templateLock is a property of InnerBlocks that allows you to "lock" an InnerBlocks area.

As implemented, it is somewhat limited, with only three options: prevent all modifications, prevent inserting, and disable locking (for nested contexts).

I'd like to see a slightly more flexible approach, which reflects different needs in various nesting situations. In particular, templateLock doesn't currently have an option to disable inserting/removing while preserving movement, which I think could be a fairly common use-case (and what prompted me to submit this).

In this more granular approach, you would pass an array of blocked actions:

<InnerBlocks templateLock={['insert', 'move', 'remove']} />
// Could also be aliased as "all"

<InnerBlocks templateLock={['move']} />
// Newly-possible option — allow inserting/removing but no movement

<InnerBlocks templateLock={['insert', 'remove']} />
// Another newly-possible option — _only_ allows moving

<InnerBlocks templateLock={[]} />
// Pass an empty array, or "none", to undo the lock

// You could also continue to pass strings in to preserve back-compat
// (or just make for fewer characters in a user's code)…
<InnerBlocks templateLock="all" />
<InnerBlocks templateLock="none" />
<InnerBlocks templateLock="insert" />
<InnerBlocks templateLock="remove" />

Further, to better reflect that templateLock does not require setting a template (for example if you're building your block structure programatically by dispatching insertBlocks actions), it could be renamed disabledBlockActions (e.g. <InnerBlocks disabledBlockActions={['move', 'remove']} />), or something similar (perhaps disabledBlockUIActions to be absolutely clear to developers that the locks only apply to the UI; you can still programmatically alter the block structure).

I believe this flexibility would be super valuable for anyone doing more complex things with InnerBlocks. To me, InnerBlocks is one of the most exciting features in Gutenberg and I think strengthening this API will have awesome benefits for developers.

(Note: my use-case is most focussed on InnerBlocks, but I suspect these changes could be of use to custom post type templates as well!)