fix(forms): clear hidden listener fields instead of applying default value

.github/workflows/deploy-to-feature-environment.yml

@@ -294,25 +294,45 @@ jobs:
             });
 
             console.log(result);
-            await new Promise(resolve => setTimeout(resolve, 10000));
 
-            const runs = await github.rest.actions.listWorkflowRunsForRepo({
-              owner: 'opencrvs',
-              repo: 'e2e',
-              event: 'repository_dispatch',
-              per_page: 1
-            });
+            // Record the time just before dispatching so we can ignore any
+            // pre-existing runs when polling below.
+            const dispatchedAt = new Date();
 
-            if (runs.data.workflow_runs.length > 0) {
-              const runId = runs.data.workflow_runs[0].id;
-              console.log(`Captured runId: ${runId}`);
+            // GitHub Actions can take variable time to register a newly dispatched
+            // run in the API. Poll every 5 seconds for up to 60 seconds, and only
+            // accept a run whose created_at is >= dispatchedAt to avoid picking up
+            // a stale run from a previous dispatch (e.g. one triggered by farajaland).
+            let runId;
+            for (let i = 0; i < 12; i++) {
+              await new Promise(resolve => setTimeout(resolve, 5000));
 
-              // Set the runId as an output
-              core.setOutput('run_id', runId);
-            } else {
-              throw new Error('No workflow run found.');
+              const runs = await github.rest.actions.listWorkflowRunsForRepo({
+                owner: 'opencrvs',
+                repo: 'e2e',
+                event: 'repository_dispatch',
+                per_page: 5
+              });
+
+              const newRun = runs.data.workflow_runs.find(
+                r => new Date(r.created_at) >= dispatchedAt
+              );
+
+              if (newRun) {
+                runId = newRun.id;
+                console.log(`Captured runId: ${runId} (created at ${newRun.created_at})`);
+                break;
+              }
+
+              console.log(`Run not visible yet, retrying... (attempt ${i + 1}/12)`);
             }
 
+            if (!runId) {
+              throw new Error('No workflow run found after 60 seconds.');
+            }
+
+            core.setOutput('run_id', runId);
+
       - name: Print link to E2E workflow run
         id: print-links
         run: |

packages/client/src/v2-events/components/forms/FormFieldGenerator/FormFieldGenerator.interaction.stories.tsx

@@ -1,3 +1,4 @@
+/* eslint-disable max-lines */
 /*
  * This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
@@ -530,6 +531,100 @@ export const AlternateVariantDefaultIsUsed: Story = {
   }
 }
 
+const hiddenListenerFields = [
+  {
+    id: 'form.type',
+    type: FieldType.SELECT,
+    required: true,
+    label: generateTranslationConfig('place type'),
+    options: [
+      {
+        label: generateTranslationConfig('Private home'),
+        value: 'PRIVATE_HOME'
+      },
+      {
+        label: generateTranslationConfig('Health facility'),
+        value: 'HEALTH_FACILITY'
+      }
+    ]
+  },
+  {
+    id: 'form.address',
+    type: FieldType.TEXT,
+    label: generateTranslationConfig('address'),
+    defaultValue: 'district-123',
+    parent: field('form.type'),
+    conditionals: [
+      {
+        type: ConditionalType.SHOW,
+        conditional: field('form.type').isEqualTo('PRIVATE_HOME')
+      }
+    ]
+  },
+  {
+    id: 'form.derivedId',
+    type: FieldType.TEXT,
+    label: generateTranslationConfig('derived id'),
+    parent: field('form.type'),
+    value: field('form.address')
+  }
+] satisfies FieldConfig[]
+
+/**
+ * Regression test for the bug where changing a parent field to a value that hides a listener
+ * field would cause the listener field's defaultValue to be applied to the hidden field,
+ * which would then propagate to aggregator fields via their `value` reference.
+ *
+ * Fix: hidden listener fields are cleared to `null` instead of having `defaultValue` applied.
+ */
+export const HiddenListenerDefaultNotPropagated: Story = {
+  name: 'Parent change clears hidden listener field instead of applying its default value',
+  parameters: {
+    layout: 'centered',
+    chromatic: { disableSnapshot: true }
+  },
+  render: function Component(args) {
+    return (
+      <StyledFormFieldGenerator
+        {...args}
+        fields={hiddenListenerFields}
+        formValues={{ 'form.type': 'PRIVATE_HOME' }}
+        id="my-form"
+      />
+    )
+  },
+  play: async ({ canvasElement, step }) => {
+    const canvas = within(canvasElement)
+
+    await step(
+      'Renders with address field visible and its default value applied',
+      async () => {
+        await expect(
+          await canvas.findByTestId('text__form____address')
+        ).toHaveValue('district-123')
+      }
+    )
+
+    await step(
+      'Changes type to Health facility, hiding the address field',
+      async () => {
+        await userEvent.click(await canvas.findByText('Private home'))
+        await userEvent.click(await canvas.findByText('Health facility'))
+      }
+    )
+
+    await step(
+      'Address field is hidden and derived id is cleared — not the hidden default',
+      async () => {
+        await expect(canvas.queryByText('address')).not.toBeInTheDocument()
+        await expect(canvas.getByTestId('text__form____derivedId')).toHaveValue(
+          ''
+        )
+      }
+    )
+  }
+}
+
 export const CustomRequiredValidationMessage: Story = {
   name: 'Custom required validation message',
   parameters: {

