feat: [UIE-10051] - IAM Delegation: allow sending an empty array (linode#13300)

* feat: [UIE-10051] - IAM Delegation: allow sending an empty array

* Added changeset: IAM DElegation: remove restriction to update user delegation with empty array, update the delegations after reopening a drawer

* small drawer refactor

---------

Co-authored-by: Alban Bailly <abailly@akamai.com>

Author: aaleksee-akamai

packages/manager/.changeset/pr-13300-fixed-1768996885991.md

@@ -0,0 +1,5 @@
+---
+"@linode/manager": Fixed
+---
+
+IAM DElegation: remove restriction to update user delegation with empty array, update the delegations after reopening a drawer ([#13300](https://github.com/linode/manager/pull/13300))

packages/manager/src/features/IAM/Delegations/UpdateDelegationForm.tsx

@@ -0,0 +1,161 @@
+import { useUpdateChildAccountDelegatesQuery } from '@linode/queries';
+import { ActionsPanel, Autocomplete, Notice, Typography } from '@linode/ui';
+import { useTheme } from '@mui/material';
+import { enqueueSnackbar } from 'notistack';
+import * as React from 'react';
+import { Controller, FormProvider, useForm } from 'react-hook-form';
+
+import { usePermissions } from '../hooks/usePermissions';
+import { INTERNAL_ERROR_NO_CHANGES_SAVED } from '../Shared/constants';
+import { getPlaceholder } from '../Shared/Entities/utils';
+
+import type { ChildAccount, ChildAccountWithDelegates } from '@linode/api-v4';
+
+interface UpdateDelegationsFormValues {
+  users: UserOption[];
+}
+
+interface UserOption {
+  label: string;
+  value: string;
+}
+
+interface DelegationsFormProps {
+  delegation: ChildAccount | ChildAccountWithDelegates;
+  formattedCurrentUsers: UserOption[];
+  isLoading: boolean;
+  onClose: () => void;
+  userOptions: UserOption[];
+}
+export const UpdateDelegationForm = ({
+  delegation,
+  formattedCurrentUsers,
+  isLoading,
+  onClose,
+  userOptions,
+}: DelegationsFormProps) => {
+  const theme = useTheme();
+
+  const { data: permissions } = usePermissions('account', [
+    'update_delegate_users',
+  ]);
+
+  const { mutateAsync: updateDelegates } =
+    useUpdateChildAccountDelegatesQuery();
+
+  const form = useForm<UpdateDelegationsFormValues>({
+    defaultValues: {
+      users: formattedCurrentUsers,
+    },
+  });
+
+  const {
+    control,
+    formState: { errors, isSubmitting },
+    handleSubmit,
+    reset,
+    setError,
+  } = form;
+
+  const onSubmit = async (values: UpdateDelegationsFormValues) => {
+    const usersList = values.users.map((user) => user.value);
+
+    try {
+      await updateDelegates({
+        euuid: delegation.euuid,
+        users: usersList,
+      });
+      enqueueSnackbar(`Delegation updated`, { variant: 'success' });
+      handleClose();
+    } catch (errors) {
+      for (const error of errors) {
+        setError('root', {
+          message: error.reason ?? INTERNAL_ERROR_NO_CHANGES_SAVED,
+        });
+      }
+    }
+  };
+
+  const handleClose = () => {
+    reset();
+    onClose();
+  };
+
+  return (
+    <>
+      {errors.root?.message && (
+        <Notice text={errors.root?.message} variant="error" />
+      )}
+      <FormProvider {...form}>
+        <form onSubmit={handleSubmit(onSubmit)}>
+          <Typography sx={{ marginBottom: theme.tokens.spacing.S16 }}>
+            Add or remove users who should have access to the child account.
+            Users removed from this list will lose the role assignment on the
+            child account and they won&apos;t be visible in the user list on the
+            child account.
+          </Typography>
+
+          <Typography
+            sx={{
+              marginBottom: theme.tokens.spacing.S8,
+              overflow: 'hidden',
+              textOverflow: 'ellipsis',
+              whiteSpace: 'nowrap',
+            }}
+          >
+            Update delegation for <strong>{delegation.company}:</strong>
+          </Typography>
+
+          <Controller
+            control={control}
+            name="users"
+            render={({ field, fieldState }) => (
+              <Autocomplete
+                data-testid="delegates-autocomplete"
+                errorText={fieldState.error?.message}
+                isOptionEqualToValue={(option, value) =>
+                  option.value === value.value
+                }
+                label={'Delegate Users'}
+                loading={isLoading}
+                multiple
+                noMarginTop
+                onChange={(_, newValue) => {
+                  field.onChange(newValue || []);
+                }}
+                options={userOptions}
+                placeholder={getPlaceholder(
+                  'delegates',
+                  field.value.length,
+                  userOptions.length
+                )}
+                textFieldProps={{
+                  hideLabel: true,
+                }}
+                value={field.value}
+              />
+            )}
+          />
+
+          <ActionsPanel
+            primaryButtonProps={{
+              'data-testid': 'submit',
+              label: 'Update',
+              loading: isSubmitting,
+              type: 'submit',
+              disabled: !permissions?.update_delegate_users,
+              tooltipText: !permissions?.update_delegate_users
+                ? 'You do not have permission to update delegations.'
+                : undefined,
+            }}
+            secondaryButtonProps={{
+              'data-testid': 'cancel',
+              label: 'Cancel',
+              onClick: handleClose,
+            }}
+          />
+        </form>
+      </FormProvider>
+    </>
+  );
+};

