Test
package com.utrecht.numbersequences
import org.scalatest.FunSuite
import org.scalatest.BeforeAndAfter
import org.scalatest.mock.MockitoSugar
import org.mockito.Mockito._
class NumberSequencesTests extends FunSuite with BeforeAndAfter with MockitoSugar {
test("testCity") {
NumberSequences.city_("utrecht")
assert("utrecht" === NumberSequences.city())
}
}
Code
package com.utrecht.numbersequences
import scala.collection.immutable.Stream.consWrapper
object NumberSequences {
var _city: String = null
def city_=(_city:String) = this._city = _city
def city = this._city
}
Outcome
value not a member of object
not enough arguments for method apply: (index: Int)Char in class StringOps
test
[info] Compiling 1 Scala source to C:\path\to\developme
nt\scalaNumberSequences\target\scala-2.10\test-classes...
[error] C:\path\to\development\scalaNumberSequences\src
\test\scala\com\utrecht\numbersequences\NumberSequencesTest.scala:32: value city
_ is not a member of object com.utrecht.numbersequences.NumberSequences
[error] NumberSequences.city_("utrecht")
[error] ^
[error] C:\path\to\development\scalaNumberSequences\src
\test\scala\com\utrecht\numbersequences\NumberSequencesTest.scala:33: not enough
arguments for method apply: (index: Int)Char in class StringOps.
[error] Unspecified value parameter index.
[error] assert("utrecht" === NumberSequences.city())
[error] ^
[error] two errors found
[error] (test:compile) Compilation failed
[error] Total time: 1 s, completed Aug 10, 2014 5:52:16 PM
NumberSequences.city_=("utrecht")
//OR
NumberSequences.city = "utrecht"
but not:
NumberSequences.city_("utrecht") // city_ is not a method existing in the object
Related
I am reading this tutorial on tagless final.
Based on this I have defined my dependencies as
object Dependencies {
lazy val scalaTest = "org.scalatest" %% "scalatest" % "3.0.5"
lazy val cats = "org.typelevel" %% "cats-core" % "1.2.0"
lazy val monix = "io.monix" %% "monix" % "2.3.3"
lazy val monixCats = "io.monix" %% "monix-cats" % "2.3.3"
}
The following is my code
// future
import scala.concurrent.ExecutionContext.Implicits.global
import scala.concurrent._
import scala.concurrent.duration._
// cats
import cats.Monad
import cats.implicits._
// monix
import monix.eval.Task
import monix.cats._
import monix.cats.reverse._
trait ProductRepository[M[_]] {
def findProduct(productId: ProductId) : M[Option[Product]]
def saveProduct(product: Product) : M[Unit]
def incrementProductSales(productId: ProductId, quantity: Long) : M[Unit]
}
class ProductRepositoryWithFuture extends ProductRepository[Future] {
def findProduct(productId: ProductId) : Future[Option[Product]] = {
Future.successful(Some(Product(productId, "foo")))
}
def saveProduct(product: Product) : Future[Unit] = {
Future.successful()
}
def incrementProductSales(productId: ProductId, quanity: Long) : Future[Unit] = {
Future.successful()
}
}
class ProductRepositoryWithTask extends ProductRepository[Task] {
def findProduct(productId: ProductId) : Task[Option[Product]] = {
Task.now(Some(Product(productId, "foo")))
}
def saveProduct(product: Product) : Task[Unit] = {
Task.unit
}
def incrementProductSales(productId: ProductId, quantity: Long) : Task[Unit] = {
Task.unit
}
}
But I get bunch of errors. It seems that the version of cats which I am using is not compatible with the one Monix uses.
I also tried to remove my cats dependency and just imported monix so that monix pulls in its own version of cats. but even that doesn't compile.
error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:54:24: Symbol 'type cats.MonadFilter' is missing fromthe classpath.
[error] This symbol is required by 'method monix.cats.MonixToCatsCore7.monixToCatsMonadFilter'.
[error] Make sure that type MonadFilter is in your classpath and check for conflicting dependencies with `-Ylog-classpath`.
[error] A full rebuild may help if 'MonixToCatsCore7.class' was compiled against an incompatible version of cats.
