Pembuatan Direktori test untuk Unit Testing pada fungsi calculateBMI dan calculateBMICategory

app/build.gradle.kts

@@ -73,8 +73,11 @@ dependencies {
     implementation("androidx.compose.ui:ui-tooling-preview")
     implementation("androidx.core:core-ktx:1.15.0")
     implementation("androidx.lifecycle:lifecycle-runtime-ktx:2.8.7")
+    implementation("junit:junit:4.12")
 
+    // Unit Testing
     testImplementation("junit:junit:4.13.2")
+    testImplementation("org.junit.jupiter:junit-jupiter:5.8.1")
 
     androidTestImplementation(platform("androidx.compose:compose-bom:2024.12.01"))
     androidTestImplementation("androidx.compose.ui:ui-test-junit4")

app/src/main/java/com/example/bmicalculator/MainActivity.kt

@@ -65,8 +65,6 @@ import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import com.example.bmicalculator.ui.theme.BMICalculatorTheme
 import java.text.DecimalFormat
-import java.text.NumberFormat
-import java.util.Locale
 import kotlin.math.pow
 
 class MainActivity : ComponentActivity() {
@@ -208,9 +206,9 @@ fun UnitUSCFormulaRow(
  *
  * Catatan: tambahkan unit test untuk kalkulasi BMI ini
  */
-private fun calculateBMI(BmiHeight: Double, BmiWeight: Double, unitUSC: Boolean): String {
+fun calculateBMI(BmiHeight: Double, BmiWeight: Double, unitUSC: Boolean): String {
     if (BmiHeight <= 0 || BmiWeight <= 0){
-        return "0"
+        return "0.0"
     }
 
     val heightInMeter = BmiHeight/100 // konversi centimeter ke meter
@@ -223,6 +221,7 @@ private fun calculateBMI(BmiHeight: Double, BmiWeight: Double, unitUSC: Boolean)
     val df = DecimalFormat("#.#")
     return df.format(bmi)
 }
+
 /**
  * Calculates the BMI Category
  * bmi < 18.5 -> Underweight
@@ -232,7 +231,7 @@ private fun calculateBMI(BmiHeight: Double, BmiWeight: Double, unitUSC: Boolean)
  *
  * Catatan: tambahkan unit test untuk kalkulasi BMI ini
  */
-private fun calculateBMICategory(bmi: String): String {
+fun calculateBMICategory(bmi: String): String {
     val bmiValue = bmi.replace(",", ".").toDoubleOrNull() ?: return ""
 
     return when {
@@ -246,7 +245,7 @@ private fun calculateBMICategory(bmi: String): String {
 
 @Preview(showBackground = true)
 @Composable
-fun TipTimeLayoutPreview() {
+fun BMICalculatorLayoutPreview() {
     BMICalculatorTheme {
         BMICalculatorLayout()
     }

app/src/test/java/calculateBMITest.kt

@@ -0,0 +1,88 @@
+package com.example.bmicalculator
+
+import org.junit.Assert.*
+import org.junit.Test
+
+class CalculateBMITest {
+
+    // Test BMI SI Metric (Kg, Cm)
+    @Test
+    fun testCalculateBMI_SI_Normal() {
+        val result = calculateBMI(170.0, 65.0, false) // 170cm, 65kg
+        assertEquals("22.5", result) // Expected BMI ≈ 22.5
+    }
+
+    @Test
+    fun testCalculateBMI_SI_Zero() {
+        val result = calculateBMI(0.0, 0.0, false)
+        assertEquals("0.0", result)
+    }
+
+    @Test
+    fun testCalculateBMI_SI_Underweight() {
+        val result = calculateBMI(170.0, 50.0, false) // 170cm, 50kg
+        assertEquals("17.3", result) // Expected BMI ≈ 17.3
+    }
+
+    @Test
+    fun testCalculateBMI_SI_Overweight() {
+        val result = calculateBMI(170.0, 80.0, false) // 170cm, 80kg
+        assertEquals("27.7", result) // Expected BMI ≈ 27.7
+    }
+
+    // Test BMI USC Units (Pound, Inch)
+    @Test
+    fun testCalculateBMI_USC_Normal() {
+        val result = calculateBMI(70.0, 154.0, true) // 70 inch, 154 lbs
+        assertEquals("22.1", result) // Expected BMI ≈ 22.1
+    }
+
+    @Test
+    fun testCalculateBMI_USC_Zero() {
+        val result = calculateBMI(0.0, 0.0, true)
+        assertEquals("0.0", result)
+    }
+
+    // Test BMI Category
+    @Test
+    fun testCalculateBMICategory_Underweight() {
+        val result = calculateBMICategory("17.5")
+        assertEquals("Underweight", result)
+    }
+
+    @Test
+    fun testCalculateBMICategory_Normal() {
+        val result = calculateBMICategory("22.5")
+        assertEquals("Normal", result)
+    }
+
+    @Test
+    fun testCalculateBMICategory_Overweight() {
+        val result = calculateBMICategory("27.5")
+        assertEquals("Overweight", result)
+    }
+
+    @Test
+    fun testCalculateBMICategory_Obesity() {
+        val result = calculateBMICategory("32.0")
+        assertEquals("Obesity", result)
+    }
+
+    @Test
+    fun testCalculateBMICategory_Zero() {
+        val result = calculateBMICategory("0.0")
+        assertEquals("", result)
+    }
+
+    @Test
+    fun testCalculateBMICategory_EmptyString() {
+        val result = calculateBMICategory("")
+        assertEquals("", result)
+    }
+
+    @Test
+    fun testCalculateBMICategory_WithComma() {
+        val result = calculateBMICategory("22,5") // Test dengan koma
+        assertEquals("Normal", result)
+    }
+}