Follow the test method descriped in Issue #16651 as the test case involved a core block.

I have created a block with both TextControl and RichText.

When I select the RichText I get the toolbar but the toolbar does not disappear when the TextControl is selected. I have tested this with Gutenberg 3.1

Here is a screenshot of the block with the TextControl and RichText.

I have created a example plugin where this can be tested: grappler-block.zip

The code it the edit is

<div className={ className }>
	<TextControl
		label={ __( 'TextControl' ) }
		value={ attributes.textControl || '' }
		type="text"
		onChange={ ( newValue ) => {
			setAttributes( { textControl: newValue } );
		} }
	/>

	<RichText
		multiline="li"
		tagName="ul"
		formattingControls={ [ 'bold', 'link' ] }
		value={ attributes.richText }
		placeholder={ __( 'RichText' ) }
		onChange={ ( content ) => setAttributes( { richText: content } ) }
	/>
</div>

This was previously working with a custom onFocus.

Related PRs #7029 & #6871