From a38c3963f27ac23616ba04b6c63384d941cd82f0 Mon Sep 17 00:00:00 2001
From: Oliver <oliver.henry.walters@gmail.com>
Date: Fri, 10 Jul 2026 16:54:13 +1000
Subject: [PATCH] [UI] Form fix (#12348)

* Refactor API form fields

- Prevent reconstruction of all fields when single value changes
- Memoize components more intelligently
- Fix enter key callback ref

* memoize other field types too

* More memo

* Prevent duplicate API calls for related model field

* Add aria-label for IconField

* add playwright tests for form field coverage
---
 src/frontend/src/components/forms/ApiForm.tsx |  66 ++++++++--
 .../src/components/forms/DateTimeField.tsx    |   6 +-
 .../components/forms/fields/ApiFormField.tsx  |  27 ++--
 .../components/forms/fields/BooleanField.tsx  |  13 +-
 .../components/forms/fields/ChoiceField.tsx   |  10 +-
 .../src/components/forms/fields/DateField.tsx |   6 +-
 .../forms/fields/DependentField.tsx           |  17 +--
 .../src/components/forms/fields/IconField.tsx |  14 ++-
 .../forms/fields/NestedObjectField.tsx        |   5 +-
 .../components/forms/fields/NumberField.tsx   |  25 ++--
 .../forms/fields/RelatedModelField.tsx        |  15 ++-
 .../components/forms/fields/TableField.tsx    |  38 +-----
 .../src/components/forms/fields/TagsField.tsx |   6 +-
 .../src/components/forms/fields/TextField.tsx |   8 +-
 .../src/components/forms/fields/TreeField.tsx |   6 +-
 src/frontend/src/functions/comparison.tsx     |  55 +++++++++
 .../tests/pages/pui_purchasing.spec.ts        |  20 +++
 src/frontend/tests/pui_forms.spec.ts          | 115 +++++++++++++++++-
 18 files changed, 355 insertions(+), 97 deletions(-)
 create mode 100644 src/frontend/src/functions/comparison.tsx

diff --git a/src/frontend/src/components/forms/ApiForm.tsx b/src/frontend/src/components/forms/ApiForm.tsx
index 1d65b5784f..8d03f9c9b8 100644
--- a/src/frontend/src/components/forms/ApiForm.tsx
+++ b/src/frontend/src/components/forms/ApiForm.tsx
@@ -41,6 +41,7 @@ import type {
   ApiFormProps
 } from '@lib/types/Forms';
 import { useApi } from '../../contexts/ApiContext';
+import { isEquivalent } from '../../functions/comparison';
 import { constructField, extractAvailableFields } from '../../functions/forms';
 import { KeepFormOpenSwitch } from './KeepFormOpenSwitch';
 import { ApiFormField } from './fields/ApiFormField';
@@ -122,15 +123,23 @@ export function OptionsApiForm({
     }
   }, [opened]);
 
+  // Preserve the previous reference for any field whose constructed
+  // definition did not actually change, so unrelated fields don't force a
+  // fields-object replacement (and cascade a re-render to every field)
+  // whenever this recomputes for an unrelated reason (e.g. options data or
+  // the caller's own fields hook re-running with equivalent output)
+  const previousConstructedFieldsRef = useRef<ApiFormFieldSet>({});
+
   const formProps: ApiFormProps = useMemo(() => {
     const _props = { ...props };
 
     if (!_props.fields) return _props;
 
-    _props.fields = { ..._props.fields };
+    const prevFields = previousConstructedFieldsRef.current;
+    const nextFields: ApiFormFieldSet = {};
 
     for (const [k, v] of Object.entries(_props.fields)) {
-      _props.fields[k] = constructField({
+      const constructed = constructField({
         field: v,
         definition: optionsQuery?.data?.[k]
       });
@@ -139,10 +148,17 @@ export function OptionsApiForm({
       const value = _props?.initialData?.[k];
 
       if (value) {
-        _props.fields[k].value = value;
+        constructed.value = value;
       }
+
+      const prev = prevFields[k];
+      nextFields[k] =
+        prev && isEquivalent(prev, constructed) ? prev : constructed;
     }
 
+    previousConstructedFieldsRef.current = nextFields;
+    _props.fields = nextFields;
+
     return _props;
   }, [optionsQuery.data, props]);
 
