Blueprints: Fix creating documents from blueprints (closes #21996)

[nielslyngsoe]

cherry-picked fix from #22422

Description

Fixes #21996

Testing

May be tricky to reproduce unless you want a copy of the database that shows the error, but it should be enough to verify that new documents can be created when selected from a list of blueprints, and you can successfully create one, scaffold it, then change your mind and create again from a different blueprint.

[claude]

Claude finished @nielslyngsoe's task in 1m 27s —— View job

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PR Review

Target: origin/release/17.4.0 · Based on commit: a66769a42b64b6e53d6e34e11b68bba53746d869 · Skipped: 0 noise files out of 1 total

Adds a resetState() call before scaffolding from a blueprint, fixing stale workspace state when a user switches blueprints mid-flow, plus loading state bookends around the async fetch.

• Other changes: Workspace state is now reset whenever create() is called with a blueprintUnique — this is a behavioral change that fixes the bug (stale scaffold data from a previous blueprint selection is cleared).

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Suggestions

• document-workspace.context.ts:244-254: loading.removeState('blueprint-fetch') is duplicated across two exit paths. If scaffoldByUnique were to throw (e.g., unexpected exception), the loading state would never be cleared. A try/finally block is more robust:

  this.loading.addState({ unique: 'blueprint-fetch' });
  try {
      const { data } = await blueprintRepository.scaffoldByUnique(blueprintUnique);
      if (!data) throw new Error('Blueprint data is missing');
      return this.createScaffold({ ... });
  } finally {
      this.loading.removeState('blueprint-fetch');
  }

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Approved

The fix is correct and well-scoped. resetState() is the key change needed to clear stale scaffold state between blueprint selections, and the loading state is properly managed on both exit paths. The try/finally refactor is a nice-to-have for robustness, but the current code is functionally safe given Umbraco's data-flow pattern (repositories return { data, error } rather than throwing).

Applied labels: area/frontend, category/ux

[Copilot]

Pull request overview

Fixes an intermittent blank/grey workspace when creating documents from blueprints by resetting workspace state and showing a loading state before fetching the blueprint scaffold, reducing the race window described in #21996.

Changes:

• Reset document workspace state earlier when creating from a blueprint.
• Add/remove a dedicated loading state around the blueprint scaffold fetch.
• Ensure loading state is removed before throwing when blueprint data is missing.