[error] repo.findProduct(id).flatMap{
[error] ^
[error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:54:23: diverging implicit expansion for type monix.types.Comonad[M]
[error] starting with method catsToMonixComonad in trait CatsCoreToMonix5
[error] repo.findProduct(id).flatMap{
[error] ^
[error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:54:28: value flatMap is not a member of type parameter M[Option[example.Application.Product]]
[error] repo.findProduct(id).flatMap{
[error] ^
[error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:56:30: value copy is not a member of Any
[error] val newProduct = p.copy(name = name)
[error] ^
[error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:56:40: reassignment to val
[error] val newProduct = p.copy(name = name)
[error] ^
[error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:57:27: diverging implicit expansion for type monix.types.MonadError[M,E]
[error] starting with method catsToMonixMonadError in trait CatsCoreToMonix3
[error] repo.saveProduct(newProduct).map(_ => Some(p))
[error] ^
[error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:57:40: value map is not a member of type parameter M[Unit]
[error] repo.saveProduct(newProduct).map(_ => Some(p))
[error] ^
[error] /Users/foobar/code/tagless/src/main/scala/example/Hello.scala:59:16: diverging implicit expansion for type cats.Comonad[M]
[error] starting with method monixToCatsComonad in trait MonixToCatsCore5
[error] Monad[M].pure(None)
[error] ^
[error] 8 errors found
The errors are caused by incompatibilities between your dependencies.
For example monix 2.3.3 depends on cats 0.9.0 while you're trying to use 1.2.0 which is binary incompatible.
You should try either upgrading monix to 3.x or downgrading cats to 0.9.0.
P.S. The transition from cats 0.9.0 to 1.x has a lot of breaking changes and you have to make sure that all libraries you're using are compiled against the same (or at least binary compatible) version of cats.
Here is an example from the scala.rx doc:
package tutorial.webapp
import rx.core.{Rx, Var}
import rx._
import rx.ops._
import scala.concurrent.Promise
import scala.concurrent.duration._
import scala.scalajs.js.JSApp
import scala.scalajs.js.annotation.JSExport
import scala.concurrent.ExecutionContext.Implicits.global
/**
* Created by IDEA on 29/10/15.
*/
object RxAddtionalOps extends JSApp {
#JSExport
override def main(): Unit = {
mapDemo
filterDemo
asyncDemo
async2
timer1
}
def delay1: Unit = {
val a = Var(10)
val b = a.delay(250 millis)
a() = 5
println(b())
eventually{
println(b)
}
}
}
I got this error on sbt when compiling:
[error] /Users/kaiyin/personal_config_bin_files/workspace/scalajsHandson/src/main/scala/tutorial/webapp/RxAddtionalOps.scala:43: not found: value eventually
[error] eventually{
[error] ^
[error] one error found
[error] (compile:compileIncremental) Compilation failed
[error] Total time: 1 s, completed 30 oct. 2015 11:15:07
Where does the eventually function come from? Am I missing any imports?
It's defined in utest, which is a author's framework for tests. Since it's a test dependency it doesn't come bundled with scalarx. BTW, the very same functionality presented in scalatest.
I'm new to scala but I'm trying to add some tests to a simple file. The problem is that when I try to import the object into the test I get "error: not found: value"
PerfectNumberImperative.scala
package perfectImperative
package object perfectImperative{
def main(args: Array[String]){
perfectImperative(args(0).toInt)
}
def perfectImperative(input: Int): Boolean = {
var evaluation = (for (possibleFactor <-1 to input if (input % possibleFactor == 0)) yield possibleFactor).sum == input*2
return evaluation
}
}
PerfectNumberSpec.scala
import org.scalatest.FlatSpec
import perfectImperative._
class PerfectNumberSpec extends FlatSpec {
it should "return true for 6" in {
assert(perfectImperative.perfectImperative(6))
}
}
[error] C:\Users\Daniel\PerfectNumbersScala\src\test\scala\PerfectNumberSpec.scala:2: not found: object perfectImperative
[error] import perfectImperative._
[error] ^
[error] C:\Users\Daniel\PerfectNumbersScala\src\test\scala\PerfectNumberSpec.scala:6: not found: value perfectImperative
[error] assert(perfectImperative.perfectImperative(6))
[error] ^
[error] two errors found
[error] (test:compileIncremental) Compilation failed
[error] Total time: 2 s, completed Sep 16, 2015 2:30:38 AM
I would appreciate if someone could point me in the right direction.
I am trying to create a Scala macro that will generate an object - something like
object SomeEnum {
sealed abstract class Enum(name: String)
case object Option1 extends Enum("option1")
case object Option2 extends Enum("option2")
private val elements: Seq[Enum] = Seq(Option1, Option2)
def apply(code: String): Enum = {
...
