Add emptyText prop to SelectInput

docs/Inputs.md

@@ -174,7 +174,7 @@ By default the component matches choices with the current input searchText: if i
 
 If you want to limit the initial choices shown to the current value only, you can set the `limitChoicesToValue` prop.
 
-When dealing with a large amount of `choices` you may need to limit the number of suggestions that are rendered in order to maintain usable performance. The `shouldRenderSuggestions` is an optional prop that allows you to set conditions on when to render suggestions. An easy way to improve performance would be to skip rendering until the user has entered 2 or 3 characters in the search box. This lowers the result set significantly, and might be all you need (depending on your data set). 
+When dealing with a large amount of `choices` you may need to limit the number of suggestions that are rendered in order to maintain usable performance. The `shouldRenderSuggestions` is an optional prop that allows you to set conditions on when to render suggestions. An easy way to improve performance would be to skip rendering until the user has entered 2 or 3 characters in the search box. This lowers the result set significantly, and might be all you need (depending on your data set).
 Ex. `<AutocompleteInput shouldRenderSuggestions={(val) => { return val.trim().length > 2 }} />` would not render any suggestions until the 3rd character was entered. This prop is passed to the underlying `react-autosuggest` component and is documented [here](https://github.com/moroshko/react-autosuggest#should-render-suggestions-prop).
 
 `<AutocompleteInput>` renders a material-ui `<TextField>` component. Use the `options` attribute to override any of the `<TextField>` attributes:
@@ -289,7 +289,7 @@ By default the component matches choices with the current input searchText. For
 
 If you want to limit the initial choices shown to the current value only, you can set the `limitChoicesToValue` prop.
 
-When dealing with a large amount of `choices` you may need to limit the number of suggestions that are rendered in order to maintain usable performance. The `shouldRenderSuggestions` is an optional prop that allows you to set conditions on when to render suggestions. An easy way to improve performance would be to skip rendering until the user has entered 2 or 3 characters in the search box. This lowers the result set significantly, and might be all you need (depending on your data set). 
+When dealing with a large amount of `choices` you may need to limit the number of suggestions that are rendered in order to maintain usable performance. The `shouldRenderSuggestions` is an optional prop that allows you to set conditions on when to render suggestions. An easy way to improve performance would be to skip rendering until the user has entered 2 or 3 characters in the search box. This lowers the result set significantly, and might be all you need (depending on your data set).
 Ex. `<AutocompleteArrayInput shouldRenderSuggestions={(val) => { return val.trim().length > 2 }} />` would not render any suggestions until the 3rd character was entered. This prop is passed to the underlying `react-autosuggest` component and is documented [here](https://github.com/moroshko/react-autosuggest#should-render-suggestions-prop).
 
 Lastly, `<AutocompleteArrayInput>` renders a [material-ui-chip-input](https://github.com/TeamWertarbyte/material-ui-chip-input) component. Use the `options` attribute to override any of the `<ChipInput>` attributes:
@@ -1008,8 +1008,7 @@ const FullNameField = ({ record }) => <span>{record.first_name} {record.last_nam
 <SelectInput source="gender" choices={choices} optionText={<FullNameField />}/>
 ```
 
-Enabling the `allowEmpty` props adds an empty choice (with a default `null` value, which you can overwrite with the `emptyValue` prop) on top of the options, and makes the value nullable:
-
+Enabling the `allowEmpty` props adds an empty choice (with a default `null` value, which you can overwrite with the `emptyValue` prop) on top of the options, and makes the value nullable. You can furthermore customize the `MenuItem` for the empty choice by using the `emptyText` prop, which can receive either a string or a React Element, which doesn't receive any props.
 ```jsx
 <SelectInput source="category" allowEmpty emptyValue="" choices={[
     { id: 'programming', name: 'Programming' },
@@ -1063,7 +1062,7 @@ You can make the `SelectInput` component resettable using the `resettable` prop.
 
