feat(lit-query): add render method to query controllers

[EskiMojo14]

🎯 Changes

see #10711 - adds a render method based on the query status, based on the Tasks API

  render() {
    return this.repo.render({
      pending: () => html`Loading...`
      error: (query) => html`Error: ${query.error.message}`
      success: (query) => html`
        <h1>${query.data.name}</h1>
        <p>${query.data.description}</p>
        <strong>${query.data.stargazers_count} stars</strong>
      `
    })
  }

✅ Checklist

• I have followed the steps in the Contributing guide.
• I have tested this code locally with pnpm run test:pr.

🚀 Release Impact

• This change affects published code, and I have generated a changeset.
• This change is docs/CI/dev-only (no release).

Summary by CodeRabbit

• New Features

  • Added a render method to query, mutation, and infinite-query controllers for state-based rendering (pending/error/success).

• Documentation

  • Added "Rendering" guide sections with examples for queries, mutations, and infinite queries.

• Exports

  • Introduced typed rendering helpers to the Lit Query package for consistent renderer handling.

• Tests

  • Added unit tests covering render behavior across statuses and edge cases.

• Chores

  • Bumped package with a minor release entry.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

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Run ID: 78a198b5-0da1-4f7a-859f-cb831b5b6165

📥 Commits

Reviewing files that changed from the base of the PR and between 97e932a and 65cc829.

📒 Files selected for processing (1)

• packages/lit-query/src/render.ts

---

📝 Walkthrough

Walkthrough

Adds a typed rendering utility and a render convenience method to query, mutation, and infinite query controllers; wires implementations to delegate to renderResult; updates tests and documentation; and adds a changeset for a minor release bump.

Changes

Render Method Feature

Layer / File(s)	Summary
Core rendering infrastructure and types packages/lit-query/src/render.ts, packages/lit-query/src/tests/render.test.ts	Exports ResultRenderers mapped type (optional renderers per status), RendererResult conditional type (inferred return type by status), and renderResult function that selects a renderer by result.status and returns its output or undefined. Tests cover type narrowing and fallback behavior.
Query controller render method packages/lit-query/src/createQueryController.ts, packages/lit-query/src/index.ts, packages/lit-query/src/tests/query-controller.test.ts	Adds render(renderers) to QueryResultAccessor, delegates to renderResult(controller.current, renderers), re-exports renderResult, and tests pending→success, error, and undefined-when-missing-renderer cases.
Mutation controller render method packages/lit-query/src/createMutationController.ts, packages/lit-query/src/tests/mutation-controller.test.ts	Adds render(renderers) to MutationResultAccessor, delegates to renderResult, and tests idle→success, error, pending (deferred), and undefined-when-missing-renderer cases.
Infinite query controller render method packages/lit-query/src/createInfiniteQueryController.ts, packages/lit-query/src/tests/infinite-and-options.test.ts	Adds render(renderers) to InfiniteQueryResultAccessor, delegates to renderResult, and tests pending→success with page data, error, and undefined-when-missing-renderer cases.
Documentation and release notes docs/framework/lit/guides/queries.md, docs/framework/lit/guides/mutations.md, docs/framework/lit/guides/infinite-queries.md, .changeset/crisp-sloths-sneeze.md	Adds Rendering sections with Task API-style examples for pending/error/success renderers and a changeset declaring a minor bump.

🎯 3 (Moderate) | ⏱️ ~25 minutes

A rabbit's render so fine,
With pending, error, success divine,
Task API meets LitHTML's glow,
Controllers now let templates flow, 🐰✨
Query, Mutation, Infinite—all in the show!

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 57.14% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main change: adding a render method to query controllers in the lit-query package.
Description check	✅ Passed	The description covers all required template sections with details about changes, a code example, completed checklist items, and release impact confirmation.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 2

Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

docs/framework/lit/guides/mutations.md (1)

172-185: ⚠️ Potential issue | 🟡 Minor | ⚡ Quick win

Import nothing in the example snippet.

This example uses nothing (Line 179) but the imports shown in this guide only include html/LitElement, so copy-pasting the snippet can fail.

Proposed doc fix

-import { LitElement, html } from 'lit'
+import { LitElement, html, nothing } from 'lit'

🤖 Prompt for AI Agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@docs/framework/lit/guides/mutations.md` around lines 172 - 185, The example
uses the special sentinel nothing in the render() example but the shown imports
only include html/LitElement; update the snippet imports to also import nothing
(e.g., from 'lit') so copy-pasting works and the pending template can return
nothing; ensure the updated example shows nothing alongside html/LitElement
imports and keep addTodo.render(...) and the pending/error/success handlers
unchanged.

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@packages/lit-query/src/createMutationController.ts`:
- Line 72: Update the JSDoc in createMutationController.ts: replace the phrase
"query result" with "mutation result" in the comment for the accessor inside
createMutationController (the JSDoc that begins "/** Renders the query result
... */") so the description correctly refers to mutation results.

In `@packages/lit-query/src/createQueryController.ts`:
- Line 19: The import in createQueryController.ts incorrectly treats
RendererResult and ResultRenderers as runtime values; change the import to use
type-only qualifiers for RendererResult and ResultRenderers (e.g., import type {
RendererResult, ResultRenderers } from './render.js') while keeping renderResult
as a normal import, and apply the same type-only import change in
createMutationController.ts and createInfiniteQueryController.ts so all three
modules import those two symbols as types only.

---

Outside diff comments:
In `@docs/framework/lit/guides/mutations.md`:
- Around line 172-185: The example uses the special sentinel nothing in the
render() example but the shown imports only include html/LitElement; update the
snippet imports to also import nothing (e.g., from 'lit') so copy-pasting works
and the pending template can return nothing; ensure the updated example shows
nothing alongside html/LitElement imports and keep addTodo.render(...) and the
pending/error/success handlers unchanged.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: bf4f14c7-08aa-4d27-a0e7-1ce5aa4b29b2

📥 Commits

Reviewing files that changed from the base of the PR and between 514c132 and 4d2c97e.

📒 Files selected for processing (13)

• .changeset/crisp-sloths-sneeze.md
• docs/framework/lit/guides/infinite-queries.md
• docs/framework/lit/guides/mutations.md
• docs/framework/lit/guides/queries.md
• packages/lit-query/src/createInfiniteQueryController.ts
• packages/lit-query/src/createMutationController.ts
• packages/lit-query/src/createQueryController.ts
• packages/lit-query/src/index.ts
• packages/lit-query/src/render.ts
• packages/lit-query/src/tests/infinite-and-options.test.ts
• packages/lit-query/src/tests/mutation-controller.test.ts
• packages/lit-query/src/tests/query-controller.test.ts
• packages/lit-query/src/tests/render.test.ts