Fix and test class attribute handling in ElementExtensions.

Re-enabled previously commented-out logic for managing the "class" attribute in ElementExtensions to ensure proper updates and removals. Added comprehensive unit tests in `TestClassUpdate` to verify behavior, including class addition, removal, and name changes. Bumped the project version to 1.2.6.

build.gradle.kts

@@ -11,7 +11,7 @@ plugins {
 }
 
 group = "nl.astraeus"
-version = "1.2.5"
+version = "1.2.6"
 
 repositories {
   mavenCentral()

src/jsMain/kotlin/nl/astraeus/komp/ElementExtentions.kt

@@ -74,11 +74,9 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
         "checked" -> {
           checked = false
         }
-/*
         "class" -> {
           className = ""
         }
-*/
         "value" -> {
           this.value = ""
         }
@@ -86,6 +84,8 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
           removeAttribute(attributeName)
         }
       }
+    } else if (attributeName == "class") {
+      className = ""
     } else {
       removeAttribute(attributeName)
     }
@@ -95,11 +95,9 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
         "checked" -> {
           checked = "checked" == value
         }
-/*
         "class" -> {
           className = value
         }
-*/
         "value" -> {
           this.value = value
         }
@@ -107,6 +105,8 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
           setAttribute(attributeName, value)
         }
       }
+    } else if (attributeName == "class") {
+      className = value
     } else if (this.getAttribute(attributeName) != value) {
       setAttribute(attributeName, value)
     }

src/jsTest/kotlin/nl/astraeus/komp/TestClassUpdate.kt

@@ -0,0 +1,70 @@
+package nl.astraeus.komp
+
+import kotlinx.browser.document
+import kotlinx.html.div
+import kotlinx.html.classes
+import org.w3c.dom.HTMLDivElement
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+/**
+ * Test class for verifying class attribute updates and removals
+ */
+class ClassKomponent : Komponent() {
+    var includeClass = true
+    var className = "test-class"
+
+    override fun HtmlBuilder.render() {
+        div {
+            if (includeClass) {
+                classes = setOf(className)
+            }
+            +"Content"
+        }
+    }
+}
+
+class TestClassUpdate {
+
+    @Test
+    fun testClassRemoval() {
+        // Create a test component
+        val classComponent = ClassKomponent()
+        val div = document.createElement("div") as HTMLDivElement
+
+        // Render it
+        Komponent.create(div, classComponent)
+
+        // Verify initial state - should have the class
+        val contentDiv = div.querySelector("div")
+        println("[DEBUG_LOG] Initial DOM: ${div.printTree()}")
+        assertTrue(contentDiv?.classList?.contains("test-class") ?: false, "Div should have the class initially")
+
+        // Update to remove the class
+        classComponent.includeClass = false
+        classComponent.requestImmediateUpdate()
+
+        // Verify the class was removed
+        println("[DEBUG_LOG] After class removal: ${div.printTree()}")
+        assertFalse(contentDiv?.classList?.contains("test-class") ?: true, "Class should be removed after update")
+
+        // Add the class back
+        classComponent.includeClass = true
+        classComponent.requestImmediateUpdate()
+
+        // Verify the class was added back
+        println("[DEBUG_LOG] After class added back: ${div.printTree()}")
+        assertTrue(contentDiv?.classList?.contains("test-class") ?: false, "Class should be added back")
+
+        // Change the class name
+        classComponent.className = "new-class"
+        classComponent.requestImmediateUpdate()
+
+        // Verify the class was changed
+        println("[DEBUG_LOG] After class name change: ${div.printTree()}")
+        assertFalse(contentDiv?.classList?.contains("test-class") ?: true, "Old class should be removed")
+        assertTrue(contentDiv?.classList?.contains("new-class") ?: false, "New class should be added")
+    }
+}

src/wasmJsMain/kotlin/nl/astraeus/komp/ElementExtentions.kt

@@ -73,11 +73,9 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
         "checked" -> {
           checked = false
         }
-/*
         "class" -> {
           className = ""
         }
-*/
         "value" -> {
           this.value = ""
         }
@@ -85,6 +83,8 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
           removeAttribute(attributeName)
         }
       }
+    } else if (attributeName == "class") {
+      className = ""
     } else {
       removeAttribute(attributeName)
     }
@@ -94,11 +94,9 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
         "checked" -> {
           checked = "checked" == value
         }
-/*
         "class" -> {
           className = value
         }
-*/
         "value" -> {
           this.value = value
         }
@@ -106,6 +104,8 @@ internal fun Element.setKompAttribute(attributeName: String, value: String?) {
           setAttribute(attributeName, value)
         }
       }
+    } else if (attributeName == "class") {
+      className = value
     } else if (this.getAttribute(attributeName) != value) {
       setAttribute(attributeName, value)
     }