@@ -314,7 +330,21 @@ export function ApiForm({
       }
     }
 
-    setFields(_fields);
+    // Preserve the previous reference for any field whose definition did not
+    // actually change, so unrelated fields don't re-render just because the
+    // fields hook rebuilt its entire output (e.g. in response to some other
+    // field's onValueChange updating local state elsewhere in that hook)
+    setFields((prevFields) => {
+      const nextFields: ApiFormFieldSet = {};
+
+      for (const k of Object.keys(_fields)) {
+        const prev = prevFields[k];
+        const next = _fields[k];
+        nextFields[k] = prev && isEquivalent(prev, next) ? prev : next;
+      }
+
+      return nextFields;
+    });
   }, [props.fields, props.initialData, defaultValues, initialDataQuery.data]);
 
   // Fetch initial data on form load
@@ -600,6 +630,24 @@ export function ApiForm({
     [props.onFormError]
   );
 
+  // Submit the form when "Enter" is pressed in a field.
+  // Routed through a ref so that the callback identity passed down to every
+  // field stays stable across renders - isValid / isDirty change on every
+  // keystroke anywhere in the form, and a fresh onKeyDown reference here
+  // would force every field (not just the one being edited) to re-render.
+  const submitOnEnterRef = useRef<() => void>(() => {});
+  submitOnEnterRef.current = () => {
+    if (!isLoading && (!props.fetchInitialData || isDirty)) {
+      form.handleSubmit(submitForm, onFormError)();
+    }
+  };
+
+  const onFieldKeyDown = useCallback((value: any) => {
+    if (value === 'Enter') {
+      submitOnEnterRef.current();
+    }
+  }, []);
+
   // Submit the form with Ctrl+Enter (Cmd+Enter on Mac) while it is open.
   // An empty tagsToIgnore list allows the hotkey to fire from within form inputs.
   useInvenTreeHotkeys(
@@ -685,15 +733,7 @@ export function ApiForm({
                           url={url}
                           navigate={navigate}
                           setFields={setFields}
-                          onKeyDown={(value) => {
-                            if (
-                              value == 'Enter' &&
-                              !isLoading &&
-                              (!props.fetchInitialData || isDirty)
-                            ) {
-                              form.handleSubmit(submitForm, onFormError)();
-                            }
-                          }}
+                          onKeyDown={onFieldKeyDown}
                         />
                       );
                     })}
diff --git a/src/frontend/src/components/forms/DateTimeField.tsx b/src/frontend/src/components/forms/DateTimeField.tsx
index 7c888f72af..0854f5c00c 100644
--- a/src/frontend/src/components/forms/DateTimeField.tsx
+++ b/src/frontend/src/components/forms/DateTimeField.tsx
@@ -3,12 +3,12 @@ import { t } from '@lingui/core/macro';
 import { DateTimePicker } from '@mantine/dates';
 import dayjs from 'dayjs';
 import customParseFormat from 'dayjs/plugin/customParseFormat';
-import { useCallback, useId, useMemo } from 'react';
+import { memo, useCallback, useId, useMemo } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 
 dayjs.extend(customParseFormat);
 
-export default function DateTimeField({
+function DateTimeField({
   controller,
   definition
 }: Readonly<{
@@ -73,3 +73,5 @@ export default function DateTimeField({
     />
   );
 }
+
+export default memo(DateTimeField);
diff --git a/src/frontend/src/components/forms/fields/ApiFormField.tsx b/src/frontend/src/components/forms/fields/ApiFormField.tsx
index 1d76affc79..3212c3ed89 100644
--- a/src/frontend/src/components/forms/fields/ApiFormField.tsx
+++ b/src/frontend/src/components/forms/fields/ApiFormField.tsx
@@ -121,6 +121,15 @@ export function ApiFormField({
     [fieldName, definition]
   );
 
