Fix Enterprise URL Entry Box

[coocoo1112]

Summary

Fixes a bug where text typed into the "Enterprise or AE address" TextBox on the GitHub Enterprise sign-in page appears reversed (e.g. typing "https" displays "sptth").

Root Cause

This bug is caused by an interaction between the IME composition handling added in da0f1a10 ("Handle IME composition in text input components") and TextBox consumers that don't pass a value prop.

The IME changes added:

• cursorPosition tracking in TextBox state
• A componentDidUpdate that calls setSelectionRange() to restore cursor position, clamping to (this.state.value ?? '').length

The problem occurs in componentWillReceiveProps:

public componentWillReceiveProps(nextProps: ITextBoxProps) {
  if (this.state.value !== nextProps.value) {
    this.setState({ value: nextProps.value })
  }
}

When a parent component (like EnterpriseServerEntry) does not pass a value prop, nextProps.value is undefined. After each keystroke:

1. onChange fires → sets state.value = 'h', cursorPosition = {start: 1, end: 1}
2. onValueChanged callback triggers parent re-render
3. Parent re-renders TextBox (still without a value prop)
4. componentWillReceiveProps: this.state.value ('h') !== nextProps.value (undefined) → resets state.value to undefined
5. componentDidUpdate: max = (undefined ?? '').length = 0 → safeStart = Math.min(1, 0) = 0 → setSelectionRange(0, 0) → cursor jumps to position 0
6. Next keystroke inserts at position 0 → text builds up in reverse

This wasn't an issue before the IME changes because there was no componentDidUpdate reading state.value to position the cursor. The upstream desktop/desktop repo is also unaffected since it doesn't have the IME composition handling.

Fix

Add an undefined guard in componentWillReceiveProps:

public componentWillReceiveProps(nextProps: ITextBoxProps) {
  if (nextProps.value !== undefined && this.state.value !== nextProps.value) {
    this.setState({ value: nextProps.value })
  }
}

This prevents state.value from being reset to undefined when the parent simply doesn't pass a value prop, which means the cursor position clamping in componentDidUpdate uses the correct string length. This protects all uncontrolled TextBox consumers, not just the enterprise entry form.

[coocoo1112]

This was all Claude but it does fix the problem for me.

Currently it looks like this when you type https

[coocoo1112]

My first commit also fixed it, fwiw, but it seemed better to touch code that was exclusive to this repo. Up to you though.

[pol-rivero]

Works like a charm, thanks!

it seemed better to touch code that was exclusive to this repo

Absolutely, it's always better to minimize the diff with the upstream.