perf(designer): reduce panel rerenders

[ccastrotrejo]

Commit Type

• feature - New functionality
• fix - Bug fix
• refactor - Code restructuring without behavior change
• perf - Performance improvement
• docs - Documentation update
• test - Test-related changes
• chore - Maintenance/tooling

Risk Level

• Low - Minor changes, limited scope
• Medium - Moderate changes, some user impact
• High - Major changes, significant user/system impact

What & Why

Panel selector hooks created memoized selectors during render and returned fresh empty arrays or objects for missing optional state. Unrelated panel actions therefore changed selector result identity and re-rendered consumers. This change uses direct selectors with stable fallbacks in both designer implementations and also overlaps two independent connection service requests instead of awaiting them serially.

Impact of Change

• Users: Designer panels avoid unnecessary updates, and managed-identity connection changes no longer serialize independent network latency.
• Developers: Panel hooks now follow the repository's direct-selector convention; regression tests document referential-stability requirements.
• System: Unrelated panel dispatches produce zero extra renders for fallback consumers. Independent connector and connection reads complete in roughly the slower request's duration instead of their combined duration.

Test Plan

• Unit tests added/updated
• E2E tests added/updated
• Manual testing completed
• Tested in: Targeted Vitest selector and connection suites; designer and designer-v2 type checks; designer-v2 library build

Contributors

@ccastrotrejo_microsoft

Screenshots/Videos

N/A - no visual changes.

[github-actions]

🤖 AI PR Validation Report

PR Review Results

Thank you for your submission! Here's detailed feedback on your PR title and body compliance:

✅ PR Title

• Current: perf(designer): reduce panel rerenders
• Issue: None — uses the valid perf(scope): prefix and is descriptive of the actual change.
• Recommendation: No change needed.

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✅ Commit Type

• Exactly one type selected (perf - Performance improvement).
• Matches the diff: selector refactors to eliminate spurious re-renders and a serial→concurrent connection fetch. Good fit.

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✅ Risk Level

• Exactly one box selected (Medium) and the risk:medium label matches the body. My advised estimate is medium as well: these are state-management/selector changes in shipped libs/designer and libs/designer-v2 runtime code plus a connection-flow concurrency change — moderate user impact, no security/API/shared-utility breakage. Declared level matches advised level. ✅

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✅ What & Why

• Current: Clear explanation of the per-render createSelector fallback problem and the concurrent connection-read optimization.
• Issue: None.
• Recommendation: No change needed.

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✅ Impact of Change

• All three audiences (Users, Developers, System) are filled with specific, accurate detail.
• Recommendation:
  • Users: Already documented (fewer unnecessary panel updates; faster managed-identity connection changes).
  • Developers: Already documented (direct-selector convention; referential-stability regression tests).
  • System: Already documented (zero extra renders on unrelated dispatches; overlapped network reads).

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✅ Test Plan

• Unit tests added/updated in both libs/designer-v2/.../panelSelectors.perf.spec.tsx and libs/designer/.../panelSelectors.perf.spec.tsx, capturing before/after referential stability. Test requirement satisfied.

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✅ Contributors

• Credited @ccastrotrejo_microsoft. Good.

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⚠️ Screenshots/Videos

• Marked N/A - no visual changes. Correct — the diff touches state selectors and connection logic, not visual UI, so screenshots are not required.

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Summary Table

Section	Status	Recommendation
Title	✅	No change needed
Commit Type	✅	No change needed
Risk Level	✅	Medium is correct and matches label
What & Why	✅	No change needed
Impact of Change	✅	No change needed
Test Plan	✅	Unit tests present
Contributors	✅	Credited
Screenshots/Videos	⚠️	N/A acceptable — non-visual change

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All required checks pass. This PR is compliant with the team template and cleared to merge.

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Powered by: Copilot CLI (claude-opus-4.8) | Last updated: Thu, 16 Jul 2026 18:23:24 GMT

[Copilot]

Pull request overview

This PR improves performance in the Logic Apps Designer (both designer and designer-v2) by making panel selector hooks return referentially-stable values for optional state and by avoiding sequential (waterfall) network reads during managed-identity connection updates.

Changes:

• Replaced per-render createSelector usage in panel selector hooks with direct selectors, eliminating unnecessary selector recreation and avoiding identity churn.
• Introduced stable module-level empty fallbacks ({} / []) for optional panel selection state to prevent spurious rerenders on unrelated dispatches.
• Parallelized independent connector + connection reads via Promise.all to reduce latency when updating managed-identity connection configuration.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
libs/designer/src/lib/core/state/panel/panelSelectors.ts	Switches panel hooks to direct selectors and adds a stable {} fallback for alternateSelectedNode to prevent unnecessary rerenders.
libs/designer/src/lib/core/state/panel/test/panelSelectors.perf.spec.tsx	Adds a regression perf test verifying referential stability for the v1 selector fallback behavior.
libs/designer-v2/src/lib/core/state/panel/panelSelectors.ts	Applies the same selector changes for v2, adding stable {} and [] fallbacks used by operation panel selection hooks.
libs/designer-v2/src/lib/core/state/test/panelSelectors.perf.spec.tsx	Adds regression perf tests covering both stable [] and {} selector fallback behavior in v2.
libs/designer-v2/src/lib/core/actions/bjsworkflow/connections.ts	Fetches connector + connection concurrently during identity update to avoid serialized network latency.