}
}
I thought I might be able to create a macro createEnum, so I could just put
createEnum("SomeEnum", "Option1", "Option2") into my code and have it generate. Seems like it's calling out for a macro.
But I must not be understanding macros. I am using Scala 2.11.6, and just to try to get something working, I created the following:
object createEnumObj {
def createEnumImpl(c: scala.reflect.macros.whitebox.Context)(ename: c.Expr[String]): c.universe.ModuleDef = {
import c.universe._
val Literal(Constant(s_ename: String)) = ename.tree
val oname = TermName(s_ename)
val barLine = q"val bar: Int = 5"
q"object $oname { $barLine }"
}
def createEnum(ename: String): Unit = macro createEnumImpl
}
This is in a separate project - everything seems to be compiling for it OK.
If I stick a call to createEnumObj.createEnum into some source and try to compile that, I get a billion lines (give or take a few) of exception output, which seems to repeat something like this:
[error] (main/compile:compile) java.lang.AssertionError: assertion failed:
[error] object foo extends scala.AnyRef {
[error] def <init>() = {
[error] super.<init>();
[error] ()
[error] };
[error] val bar: Int = 5
[error] }
[error] while compiling: /Users/bob/ICL/ironcore-id/src/main/scala/package.scala
[error] during phase: typer
[error] library version: version 2.11.6
[error] compiler version: version 2.11.6
[error] reconstructed args: -Xfuture ...
error]
[error] last tree to typer: term foo
[error] tree position: line 8 of /Users/bob/ICL/ironcore-id/src/main/scala/package.scala
[error] symbol: <none>
[error] symbol definition: <none> (a NoSymbol)
[error] symbol package: <none>
[error] symbol owners:
[error] call site: <none> in <none>
[error]
[error] == Source file context for tree position ==
[error]
[error] 5 type DateTime = Int
[error] 6
[error] 7 createEnumObj.createEnum("foo")
[error] 8
[error] 9 }
[error] Total time: 2 s, completed Jun 18, 2015 2:46:05 PM
What I am trying to do doesn't seem too dissimilar to this question, but I'm obviously missing something. Any ideas about how to accomplish this would be gratefully accepted.
Thanks,
Bob
Code
Test
package com.utrecht.numbersequences
import org.scalatest.FunSuite
import org.scalatest.BeforeAndAfter
import org.scalatest.mock.MockitoSugar
import org.mockito.Mockito._
class NumberSequencesTests extends FunSuite with BeforeAndAfter with MockitoSugar {
test("randomInteger") {
val m = mock[NumberSequences]
when(m.randomInteger(5)).thenReturn(5)
assert(5 === m.randomInteger(5))
}
test("squareRoot") {
assert(NumberSequences.squareRoot(25) === 5)
}
}
Main
package com.utrecht.numbersequences
import scala.collection.immutable.Stream.consWrapper
class NumberSequences {
def randomInteger(a: Int) : Int = {
scala.util.Random.nextInt(a) + 1
}
def squareRoot(a: Double) : Double = {
math.sqrt(a)
}
}
Outcome
Expected
> test
[info] NumberSequencesTests:
[info] - randomInteger
[info] - squareRoot
[info] Passed: Total 2, Failed 0, Errors 0, Passed 2
[success] Total time: 1 s, completed Aug 10, 2014 11:46:44 AM
>
Current
In order to test squareRoot the NumberSequences class needs to be changed into an object. Once this has been done, the squareRoot can be tested, but the mock fails. Once this has been reversed, the mock test passes, but the squareRoot test fails again.
> test
[info] Compiling 1 Scala source to C:\path\to\developme
nt\scalaNumberSequences\target\scala-2.10\test-classes...
[error] C:\path\to\scalaNumberSequences\src
\test\scala\com\utrecht\numbersequences\NumberSequencesTest.scala:16: not found:
value NumberSequences
[error] assert(NumberSequences.squareRoot(25) === 5)
[error] ^
[error] one error found
[error] (test:compile) Compilation failed
[error] Total time: 1 s, completed Aug 10, 2014 11:47:13 AM
>
You have to instantiate a NumberSequences object, since it's a class, not an object or companion object.
assert(new NumberSequences().squareRoot(25) === 5)
To use this syntax:
assert(NumberSequences.squareRoot(25) === 5)
you would need this:
object NumberSequences {
def squareRoot(a: Double) : Double = {
math.sqrt(a)
}
}
But since you need to mock it (in the first test), I would rather use the first solution: instantiating the class.