+  // Stable wrapper so the identity passed to leaf field components does not
+  // change unless onKeyDown itself changes (onKeyDown may be undefined)
+  const safeOnKeyDown = useCallback(
+    (value: any) => {
+      onKeyDown?.(value);
+    },
+    [onKeyDown]
+  );
+
   // Construct the individual field
   const fieldInstance = useMemo(() => {
     switch (fieldDefinition.field_type) {
@@ -177,9 +186,7 @@ export function ApiFormField({
             controller={controller}
             fieldName={fieldName}
             onChange={onChange}
-            onKeyDown={(value) => {
-              onKeyDown?.(value);
-            }}
+            onKeyDown={safeOnKeyDown}
           />
         );
       case 'password':
@@ -189,9 +196,7 @@ export function ApiFormField({
             controller={controller}
             fieldName={fieldName}
             onChange={onChange}
-            onKeyDown={(value) => {
-              onKeyDown?.(value);
-            }}
+            onKeyDown={safeOnKeyDown}
           />
         );
       case 'icon':
@@ -204,9 +209,7 @@ export function ApiFormField({
             controller={controller}
             definition={reducedDefinition}
             fieldName={fieldName}
-            onChange={(value: boolean) => {
-              onChange(value);
-            }}
+            onChange={onChange}
           />
         );
       case 'date':
@@ -231,9 +234,7 @@ export function ApiFormField({
               fieldDefinition.placeholderWarningCompare ?? undefined
             }
             placeholderWarning={fieldDefinition.placeholderWarning ?? undefined}
-            onChange={(value: any) => {
-              onChange(value);
-            }}
+            onChange={onChange}
           />
         );
       case 'choice':
@@ -311,7 +312,7 @@ export function ApiFormField({
     fieldName,
     fieldDefinition,
     onChange,
-    onKeyDown,
+    safeOnKeyDown,
     reducedDefinition,
     ref,
     setFields,
diff --git a/src/frontend/src/components/forms/fields/BooleanField.tsx b/src/frontend/src/components/forms/fields/BooleanField.tsx
index 033e58cf30..7fc01aa065 100644
--- a/src/frontend/src/components/forms/fields/BooleanField.tsx
+++ b/src/frontend/src/components/forms/fields/BooleanField.tsx
@@ -2,10 +2,10 @@ import { isTrue } from '@lib/functions/Conversion';
 import type { ApiFormFieldType } from '@lib/types/Forms';
 import { Switch } from '@mantine/core';
 import { useId } from '@mantine/hooks';
-import { useEffect, useMemo } from 'react';
+import { memo, useCallback, useEffect, useMemo } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 
-export function BooleanField({
+function BooleanFieldComponent({
   controller,
   definition,
   fieldName,
@@ -37,6 +37,11 @@ export function BooleanField({
     return isTrue(value ?? definition.default ?? false);
   }, [value]);
 
+  const handleChange = useCallback(
+    (event: any) => onChange(event.currentTarget.checked || false),
+    [onChange]
+  );
+
   return (
     <Switch
       {...definition}
@@ -47,7 +52,9 @@ export function BooleanField({
       radius='lg'
       size='sm'
       error={definition.error ?? error?.message}
-      onChange={(event: any) => onChange(event.currentTarget.checked || false)}
+      onChange={handleChange}
     />
   );
 }
+
+export const BooleanField = memo(BooleanFieldComponent);
diff --git a/src/frontend/src/components/forms/fields/ChoiceField.tsx b/src/frontend/src/components/forms/fields/ChoiceField.tsx
index 38258d2d86..e648320dce 100644
--- a/src/frontend/src/components/forms/fields/ChoiceField.tsx
+++ b/src/frontend/src/components/forms/fields/ChoiceField.tsx
@@ -1,13 +1,13 @@
 import type { ApiFormFieldType } from '@lib/types/Forms';
 import { Select } from '@mantine/core';
 import { useId } from '@mantine/hooks';
-import { useCallback, useMemo, useRef } from 'react';
+import { memo, useCallback, useMemo, useRef } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 
 /**
  * Render a 'select' field for selecting from a list of choices
  */
-export function ChoiceField({
+function ChoiceFieldComponent({
   controller,
   definition,
   fieldName
@@ -64,6 +64,8 @@ export function ChoiceField({
     }
   }, [value]);
 
+  const onDropdownOpen = useCallback(() => inputRef?.current?.select(), []);
+
   return (
     <Select
       id={fieldId}
@@ -72,7 +74,7 @@ export function ChoiceField({
       radius='sm'
       {...field}
       ref={inputRef}
-      onDropdownOpen={() => inputRef?.current?.select()}
+      onDropdownOpen={onDropdownOpen}
       onChange={onChange}
       data={choices}
       value={choiceValue}
@@ -88,3 +90,5 @@ export function ChoiceField({
     />
   );
 }
+
+export const ChoiceField = memo(ChoiceFieldComponent);
diff --git a/src/frontend/src/components/forms/fields/DateField.tsx b/src/frontend/src/components/forms/fields/DateField.tsx
index c1fc187d8a..7078cbcbe0 100644
--- a/src/frontend/src/components/forms/fields/DateField.tsx
+++ b/src/frontend/src/components/forms/fields/DateField.tsx
@@ -3,12 +3,12 @@ import { t } from '@lingui/core/macro';
 import { DateInput } from '@mantine/dates';
 import dayjs from 'dayjs';
 import customParseFormat from 'dayjs/plugin/customParseFormat';
-import { useCallback, useId, useMemo } from 'react';
+import { memo, useCallback, useId, useMemo } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 
 dayjs.extend(customParseFormat);
 
