/*
 * Copyright 2011 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.gradle.util

import spock.lang.*
import org.gradle.api.Action
import java.util.concurrent.Callable

class SwapperTest extends Specification {

    def originalValue = 1
    def value = originalValue
    def getter = { value }
    def setter = { this.value = it }

    def swap(newValue, whileSwapped) {
        new Swapper(getter as Callable, setter as Action).swap(newValue, whileSwapped as Callable)
    }
    
    def "can swap values"() {
        given:
        def newValue = 2
        def returnValue = 3
        
        expect:
        returnValue == swap(newValue) { 
            assert value == newValue
            returnValue
        } 
        
        and:
        value == originalValue
    }
    
    def "value is swapped back when exception thrown"() {        
        when:
        swap(2) { 
            throw new IllegalStateException()
        } 
        
        then:
        value == originalValue
        
        and:
        thrown IllegalStateException
        
    }
    
}