Undo replaces previous state if we delete an empty text

[vinodgubbala]

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Steps for Reproduction

const quill = render(<Editor />
await userEvent.type(document.querySelector('.ql-editor'), 'foo');

// after a delay
await new Promise(res => setTimeout(res, 2000));
quill.deleteText(2, 0, 'user');
await userEvent.type(document.querySelector('.ql-editor'), 'abc');
expect(document.body).toHaveTextContent('foo'); //but the editor is empty

Expected behavior: To have text content "foo"

Actual behavior: But the text is empty

Platforms: Mac

Version: 2.0.3

In history.ts, we return if the delta is empty.
But the timestamp is still recorded. This makes the next record replace the previous stack.

quill/packages/quill/src/modules/history.ts

Lines 126 to 132 in ebe16ca

	}
	} else {
	this.lastRecorded = timestamp;
	}
	if (undoDelta.length() === 0) return;
	this.stack.undo.push({ delta: undoDelta, range: undoRange });
	// @ts-expect-error Fix me later

Moving this line

quill/packages/quill/src/modules/history.ts

Line 130 in ebe16ca

if (undoDelta.length() === 0) return;

above the if condition should fix it.

quill/packages/quill/src/modules/history.ts

Lines 116 to 118 in ebe16ca

	const timestamp = Date.now();
	if (
	// @ts-expect-error Fix me later