adaptive-expressions/src/builtinFunctions/contains.ts

Common Expression Language

/**
 * @module adaptive-expressions
 */
/**
 * Copyright (c) Microsoft Corporation. All rights reserved.
 * Licensed under the MIT License.
 */

import { Expression } from '../expression';
import { ExpressionEvaluator, ValueWithError } from '../expressionEvaluator';
import { ExpressionType } from '../expressionType';
import { FunctionUtils } from '../functionUtils';
import { InternalFunctionUtils } from '../functionUtils.internal';
import { MemoryInterface } from '../memory/memoryInterface';
import { Options } from '../options';
import { ReturnType } from '../returnType';

/**
 * Check whether a collection has a specific item. Return true if the item is found, or return false if not found.
 * This function is case-sensitive.
 */
export class Contains extends ExpressionEvaluator {
    /**
     * Initializes a new instance of the [Contains](xref:adaptive-expressions.Contains) class.
     */
    constructor() {
        super(ExpressionType.Contains, Contains.evaluator, ReturnType.Boolean, FunctionUtils.validateBinary);
    }

    /**
     * @private
     */
    private static evaluator(expression: Expression, state: MemoryInterface, options: Options): ValueWithError {
        let found = false;
        const { args, error: childrenError } = FunctionUtils.evaluateChildren(expression, state, options);
        let error = childrenError;
        if (!error) {
            if (typeof args[0] === 'string' && typeof args[1] === 'string') {
                found = args[0].includes(args[1]);
            } else if (Array.isArray(args[0])) {
                for (const item of args[0]) {
                    if (FunctionUtils.commonEquals(item, args[1])) {
                        found = true;
                        break;
                    }
                }
            } else if (typeof args[1] === 'string') {
                let value: any;
                ({ value, error } = InternalFunctionUtils.accessProperty(args[0], args[1]));
                found = !error && value !== undefined;
            }
        }

        return { value: found, error: undefined };
    }
}