Add expose static method scenario and test

app/src/main/java/com/aria/refactortechniques/MainActivity.kt

@@ -1,7 +1,7 @@
 package com.aria.refactortechniques
 
-import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
+import androidx.appcompat.app.AppCompatActivity
 
 class MainActivity : AppCompatActivity() {
 

app/src/main/java/com/aria/refactortechniques/scenario/Coupon.kt

@@ -0,0 +1,6 @@
+package com.aria.refactortechniques.scenario
+
+data class Coupon(
+    val title: String = "Title",
+    val duration: Int = 100
+)

app/src/main/java/com/aria/refactortechniques/scenario/CouponPresenter.kt

@@ -0,0 +1,8 @@
+package com.aria.refactortechniques.scenario
+
+class CouponPresenter(val couponValidatorUseCase: CouponValidatorUseCase) {
+
+    fun setup(coupon: Coupon) {
+        couponValidatorUseCase.validate(coupon)
+    }
+}

app/src/main/java/com/aria/refactortechniques/scenario/CouponValidatorUseCase.kt

@@ -0,0 +1,8 @@
+package com.aria.refactortechniques.scenario
+
+const val MAX_TITLE_LENGTH = 100
+
+class CouponValidatorUseCase {
+
+    fun validate(coupon: Coupon) = coupon.title.length < MAX_TITLE_LENGTH
+}

app/src/main/java/com/aria/refactortechniques/solution/CouponPresenterSolution.kt

@@ -0,0 +1,12 @@
+package com.aria.refactortechniques.solution
+
+import com.aria.refactortechniques.scenario.Coupon
+
+class CouponPresenterSolution(
+    private val couponValidatorUseCaseSolution: CouponValidatorUseCaseSolution
+) {
+
+    fun setup(coupon: Coupon) {
+        couponValidatorUseCaseSolution.validate(coupon)
+    }
+}

app/src/main/java/com/aria/refactortechniques/solution/CouponValidatorUseCaseSolution.kt

@@ -0,0 +1,15 @@
+package com.aria.refactortechniques.solution
+
+import com.aria.refactortechniques.scenario.Coupon
+import com.aria.refactortechniques.scenario.MAX_TITLE_LENGTH
+
+class CouponValidatorUseCaseSolution {
+
+    fun validate(coupon: Coupon): Boolean {
+        return validateCoupon(coupon)
+    }
+
+    companion object {
+        fun validateCoupon(coupon: Coupon) = coupon.title.length < MAX_TITLE_LENGTH
+    }
+}

app/src/test/java/com/aria/refactortechniques/CouponValidatorUseCaseTest.kt

@@ -0,0 +1,34 @@
+package com.aria.refactortechniques
+
+import com.aria.refactortechniques.scenario.Coupon
+import com.aria.refactortechniques.solution.CouponPresenterSolution
+import com.aria.refactortechniques.solution.CouponValidatorUseCaseSolution
+import com.nhaarman.mockitokotlin2.given
+import org.junit.Before
+import org.junit.Test
+
+class CouponValidatorUseCaseSolutionTest {
+
+    private lateinit var sut: CouponPresenterSolution
+    private lateinit var couponValidatorUseCaseSolution: CouponValidatorUseCaseSolution
+
+    @Before
+    fun setup() {
+        sut = CouponPresenterSolution(couponValidatorUseCaseSolution)
+    }
+
+    @Test
+    fun `given valid coupon should validate it properly`() {
+        couponValidatorUseCaseSolution.validate(givenAnyCoupon())
+    }
+
+    @Test
+    fun `given Valid Coupon`() {
+        given(CouponValidatorUseCaseSolution.validateCoupon(givenAnyCoupon()))
+            .willReturn(true)
+    }
+
+    fun givenAnyCoupon(): Coupon {
+        return Coupon("Any", 100)
+    }
+}