-export default function DateField({
+function DateField({
   controller,
   definition
 }: Readonly<{
@@ -76,3 +76,5 @@ export default function DateField({
     />
   );
 }
+
+export default memo(DateField);
diff --git a/src/frontend/src/components/forms/fields/DependentField.tsx b/src/frontend/src/components/forms/fields/DependentField.tsx
index 60fa9497e4..6c4a616c76 100644
--- a/src/frontend/src/components/forms/fields/DependentField.tsx
+++ b/src/frontend/src/components/forms/fields/DependentField.tsx
@@ -1,4 +1,4 @@
-import { useEffect, useMemo } from 'react';
+import { memo, useEffect, useMemo } from 'react';
 import {
   type Control,
   type FieldValues,
@@ -13,7 +13,7 @@ import {
 } from '../../../functions/forms';
 import { ApiFormField } from './ApiFormField';
 
-export function DependentField({
+function DependentFieldComponent({
   control,
   fieldName,
   definition,
@@ -51,14 +51,15 @@ export function DependentField({
         extractAvailableFields(res, 'POST');
 
       // update the fields in the form state with the new fields
+      // (preserve the reference for any field that did not actually change,
+      // so unrelated fields don't re-render on every dependent-field update)
       setFields((prevFields) => {
-        const newFields: Record<string, ReturnType<typeof constructField>> = {};
+        const newFields: ApiFormFieldSet = {};
 
         for (const [k, v] of Object.entries(prevFields)) {
-          newFields[k] = constructField({
-            field: v,
-            definition: fields?.[k]
-          });
+          newFields[k] = fields?.[k]
+            ? constructField({ field: v, definition: fields[k] })
+            : v;
         }
 
         return newFields;
@@ -89,3 +90,5 @@ export function DependentField({
     />
   );
 }
+
+export const DependentField = memo(DependentFieldComponent);
diff --git a/src/frontend/src/components/forms/fields/IconField.tsx b/src/frontend/src/components/forms/fields/IconField.tsx
index 980b508733..cb2a7fc841 100644
--- a/src/frontend/src/components/forms/fields/IconField.tsx
+++ b/src/frontend/src/components/forms/fields/IconField.tsx
@@ -17,7 +17,14 @@ import {
 import { useDebouncedValue, useElementSize } from '@mantine/hooks';
 import { IconX } from '@tabler/icons-react';
 import Fuse from 'fuse.js';
-import { startTransition, useEffect, useMemo, useRef, useState } from 'react';
+import {
+  memo,
+  startTransition,
+  useEffect,
+  useMemo,
+  useRef,
+  useState
+} from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 import { FixedSizeGrid as Grid } from 'react-window';
 
@@ -26,7 +33,7 @@ import { useShallow } from 'zustand/react/shallow';
 import { useIconState } from '../../../states/IconState';
 import { ApiIcon } from '../../items/ApiIcon';
 
-export default function IconField({
+function IconField({
   controller,
   definition
 }: Readonly<{
@@ -53,6 +60,7 @@ export default function IconField({
           description={definition.description}
           required={definition.required}
           error={definition.error ?? error?.message}
+          aria-label={`icon-field-${field.name}`}
           ref={field.ref}
           component='button'
           type='button'
@@ -99,6 +107,8 @@ export default function IconField({
   );
 }
 
+export default memo(IconField);
+
 type RenderIconType = {
   package: string;
   name: string;
diff --git a/src/frontend/src/components/forms/fields/NestedObjectField.tsx b/src/frontend/src/components/forms/fields/NestedObjectField.tsx
index daf3e56752..0e580fae46 100644
--- a/src/frontend/src/components/forms/fields/NestedObjectField.tsx
+++ b/src/frontend/src/components/forms/fields/NestedObjectField.tsx
@@ -1,9 +1,10 @@
 import type { ApiFormFieldSet, ApiFormFieldType } from '@lib/types/Forms';
 import { Accordion, Divider, Stack, Text } from '@mantine/core';
+import { memo } from 'react';
 import type { Control, FieldValues } from 'react-hook-form';
 import { ApiFormField } from './ApiFormField';
 
-export function NestedObjectField({
+function NestedObjectFieldComponent({
   control,
   fieldName,
   definition,
@@ -43,3 +44,5 @@ export function NestedObjectField({
     </Accordion>
   );
 }
+
+export const NestedObjectField = memo(NestedObjectFieldComponent);
diff --git a/src/frontend/src/components/forms/fields/NumberField.tsx b/src/frontend/src/components/forms/fields/NumberField.tsx
index 0369d0935a..3402db445c 100644
--- a/src/frontend/src/components/forms/fields/NumberField.tsx
+++ b/src/frontend/src/components/forms/fields/NumberField.tsx
@@ -1,5 +1,5 @@
 import { NumberInput } from '@mantine/core';
-import { useId, useMemo } from 'react';
+import { memo, useCallback, useId, useMemo } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 import AutoFillRightSection, { AutoFillWarning } from './AutoFillRightSection';
 
