else if (asyncArrow && param.type === Syntax.Identifier && param.name === 'await') {
                this.throwUnexpectedToken(this.lookahead);
            }
            this.checkPatternParam(options, param);
            params[i] = param;
        }

        if (this.context.strict || !this.context.allowYield) {
            for (let i = 0; i < params.length; ++i) {
                const param = params[i];
                if (param.type === Syntax.YieldExpression) {
                    this.throwUnexpectedToken(this.lookahead);
                }
            }
        }

        if (options.message === Messages.StrictParamDupe) {
            const token = this.context.strict ? options.stricted : options.firstRestricted;
            this.throwUnexpectedToken(token, options.message);
        }

        return {
            simple: options.simple,
            params: params,
            stricted: options.stricted,
            firstRestricted: options.firstRestricted,
            message: options.message
        };
    }