Added assertComponents test helper, fixed #8

Author: viktor-podzigun

showcase/src/test/scala/scommons/react/showcase/ReactFragmentDemoSpec.scala

@@ -11,15 +11,15 @@ class ReactFragmentDemoSpec extends TestSpec with TestRendererUtils {
     val comp = <(ReactFragmentDemo())(^.wrapped := props)()
 
     //when
-    val results = createTestRenderer(comp).root.children.toList
+    val result = createTestRenderer(comp).root
 
     //then
-    inside(results) { case List(child1, child2, child3, child4) =>
-      assertNativeComponent(child1, <.div()("Item #1"))
-      assertNativeComponent(child2, <.div()("test 1"))
-      assertNativeComponent(child3, <.div()("Item #2"))
-      assertNativeComponent(child4, <.div()("test 2"))
-    }
+    assertComponents(result.children, List(
+      <.div()("Item #1"),
+      <.div()("test 1"),
+      <.div()("Item #2"),
+      <.div()("test 2")
+    ))
   }
 
   it should "render as child component" in {

test/src/main/scala/scommons/react/test/util/TestRendererUtils.scala

@@ -2,7 +2,7 @@ package scommons.react.test.util
 
 import io.github.shogowada.scalajs.reactjs.elements.ReactElement
 import org.scalactic.source.Position
-import org.scalatest.{Assertion, Succeeded}
+import org.scalatest.{Assertion, Assertions, Succeeded}
 import scommons.react.{ReactClass, UiComponent}
 import scommons.react.test.raw
 import scommons.react.test.raw.{TestInstance, TestRenderer}
@@ -11,7 +11,7 @@ import scommons.react.test.util.TestRendererUtils.UiComponentMock
 
 import scala.scalajs.js
 
-trait TestRendererUtils {
+trait TestRendererUtils extends Assertions {
 
   def mockUiComponent[T](name: String): UiComponent[T] = UiComponentMock[T](name)
 
@@ -61,6 +61,24 @@ trait TestRendererUtils {
     utils.assertComponent(result, expectedComp)(assertProps, assertChildren)
   }
 
+  def assertComponents(results: js.Array[TestInstance],
+                       expectedList: List[ReactElement]
+                      )(implicit pos: Position): Assertion = {
+
+    val resultCount = results.length
+    val expectedCount = expectedList.size
+    if (resultCount != expectedCount) {
+      fail(s"Result components count($resultCount) doesn't match expected count($expectedCount)")
+    }
+
+    expectedList.foldLeft(0) { (i, expected) =>
+      assertNativeComponent(results(i), expected)
+      i + 1
+    }
+    
+    Succeeded
+  }
+
   def assertNativeComponent(result: TestInstance,
                             expectedElement: ReactElement
                            )(implicit pos: Position): Assertion = {

test/src/test/scala/scommons/react/test/util/TestRendererUtilsSpec.scala

@@ -1,6 +1,7 @@
 package scommons.react.test.util
 
 import io.github.shogowada.scalajs.reactjs.elements.ReactElement
+import org.scalatest.exceptions.TestFailedException
 import scommons.react._
 import scommons.react.hooks._
 import scommons.react.test.raw.TestInstance
@@ -99,6 +100,40 @@ class TestRendererUtilsSpec extends RendererUtilsSpec[TestInstance]
       })
     })
   }
+
+  it should "fail if wrong number of components when assertComponents" in {
+    //given
+    val comp = testRender(<(comp2Class)(^.wrapped := Comp2Props(true))())
+
+    //when
+    val e = the[TestFailedException] thrownBy {
+      assertComponents(comp.children, List(
+        <(TestComp())(^.wrapped := Comp1Props(1))(
+          <.p(^.className := "test1")("test2 child1")
+        )
+      ))
+    }
+
+    //then
+    e.getMessage shouldBe "Result components count(2) doesn't match expected count(1)"
+  }
+
+  it should "assert children when assertComponents" in {
+    //given
+    val result = createTestRenderer(<(comp2Class)(^.wrapped := Comp2Props(true))()).root
+
+    //when & then
+    assertComponents(result.children, List(
+      <.div(^.className := "test2")(
+        <(TestComp())(^.wrapped := Comp1Props(1))(
+          <.p(^.className := "test1")("test2 child1")
+        ),
+        <(TestComp())(^.wrapped := Comp1Props(2))(
+          <.p(^.className := "test1")("test2 child2")
+        )
+      )
+    ))
+  }
 }
 
 object TestRendererUtilsSpec {