@@ -7,7 +7,7 @@ import AutoFillRightSection, { AutoFillWarning } from './AutoFillRightSection';
  * Custom implementation of the mantine <NumberInput> component,
  * used for rendering numerical input fields in forms.
  */
-export default function NumberField({
+function NumberField({
   controller,
   fieldName,
   definition,
@@ -97,6 +97,17 @@ export default function NumberField({
     onChange
   ]);
 
+  const handleChange = useCallback(
+    (value: number | string | null) => {
+      if (value != null && value.toString().trim() === '') {
+        onChange(null);
+      } else {
+        onChange(value);
+      }
+    },
+    [onChange]
+  );
+
   return (
     <NumberInput
       {...definition}
@@ -108,14 +119,10 @@ export default function NumberField({
       value={numericalValue === null ? '' : numericalValue}
       decimalScale={definition.field_type == 'integer' ? 0 : 10}
       step={1}
-      onChange={(value: number | string | null) => {
-        if (value != null && value.toString().trim() === '') {
-          onChange(null);
-        } else {
-          onChange(value);
-        }
-      }}
+      onChange={handleChange}
       rightSection={rightSection}
     />
   );
 }
+
+export default memo(NumberField);
diff --git a/src/frontend/src/components/forms/fields/RelatedModelField.tsx b/src/frontend/src/components/forms/fields/RelatedModelField.tsx
index a744f3f4ac..7b7ac62579 100644
--- a/src/frontend/src/components/forms/fields/RelatedModelField.tsx
+++ b/src/frontend/src/components/forms/fields/RelatedModelField.tsx
@@ -10,6 +10,7 @@ import { useDebouncedValue, useId } from '@mantine/hooks';
 import { useQuery } from '@tanstack/react-query';
 import {
   type ReactNode,
+  memo,
   useCallback,
   useEffect,
   useMemo,
@@ -47,7 +48,7 @@ import { RenderInstance } from '../../render/Instance';
 /**
  * Render a 'select' field for searching the database against a particular model type
  */
-export function RelatedModelField({
+function RelatedModelFieldComponent({
   controller,
   fieldName,
   definition,
@@ -285,6 +286,13 @@ export function RelatedModelField({
     field.value
   ]);
 
+  // Track which id we've already requested (or are currently requesting),
+  // so that if this effect re-fires for an unrelated reason - e.g. a new
+  // `definition.filters`/`definition.api_url` reference - before the
+  // in-flight request for the same id resolves and updates `pk`, it doesn't
+  // issue a duplicate API call for that same id.
+  const requestedIdRef = useRef<number | string | null>(null);
+
   // If an initial value is provided, load from the API
   useEffect(() => {
     // If the value is unchanged, do nothing
@@ -293,8 +301,11 @@ export function RelatedModelField({
     const id = pk || field.value;
 
     if (id !== null && id !== undefined && id !== '') {
+      if (requestedIdRef.current === id) return;
+      requestedIdRef.current = id;
       fetchSingleField(id);
     } else {
+      requestedIdRef.current = null;
       setPk(null);
     }
   }, [
@@ -571,6 +582,8 @@ export function RelatedModelField({
   );
 }
 
+export const RelatedModelField = memo(RelatedModelFieldComponent);
+
 function InlineCreateButton({
   definition,
   modelInfo,
diff --git a/src/frontend/src/components/forms/fields/TableField.tsx b/src/frontend/src/components/forms/fields/TableField.tsx
index 8c4b8ceaa8..5dc69cf903 100644
--- a/src/frontend/src/components/forms/fields/TableField.tsx
+++ b/src/frontend/src/components/forms/fields/TableField.tsx
@@ -26,6 +26,7 @@ import {
 import { AddItemButton } from '@lib/components/AddItemButton';
 import { identifierString } from '@lib/functions/Conversion';
 import type { ApiFormFieldType } from '@lib/types/Forms';
+import { isEquivalent } from '../../../functions/comparison';
 import { InvenTreeIcon } from '../../../functions/icons';
 import { StandaloneField } from '../StandaloneField';
 