packages/manager/src/features/IAM/Delegations/UpdateDelegationsDrawer.test.tsx

@@ -5,7 +5,6 @@ import { vi } from 'vitest';
 
 import { mockMatchMedia, renderWithTheme } from 'src/utilities/testHelpers';
 
-import { DELEGATION_VALIDATION_ERROR } from '../Shared/constants';
 import { UpdateDelegationsDrawer } from './UpdateDelegationsDrawer';
 
 import type { ChildAccountWithDelegates, User } from '@linode/api-v4';
@@ -118,27 +117,32 @@ describe('UpdateDelegationsDrawer', () => {
     });
   });
 
-  it('should show error when no users are selected', async () => {
-    const emptyDelegation = {
-      ...mockChildAccountWithDelegates,
-      users: [],
-    };
+  it('allows sending an empty payload', async () => {
+    renderWithTheme(<UpdateDelegationsDrawer {...defaultProps} />);
+
+    const user = userEvent.setup();
+
+    // Open the autocomplete and deselect the preselected user (user1)
+    const autocompleteInput = screen.getByRole('combobox');
+    await user.click(autocompleteInput);
+
+    await waitFor(() => {
+      // Ensure options are rendered
+      expect(screen.getByRole('option', { name: 'user1' })).toBeInTheDocument();
+    });
 
-    renderWithTheme(
-      <UpdateDelegationsDrawer
-        delegation={emptyDelegation}
-        onClose={vi.fn()}
-        open={true}
-      />
-    );
+    const user1Option = screen.getByRole('option', { name: 'user1' });
+    await user.click(user1Option); // toggles off the selected user
 
-    // Try to submit without selecting any users
-    const submitButton = screen.getByRole('button', { name: 'Update' });
-    await userEvent.click(submitButton);
+    // Submit with no users selected
+    const submitButton = screen.getByRole('button', { name: /update/i });
+    await user.click(submitButton);
 
     await waitFor(() => {
-      const errorElement = screen.getByText(DELEGATION_VALIDATION_ERROR);
-      expect(errorElement).toBeVisible();
+      expect(mocks.mockMutateAsync).toHaveBeenCalledWith({
+        euuid: mockChildAccountWithDelegates.euuid,
+        users: [],
+      });
     });
   });
 });