 ![resettable SelectInput](./img/resettable-select-input.png)
 
-You can set disabled values by setting the `disabled` property of one item: 
+You can set disabled values by setting the `disabled` property of one item:
 
 ```jsx
 const choices = [
@@ -1074,7 +1073,7 @@ const choices = [
 <SelectInput source="author_id" choices={choices} optionText="full_name" optionValue="_id" />
 ```
 
-You can use a custom field name by setting `disableValue` prop: 
+You can use a custom field name by setting `disableValue` prop:
 
 ```jsx
 const choices = [

packages/ra-ui-materialui/src/input/SelectInput.js

@@ -137,6 +137,7 @@ export const SelectInput = ({
     classes,
     className,
     disableValue,
+    emptyText,
     emptyValue,
     helperText,
     input,
@@ -176,6 +177,15 @@ export const SelectInput = ({
         [input, setValue]
     );
 
+    const renderEmptyItemOption = useCallback(
+        emptyText => {
+            return React.isValidElement(emptyText)
+                ? React.cloneElement(emptyText)
+                : translate(emptyText, { _: emptyText });
+        },
+        [emptyText, translate]
+    );
+
     const renderMenuItemOption = useCallback(
         choice => {
             if (React.isValidElement(optionText)) {
@@ -231,7 +241,11 @@ export const SelectInput = ({
             {...sanitizeRestProps(rest)}
             onChange={handleChange}
         >
-            {allowEmpty ? <MenuItem value={emptyValue} key="null" /> : null}
+            {allowEmpty ? (
+                <MenuItem value={emptyValue} key="null">
+                    {renderEmptyItemOption(emptyText)}
+                </MenuItem>
+            ) : null}
             {choices.map(choice => (
                 <MenuItem
                     key={get(choice, optionValue)}
@@ -247,6 +261,7 @@ export const SelectInput = ({
 
 SelectInput.propTypes = {
     allowEmpty: PropTypes.bool.isRequired,
+    emptyText: PropTypes.oneOfType([PropTypes.string, PropTypes.element]),
     emptyValue: PropTypes.any,
     choices: PropTypes.arrayOf(PropTypes.object),
     classes: PropTypes.object,
@@ -271,6 +286,7 @@ SelectInput.propTypes = {
 
 SelectInput.defaultProps = {
     allowEmpty: false,
+    emptyText: '',
     emptyValue: '',
     classes: {},
     choices: [],

packages/ra-ui-materialui/src/input/SelectInput.spec.js

@@ -117,6 +117,50 @@ describe('<SelectInput />', () => {
         assert.equal(options[0].getAttribute('data-value'), emptyValue);
     });
 
+    it('should add an empty menu with proper text when emptyText is a string', () => {
+        const emptyText = 'Default';
+
+        const { getByRole, getByText, queryAllByRole } = render(
+            <SelectInput
+                allowEmpty
+                emptyText={emptyText}
+                {...defaultProps}
+                choices={[]}
+            />
+        );
+        const EmptyMenuElement = getByRole('button');
+        fireEvent.click(EmptyMenuElement);
+
+        const options = queryAllByRole('option');
+        assert.equal(options.length, 1);
+
+        assert.ok(getByText('Default'));
+    });
+
+    it('should add an empty menu with proper text when emptyText is a React element', () => {
+        const emptyText = (
+            <div>
+                <em>Empty choice</em>
+            </div>
+        );
+
+        const { getByRole, getByText, queryAllByRole } = render(
+            <SelectInput
+                allowEmpty
+                emptyText={emptyText}
+                {...defaultProps}
+                choices={[]}
+            />
+        );
+        const EmptyMenuElement = getByRole('button');
+        fireEvent.click(EmptyMenuElement);
+
+        const options = queryAllByRole('option');
+        assert.equal(options.length, 1);
+
+        assert.ok(getByText('Empty choice'));
+    });
+
     it('should not add a falsy (null or false) element when allowEmpty is false', () => {
         const { getByRole, queryAllByRole } = render(
             <SelectInput