Implement _setValue() which pretends that the value came from the client

karibu-testing-v10-groovy/src/main/groovy/com/github/mvysny/kaributesting/v10/groovy/HasValueUtils.groovy

@@ -35,6 +35,18 @@ class HasValueUtils {
         HasValueUtilsKt.set_value(self, value)
     }
 
+    /**
+     * Sets the value of given component, but only if it is actually possible to do so by the user.
+     * If the component is read-only or disabled, an exception is thrown.
+     * <p></p>
+     * The function fires the value change event; the {@link HasValue.ValueChangeEvent#isFromClient()} will
+     * mirror the <code>fromClient</code> parameter which defaults to `true` indicating that the event came from the client.
+     * @throws IllegalStateException if the field was not visible, not enabled or was read-only.
+     */
+    static <V> void _setValue(@NotNull HasValue<?, V> self, @Nullable V value, boolean fromClient = true) {
+        HasValueUtilsKt._setValue(self, value, fromClient)
+    }
+
     /**
      * Fires a value change event which "comes from the client".
      * <p></p>

karibu-testing-v10/README.md

@@ -952,11 +952,13 @@ all the above items prior setting the new value:
 * Java: `LocatorJ._setValue(textField, "42");`
 
 Changing the value fires the ValueChangeEvent with `isFromClient` set to false.
-However, sometimes you need to fire a "client-side"/"isfromuser" value-change event,
+However, sometimes you need to fire a "client-side"/"isfromuser"/"userOriginated" value-change event,
 to test a code reacting to such events. In such case please use:
 
-* Kotlin, Groovy: `textField._fireValueChange()`
-* Java: `LocatorJ._fireValueChange(textField)`
+* Kotlin, Groovy: `textField._fireValueChange()` is able to fire value change event with `isFromClient` set to true.
+  * Java: `LocatorJ._fireValueChange(textField)`
+* Better: `textField._setValue("foo")` sets the value as if changed by the client.
+  * Java: `LocatorJ._setValue(textField, "foo", true);`
 
 ### Firing DOM Events
 

karibu-testing-v10/kt10-tests/src/main/kotlin/com/github/mvysny/kaributesting/v10/HasValueTest.kt

@@ -86,5 +86,29 @@ internal fun DynaNodeGroup.hasValueTestbatch() {
             tf._fireValueChange()
             expect(true) { called }
         }
+        group("from client") {
+            test("TextField") {
+                val tf = TextField()
+                var called = false
+                tf.addValueChangeListener {
+                    expect(false) { called }
+                    expect(true) { it.isFromClient }
+                    called = true
+                }
+                tf._setValue("foo")
+                expect(true) { called }
+            }
+            test("CheckBox") {
+                val tf = Checkbox()
+                var called = false
+                tf.addValueChangeListener {
+                    expect(false) { called }
+                    expect(true) { it.isFromClient }
+                    called = true
+                }
+                tf._setValue(true)
+                expect(true) { called }
+            }
+        }
     }
 }

karibu-testing-v10/src/main/java/com/github/mvysny/kaributesting/v10/LocatorJ.java

@@ -112,6 +112,18 @@ public static <V> void _setValue(@NotNull HasValue<?, V> receiver, @Nullable V v
         HasValueUtilsKt.set_value(receiver, value);
     }
 
+    /**
+     * Sets the value of given component, but only if it is actually possible to do so by the user.
+     * If the component is read-only or disabled, an exception is thrown.
+     * <p></p>
+     * The function fires the value change event; the {@link HasValue.ValueChangeEvent#isFromClient()} will
+     * mirror the <code>fromClient</code> parameter.
+     * @throws IllegalStateException if the field was not visible, not enabled or was read-only.
+     */
+    static <V> void _setValue(@NotNull HasValue<?, V> self, @Nullable V value, boolean fromClient) {
+        HasValueUtilsKt._setValue(self, value, fromClient);
+    }
+
     /**
      * Fires a value change event which "comes from the client".
      * <p></p>

karibu-testing-v10/src/main/kotlin/com/github/mvysny/kaributesting/v10/HasValueUtils.kt

@@ -3,14 +3,15 @@ package com.github.mvysny.kaributesting.v10
 import com.vaadin.flow.component.AbstractField
 import com.vaadin.flow.component.Component
 import com.vaadin.flow.component.HasValue
+import com.vaadin.flow.component.internal.AbstractFieldSupport
 
 /**
  * Sets the value of given component, but only if it is actually possible to do so by the user.
  * If the component is read-only or disabled, an exception is thrown.
  *
  * Modification of this property fires the value change event; the [HasValue.ValueChangeEvent.isFromClient] will
- * return `false` indicating that the event came from the server. If this is not desired,
- * depending on your code, it may be
+ * return `false` indicating that the event came from the server. If this is not desired, use [_setValue];
+ * alternatively it may be
  * possible to call [_fireValueChange] with `fromClient=true` instead.
  * @throws IllegalStateException if the field was not visible, not enabled or was read-only.
  */
@@ -21,6 +22,30 @@ public var <V> HasValue<*, V>._value: V?
         value = v
     }
 
+public val <T> AbstractField<*, T>._fieldSupport: AbstractFieldSupport<*, T> get() {
+    val f = AbstractField::class.java.getDeclaredField("fieldSupport")
+    f.isAccessible = true
+    @Suppress("UNCHECKED_CAST")
+    return f.get(this) as AbstractFieldSupport<*, T>
+}
+
+/**
+ * Sets the value of given component, but only if it is actually possible to do so by the user.
+ * If the component is read-only or disabled, an exception is thrown.
+ *
+ * Modification of this property fires the value change event; the [HasValue.ValueChangeEvent.isFromClient] will
+ * mirror the [fromClient] parameter which defaults to `true` indicating that the event came from the client.
+ * @throws IllegalStateException if the field was not visible, not enabled or was read-only.
+ */
+@JvmOverloads
+public fun <V> HasValue<*, V>._setValue(value: V?, fromClient: Boolean = true) {
+    (this as Component)._expectEditableByUser()
+    val fs = (this as AbstractField<*, V>)._fieldSupport
+    val m = AbstractFieldSupport::class.java.getDeclaredMethod("setValue", Any::class.java, Boolean::class.java, Boolean::class.java)
+    m.isAccessible = true
+    m.invoke(fs, value, false, fromClient)
+}
+
 /**
  * Fires a value change event which "comes from the client".
  *