@@ -97,42 +98,13 @@ function TableFieldRow({
 }
 
 // Memoize each table field row, so that we don't re-render the entire table when a single row is updated
-function areShallowEqual(previousValue: any, nextValue: any): boolean {
-  if (previousValue === nextValue) {
-    return true;
-  }
-
-  if (!previousValue || !nextValue) {
-    return false;
-  }
-
-  if (typeof previousValue !== 'object' || typeof nextValue !== 'object') {
-    return previousValue === nextValue;
-  }
-
-  const previousKeys = Object.keys(previousValue);
-  const nextKeys = Object.keys(nextValue);
-
-  if (previousKeys.length !== nextKeys.length) {
-    return false;
-  }
-
-  for (const key of previousKeys) {
-    if (previousValue[key] !== nextValue[key]) {
-      return false;
-    }
-  }
-
-  return true;
-}
-
 const MemoizedTableFieldRow = memo(
   TableFieldRow,
   (previousProps, nextProps) => {
     return (
       previousProps.rowId === nextProps.rowId &&
-      areShallowEqual(previousProps.item, nextProps.item) &&
-      areShallowEqual(previousProps.rowErrors, nextProps.rowErrors) &&
+      isEquivalent(previousProps.item, nextProps.item) &&
+      isEquivalent(previousProps.rowErrors, nextProps.rowErrors) &&
       previousProps.modelRenderer === nextProps.modelRenderer &&
       previousProps.changeFn === nextProps.changeFn &&
       previousProps.removeFn === nextProps.removeFn &&
@@ -388,8 +360,8 @@ export const TableField = memo(
     return (
       previousProps.definition === nextProps.definition &&
       previousProps.fieldName === nextProps.fieldName &&
-      areShallowEqual(previousProps.value, nextProps.value) &&
-      areShallowEqual(previousProps.error, nextProps.error) &&
+      isEquivalent(previousProps.value, nextProps.value) &&
+      isEquivalent(previousProps.error, nextProps.error) &&
       previousProps.onChange === nextProps.onChange
     );
   }
diff --git a/src/frontend/src/components/forms/fields/TagsField.tsx b/src/frontend/src/components/forms/fields/TagsField.tsx
index 2777fe4758..667a218f76 100644
--- a/src/frontend/src/components/forms/fields/TagsField.tsx
+++ b/src/frontend/src/components/forms/fields/TagsField.tsx
@@ -1,7 +1,7 @@
 import { TagsInput } from '@mantine/core';
 import { useDebouncedValue } from '@mantine/hooks';
 import { useQuery } from '@tanstack/react-query';
-import { useCallback, useEffect, useMemo, useState } from 'react';
+import { memo, useCallback, useEffect, useMemo, useState } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 
 import { ApiEndpoints } from '@lib/enums/ApiEndpoints';
@@ -9,7 +9,7 @@ import { apiUrl } from '@lib/functions/Api';
 import type { ApiFormFieldType } from '@lib/types/Forms';
 import { api } from '../../../App';
 
-export default function TagsField({
+function TagsField({
   controller,
   definition
 }: Readonly<{
@@ -79,3 +79,5 @@ export default function TagsField({
     />
   );
 }
+
+export default memo(TagsField);
diff --git a/src/frontend/src/components/forms/fields/TextField.tsx b/src/frontend/src/components/forms/fields/TextField.tsx
index 3c43084734..d1b887cba9 100644
--- a/src/frontend/src/components/forms/fields/TextField.tsx
+++ b/src/frontend/src/components/forms/fields/TextField.tsx
@@ -1,5 +1,5 @@
 import { TextInput } from '@mantine/core';
-import { useCallback, useEffect, useId, useMemo, useState } from 'react';
+import { memo, useCallback, useEffect, useId, useMemo, useState } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 import AutoFillRightSection from './AutoFillRightSection';
 
@@ -8,7 +8,7 @@ import AutoFillRightSection from './AutoFillRightSection';
  * used for rendering text input fields in forms.
  * Uses a debounced value to prevent excessive re-renders.
  */
-export default function TextField({
+function TextField({
   controller,
   fieldName,
   definition,
@@ -29,7 +29,7 @@ export default function TextField({
     fieldState: { error }
   } = controller;
 
-  const { value } = useMemo(() => field, [field]);
+  const { value } = field;
 
   const [textValue, setTextValue] = useState<string>(value || '');
 
@@ -91,3 +91,5 @@ export default function TextField({
     />
   );
 }
+
+export default memo(TextField);
diff --git a/src/frontend/src/components/forms/fields/TreeField.tsx b/src/frontend/src/components/forms/fields/TreeField.tsx
index a9a9165cdd..729669d21a 100644
--- a/src/frontend/src/components/forms/fields/TreeField.tsx
+++ b/src/frontend/src/components/forms/fields/TreeField.tsx
@@ -15,7 +15,7 @@ import {
   IconX
 } from '@tabler/icons-react';
 import { useQuery } from '@tanstack/react-query';
-import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
+import { memo, useCallback, useEffect, useMemo, useRef, useState } from 'react';
 import type { FieldValues, UseControllerReturn } from 'react-hook-form';
 import type { NavigateFunction } from 'react-router-dom';
 