packages/client/src/v2-events/components/forms/FormFieldGenerator/FormSectionComponent.tsx

@@ -37,7 +37,10 @@ import {
 import { useOnlineStatus } from '@client/utils'
 import { useDefaultValue } from '@client/v2-events/hooks/useDefaultValue'
 import { useEventFormData } from '@client/v2-events/features/events/useEventFormData'
-import { makeFormikFieldIdsOpenCRVSCompatible, resolveSyncedFieldValue } from './utils'
+import {
+  makeFormikFieldIdsOpenCRVSCompatible,
+  resolveSyncedFieldValue
+} from './utils'
 import { FormItem, GeneratedInputField } from './GeneratedInputField'
 
 type AllProps = {
@@ -206,7 +209,9 @@ export function FormSectionComponent({
   const getDefaultValue = useDefaultValue()
   const { cacheHiddenFieldValue, popHiddenFieldValue } = useEventFormData()
 
-  const fullFormFields = eventConfig ? findAllFields(eventConfig).concat(pageFields) : pageFields
+  const fullFormFields = eventConfig
+    ? findAllFields(eventConfig).concat(pageFields)
+    : pageFields
   const listenerFieldsByParentId = getParentsOfListenerFields(fullFormFields)
 
   /** Sets the value for fields that listen to another field via `parent` and `value` properties */
@@ -219,18 +224,42 @@ export function FormSectionComponent({
       makeFormFieldIdFormikCompatible
     )
 
-    const firstNonFalsyValue = resolveSyncedFieldValue(listenerField, (syncRef) =>
-      get(
-        fieldValues,
-        flattenFieldReference(syncRef).map(makeFormFieldIdFormikCompatible)
-      )
+    const firstNonFalsyValue = resolveSyncedFieldValue(
+      listenerField,
+      (syncRef) =>
+        get(
+          fieldValues,
+          flattenFieldReference(syncRef).map(makeFormFieldIdFormikCompatible)
+        )
     )
 
     if (firstNonFalsyValue) {
       set(fieldValues, formikCompatibleListenerFieldPath, firstNonFalsyValue)
       return
     }
 
+    const formContext = {
+      ...fullForm,
+      ...makeFormikFieldIdsOpenCRVSCompatible(fieldValues)
+    }
+
+    // Hidden listener fields are cleared to undefined so their stale values
+    // don't leak into other fields that read from them (e.g. via `value` refs).
+    // We return early to skip applying the defaultValue, which would otherwise
+    // pollute the form state for fields that aren't currently relevant.
+
+    // Must be undefined, never null:
+    // null has a specific semantic in the declaration payload — it signals an
+    // intentional field removal and is preserved by getCleanedDeclarationDiff
+    // (via omitHiddenPaginatedFields with retainNullValues=true). Sending null
+    // for fields that were never part of the current action (e.g. correction
+    // form fields appearing in a declare payload) corrupts the event state.
+    // undefined is omitted from JSON serialisation and is therefore safe.
+    if (!isFieldVisible(listenerField, formContext, validatorContext)) {
+      set(fieldValues, formikCompatibleListenerFieldPath, undefined)
+      return
+    }
+
     const defaultValue = getDefaultValue(listenerField)
 
     set(fieldValues, formikCompatibleListenerFieldPath, defaultValue)