Introduce SourceContext

packages/ra-core/src/form/useInput.ts

@@ -45,6 +45,16 @@ export const useInput = <ValueType = any>(
     const formGroups = useFormGroups();
     const record = useRecordContext();
 
+    if (
+        !source &&
+        props.label == null &&
+        process.env.NODE_ENV === 'development'
+    ) {
+        console.warn(
+            'If your input source is empty, you must provide a label prop.'
+        );
+    }
+
     useEffect(() => {
         if (!formGroups || formGroupName == null) {
             return;

packages/ra-core/src/i18n/TestTranslationProvider.tsx

@@ -2,28 +2,35 @@ import * as React from 'react';
 import lodashGet from 'lodash/get';
 
 import { I18nContextProvider } from './I18nContextProvider';
+import { I18nProvider } from '../types';
 
 export const TestTranslationProvider = ({
     translate,
     messages,
     children,
 }: any) => (
-    <I18nContextProvider
-        value={{
-            translate: messages
-                ? (key: string, options?: any) => {
-                      const message = lodashGet(messages, key);
-                      return message
-                          ? typeof message === 'function'
-                              ? message(options)
-                              : message
-                          : options?._ || key;
-                  }
-                : translate,
-            changeLocale: () => Promise.resolve(),
-            getLocale: () => 'en',
-        }}
-    >
+    <I18nContextProvider value={testI18nProvider({ translate, messages })}>
         {children}
     </I18nContextProvider>
 );
+
+export const testI18nProvider = ({
+    translate,
+    messages,
+}: {
+    translate?: I18nProvider['translate'];
+    messages?: Record<string, string | ((options?: any) => string)>;
+}): I18nProvider => ({
+    translate: messages
+        ? (key, options) => {
+              const message = lodashGet(messages, key);
+              return message
+                  ? typeof message === 'function'
+                      ? message(options)
+                      : message
+                  : options?._ || key;
+          }
+        : translate,
+    changeLocale: () => Promise.resolve(),
+    getLocale: () => 'en',
+});

packages/ra-ui-materialui/src/input/ArrayInput/ArrayInput.stories.tsx

@@ -1,6 +1,6 @@
 import * as React from 'react';
 import { Admin } from 'react-admin';
-import { required, Resource } from 'ra-core';
+import { required, Resource, testI18nProvider } from 'ra-core';
 import { createMemoryHistory } from 'history';
 import { InputAdornment } from '@mui/material';
 
@@ -167,6 +167,47 @@ export const Scalar = () => (
     </Admin>
 );
 
+export const ScalarI18n = () => (
+    <Admin
+        dataProvider={dataProvider}
+        history={history}
+        i18nProvider={testI18nProvider({
+            messages: {
+                resources: {
+                    books: {
+                        fields: {
+                            tags: 'Some tags',
+                        },
+                    },
+                },
+            },
+        })}
+    >
+        <Resource
+            name="books"
+            edit={() => (
+                <Edit
+                    mutationMode="pessimistic"
+                    mutationOptions={{
+                        onSuccess: data => {
+                            console.log(data);
+                        },
+                    }}
+                >
+                    <SimpleForm>
+                        <TextInput source="title" />
+                        <ArrayInput source="tags" fullWidth>
+                            <SimpleFormIterator disableReordering>
+                                <TextInput source="" helperText={false} />
+                            </SimpleFormIterator>
+                        </ArrayInput>
+                    </SimpleForm>
+                </Edit>
+            )}
+        />
+    </Admin>
+);
+
 const order = {
     id: 1,
     date: '2022-08-30',

packages/ra-ui-materialui/src/input/ArrayInput/SimpleFormIteratorItem.tsx

@@ -87,10 +87,12 @@ export const SimpleFormIteratorItem = React.forwardRef(
                     source ? `${member}.${source}` : member,
                 getLabel: (source: string) => {
                     // remove digits, e.g. 'book.authors.2.categories.3.identifier.name' => 'book.authors.categories.identifier.name'
-                    const itemSource = `${member.replace(
-                        /\.\d+/g,
-                        ''
-                    )}.${source}`;
+                    const sanitizedMember = member.replace(/\.\d+/g, '');
+                    // source may be empty for scalar values arrays
+                    const itemSource = source
+                        ? `${sanitizedMember}.${source}`
+                        : sanitizedMember;
+
                     return parentSourceContext
                         ? parentSourceContext.getLabel(itemSource)
                         : getResourceFieldLabelKey(resource, itemSource);