@@ -41,7 +41,7 @@ import { ModelHoverCard } from '../../render/ModelHoverCard';
  * endpoint. Supports server-side search, lazy child loading, and (when a model
  * type is provided) barcode scanning and a hover-card navigate link.
  */
-export function TreeField({
+function TreeFieldComponent({
   controller,
   definition,
   fieldName,
@@ -497,3 +497,5 @@ export function TreeField({
     </Input.Wrapper>
   );
 }
+
+export const TreeField = memo(TreeFieldComponent);
diff --git a/src/frontend/src/functions/comparison.tsx b/src/frontend/src/functions/comparison.tsx
new file mode 100644
index 0000000000..a1f6293f42
--- /dev/null
+++ b/src/frontend/src/functions/comparison.tsx
@@ -0,0 +1,55 @@
+/** Generic value-comparison helpers, used to keep memoized props/state stable */
+
+function isReactElement(value: any): boolean {
+  return (
+    value != null &&
+    typeof value === 'object' &&
+    (value.$$typeof === Symbol.for('react.element') ||
+      value.$$typeof === Symbol.for('react.transitional.element'))
+  );
+}
+
+/**
+ * Recursively compare two values for structural equivalence.
+ *
+ * Useful when comparing generated data (e.g. field definitions rebuilt by a
+ * `useMemo`, or table row data) that may get a fresh object/array/JSX-element
+ * reference on every recompute even though nothing meaningful changed -
+ * without this, every consumer downstream would be treated as "changed" and
+ * re-render unnecessarily.
+ *
+ * Functions are deliberately compared by reference only - unlike a JSX icon,
+ * a callback's behavior can depend on values it closes over, so we can't
+ * assume two function instances are interchangeable.
+ */
+export function isEquivalent(a: any, b: any): boolean {
+  if (Object.is(a, b)) {
+    return true;
+  }
+
+  if (isReactElement(a) && isReactElement(b)) {
+    return a.type === b.type && isEquivalent(a.props, b.props);
+  }
+
+  if (typeof a === 'function' || typeof b === 'function') {
+    return false;
+  }
+
+  if (Array.isArray(a) || Array.isArray(b)) {
+    if (!Array.isArray(a) || !Array.isArray(b) || a.length !== b.length) {
+      return false;
+    }
+    return a.every((item, idx) => isEquivalent(item, b[idx]));
+  }
+
+  if (a && b && typeof a === 'object' && typeof b === 'object') {
+    const aKeys = Object.keys(a);
+    const bKeys = Object.keys(b);
+    if (aKeys.length !== bKeys.length) {
+      return false;
+    }
+    return aKeys.every((key) => isEquivalent(a[key], b[key]));
+  }
+
+  return false;
+}
diff --git a/src/frontend/tests/pages/pui_purchasing.spec.ts b/src/frontend/tests/pages/pui_purchasing.spec.ts
index f4a8bd28fb..6a3b1abf98 100644
--- a/src/frontend/tests/pages/pui_purchasing.spec.ts
+++ b/src/frontend/tests/pages/pui_purchasing.spec.ts
@@ -516,6 +516,26 @@ test('Purchase Orders - Receive Items', async ({ browser }) => {
   await page.getByText('Room 101').first().waitFor();
   await page.getByText('Mechanical Lab').first().waitFor();
 
+  // Editing the quantity for one row should not affect any other row
+  // (regression test for per-row TableField memoization)
+  const quantityInputs = page.getByRole('textbox', {
+    name: 'number-field-quantity'
+  });
+
+  // .count() does not auto-wait, so explicitly wait for the second row's
+  // input to be ready before relying on the total count being stable
+  await expect(quantityInputs.nth(1)).toBeVisible();
+
+  const rowCount = await quantityInputs.count();
+  expect(rowCount).toBeGreaterThanOrEqual(2);
+
+  await quantityInputs.nth(0).fill('11');
+  await quantityInputs.nth(1).fill('22');
+  await page.waitForTimeout(250);
+
+  await expect(quantityInputs.nth(0)).toHaveValue('11');
+  await expect(quantityInputs.nth(1)).toHaveValue('22');
+
   await page.getByRole('button', { name: 'Cancel' }).click();
 
   // Let's actually receive an item (with custom values)
diff --git a/src/frontend/tests/pui_forms.spec.ts b/src/frontend/tests/pui_forms.spec.ts
index 692b26351c..0d9204542c 100644
--- a/src/frontend/tests/pui_forms.spec.ts
+++ b/src/frontend/tests/pui_forms.spec.ts
@@ -2,7 +2,7 @@ import { createApi } from './api';
 /** Unit tests for form validation, rendering, etc */
 import { expect, test } from './baseFixtures';
 import { stevenuser } from './defaults';
-import { navigate, openDetailAction } from './helpers';
+import { clickOnRowMenu, loadTab, navigate, openDetailAction } from './helpers';
 import { doCachedLogin } from './login';
 
