org.scalatest.verbs.CanVerb.scala Maven / Gradle / Ivy
/*
* Copyright 2001-2013 Artima, Inc.
*
* 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.scalatest.verbs
import org.scalactic._
/**
* Provides an implicit conversion that adds can methods to String
* to support the syntax of FlatSpec, WordSpec, org.scalatest.fixture.FlatSpec,
* and fixture.WordSpec.
*
*
* For example, this trait enables syntax such as the following test registration in FlatSpec
* and fixture.FlatSpec:
*
*
*
* "A Stack (when empty)" can "be empty" in { ... }
* ^
*
*
*
* It also enables syntax such as the following shared test registration in FlatSpec
* and fixture.FlatSpec:
*
*
*
* "A Stack (with one item)" can behave like nonEmptyStack(stackWithOneItem, lastValuePushed)
* ^
*
*
*
* In addition, it supports the registration of subject descriptions in WordSpec
* and fixture.WordSpec, such as:
*
*
*
* "A Stack (when empty)" can { ...
* ^
*
*
*
* And finally, it also supportds the registration of subject descriptions with after words
* in WordSpec and fixture.WordSpec. For example:
*
*
*
* def provide = afterWord("provide")
*
* "The ScalaTest Matchers DSL" can provide {
* ^
*
*
*
* The reason this implicit conversion is provided in a separate trait, instead of being provided
* directly in FlatSpec, WordSpec, fixture.FlatSpec, and
* fixture.WordSpec, is primarily for design symmetry with ShouldVerb
* and MustVerb. Both ShouldVerb and MustVerb must exist
* as a separate trait because an implicit conversion provided directly would conflict
* with the implicit conversion that provides should or must methods on String
* in the Matchers and MustMatchers traits.
*
*
* @author Bill Venners
*/
trait CanVerb {
// This one can be final, because it isn't extended by anything in the matchers DSL.
/**
* This class supports the syntax of FlatSpec, WordSpec, fixture.FlatSpec,
* and fixture.WordSpec.
*
*
* This class is used in conjunction with an implicit conversion to enable can methods to
* be invoked on Strings.
*
*
* @author Bill Venners
*/
trait StringCanWrapperForVerb {
val leftSideString: String
val pos: source.Position
/**
* Supports test registration in FlatSpec and fixture.FlatSpec.
*
*
* For example, this method enables syntax such as the following in FlatSpec
* and fixture.FlatSpec:
*
*
*
* "A Stack (when empty)" can "be empty" in { ... }
* ^
*
*
*
* FlatSpec passes in a function via the implicit parameter that takes
* three strings and results in a ResultOfStringPassedToVerb. This method
* simply invokes this function, passing in leftSideString, the verb string
* "can", and right, and returns the result.
*
*/
def can(right: String)(implicit svsi: StringVerbStringInvocation): ResultOfStringPassedToVerb = {
svsi(leftSideString, "can", right, pos)
}
/**
* Supports shared test registration in FlatSpec and fixture.FlatSpec.
*
*
* For example, this method enables syntax such as the following in FlatSpec
* and fixture.FlatSpec:
*
*
*
* "A Stack (with one item)" can behave like nonEmptyStack(stackWithOneItem, lastValuePushed)
* ^
*
*
*
* FlatSpec and fixture.FlatSpec passes in a function via the implicit parameter that takes
* a string and results in a BehaveWord. This method
* simply invokes this function, passing in leftSideString, and returns the result.
*
*/
def can(right: BehaveWord)(implicit svbli: StringVerbBehaveLikeInvocation): BehaveWord = {
svbli(leftSideString, pos)
}
/**
* Supports the registration of subject descriptions in WordSpec
* and fixture.WordSpec.
*
*
* For example, this method enables syntax such as the following in WordSpec
* and fixture.WordSpec:
*
*
*
* "A Stack (when empty)" can { ...
* ^
*
*
*
* WordSpec passes in a function via the implicit parameter of type StringVerbBlockRegistration,
* a function that takes two strings and a no-arg function and results in Unit. This method
* simply invokes this function, passing in leftSideString, the verb string
* "can", and the right by-name parameter transformed into a
* no-arg function.
*
*/
def can(right: => Unit)(implicit fun: StringVerbBlockRegistration): Unit = {
fun(leftSideString, "can", pos, () => right)
}
/**
* Supports the registration of subject descriptions with after words
* in WordSpec and fixture.WordSpec.
*
*
* For example, this method enables syntax such as the following in WordSpec
* and fixture.WordSpec:
*
*
*
* def provide = afterWord("provide")
*
* "The ScalaTest Matchers DSL" can provide {
* ^
*
*
*
* WordSpec passes in a function via the implicit parameter that takes
* two strings and a ResultOfAfterWordApplication and results in Unit. This method
* simply invokes this function, passing in leftSideString, the verb string
* "can", and the ResultOfAfterWordApplication passed to can.
*
*/
def can(resultOfAfterWordApplication: ResultOfAfterWordApplication)(implicit swawr: SubjectWithAfterWordRegistration): Unit = {
swawr(leftSideString, "can", resultOfAfterWordApplication, pos)
}
}
import scala.language.implicitConversions
/**
* Implicitly converts an object of type String to a StringCanWrapper,
* to enable can methods to be invokable on that object.
*/
implicit def convertToStringCanWrapper(o: String)(implicit position: source.Position): StringCanWrapperForVerb =
new StringCanWrapperForVerb {
val leftSideString = o.trim
val pos = position
}
}