 // Test hover form action in related fields
@@ -202,3 +202,116 @@ test('Forms - Keep form open option', async ({ browser }) => {
   await page.getByText('Item Created').waitFor();
   await expect(page.getByRole('dialog')).toBeHidden();
 });
+
+test('Forms - DateTime Field', async ({ browser }) => {
+  // The "started_datetime" / "finished_datetime" test-result fields are only
+  // shown when the "TEST_STATION_DATA" global setting is enabled
+  const api = await createApi({});
+  const settingUrl = 'settings/global/TEST_STATION_DATA/';
+
+  const enableResponse = await api.patch(settingUrl, {
+    data: { value: 'true' }
+  });
+  expect(enableResponse.status()).toBe(200);
+
+  const page = await doCachedLogin(browser, {
+    user: stevenuser,
+    url: 'stock/item/1194/test_results'
+  });
+  await page.waitForURL('**/web/stock/**');
+  await loadTab(page, 'Test Results');
+
+  const cell = page.getByText('395c6d5586e5fb656901d047be27e1f7');
+  await clickOnRowMenu(cell);
+  await page.getByRole('menuitem', { name: 'Edit' }).click();
+
+  // Set a value via the Mantine DateTimePicker popup - a button which opens a
+  // calendar (for the date) plus separate hour/minute/second spinbuttons
+  const setDateTime = async (
+    fieldLabel: string,
+    day: string,
+    hour: string,
+    minute: string
+  ) => {
+    const field = page.getByLabel(fieldLabel);
+    await expect(field).toBeVisible();
+    await field.click();
+    await page.getByRole('button', { name: day }).click();
+
+    const spinbuttons = page.getByRole('spinbutton');
+    await spinbuttons.nth(0).fill(hour);
+    await spinbuttons.nth(1).fill(minute);
+    await spinbuttons.nth(2).fill('00');
+
+    await page.keyboard.press('Escape');
+  };
+
+  await setDateTime(
+    'date-time-field-started_datetime',
+    '10 March 2024',
+    '10',
+    '30'
+  );
+  await setDateTime(
+    'date-time-field-finished_datetime',
+    '11 March 2024',
+    '11',
+    '45'
+  );
+
+  await expect(page.getByLabel('date-time-field-started_datetime')).toHaveText(
+    '2024-03-10 10:30:00'
+  );
+  await expect(page.getByLabel('date-time-field-finished_datetime')).toHaveText(
+    '2024-03-11 11:45:00'
+  );
+
+  await page.getByRole('button', { name: 'Submit' }).click();
+  await page.getByText('Test result updated').waitFor();
+
+  // Restore the global setting to its default value
+  const disableResponse = await api.patch(settingUrl, {
+    data: { value: 'false' }
+  });
+  expect(disableResponse.status()).toBe(200);
+});
+
+// Test the "nested object" field type, via the "Initial Supplier" section
+// of the "Create Part" form
+test('Forms - Nested Object Field', async ({ browser }) => {
+  const page = await doCachedLogin(browser, {
+    user: stevenuser,
+    url: 'part/category/index/parts'
+  });
+  await page.waitForURL('**/part/category/index/**');
+
+  await page.getByRole('button', { name: 'action-menu-add-parts' }).click();
+  await page
+    .getByRole('menuitem', { name: 'action-menu-add-parts-create-part' })
+    .click();
+
+  // Generate a unique part name
+  const partName = `Test Part ${new Date().getTime()}`;
+  await page.getByLabel('text-field-name', { exact: true }).fill(partName);
+
+  // The "Initial Supplier" nested-object field should be visible and expanded by default
+  await page.getByText('Supplier Information').waitFor();
+
+  const supplierField = page.getByLabel(
+    'related-field-initial_supplier.supplier'
+  );
+  await expect(supplierField).toBeVisible();
+  await supplierField.fill('Mouser');
+  await page.getByText('Mouser Electronics').first().click();
+
+  const skuValue = `SKU-${new Date().getTime()}`;
+  await page
+    .getByLabel('text-field-initial_supplier.sku', { exact: true })
+    .fill(skuValue);
+
+  await page.getByRole('button', { name: 'Submit' }).click();
+  await page.getByText('Item Created').waitFor();
+
+  // Confirm the part was created with the expected name
+  await page.getByText(partName).first().waitFor();
+});