Fix macro resolve ordering when macros depend on other macros

[MarcelOlsen]

resolves: #1743

Problem

When a macro's resolve function depends on context provided by another macro's resolve, the dependent macro's resolve runs before the dependency. This results in the dependency's values being undefined at runtime.

const sessionsPlugin = new Elysia().macro({
  sessions: {
    resolve: () => ({ sessions: { create: () => {}, get: () => {}, delete: () => {} } }),
  },
});

const authPlugin = new Elysia()
  .use(sessionsPlugin)
  .macro({
    auth: {
      resolve: ({ sessions }) => {
        sessions.get(); // runtime error: sessions is undefined
        return { auth: { currentUser: null } };
      },
      sessions: true,
    },
  });

Root Cause

In applyMacro(), the inner loop iterates over Object.entries(macroHook) in JavaScript insertion order. For auth: { resolve: fn, sessions: true }:

1. k = 'resolve' - auth.resolve is appended to localHook first.
2. k = 'sessions' - recursive expansion adds sessions.resolve afterward.

Result: localHook.resolve = [auth.resolve, sessions.resolve] - incorrect order.

Fix

Split the single inner loop into two passes:

1. Pass 1: Process entries where k is in macro (recursive macro expansion) - dependency resolves are added first.
2. Pass 2: Process everything else (schema, introspect, detail, hooks like resolve/beforeHandle/derive) - appended after dependencies.

This produces localHook.resolve = [sessions.resolve, auth.resolve] regardless of property declaration order.

Summary by CodeRabbit

• New Features

  • Added a new discriminated macro entry type and enhanced macro typings to provide finer-grained, flag-aware type inference and propagate macro context into route typings.

• Refactor

  • Improved macro expansion to a two-pass approach for more reliable ordering and reduced redundant work during application.

• Tests

  • Added extensive tests covering macro dependency resolution across plugins, multi-level chains, parallel dependencies, deduplication, and guard/group behaviors (sync and async).

[MarcelOlsen]

@coderabbitai review

[coderabbitai]

Walkthrough

Adds discriminated macro typing and MacroContext propagation, refactors runtime macro expansion in src/index.ts to a two-pass cached-entries algorithm, exposes a new public type DiscriminatedMacroEntry, and adds extensive tests validating macro resolve dependency ordering and cross-plugin resolution scenarios.

Changes

Cohort / File(s)	Summary
Core macro runtime src/index.ts	Refactors applyMacro to a two-pass expansion using cached Object.entries: first expands nested macro keys recursively and removes raw flags, second processes remaining keys (validators, seed/introspect/detail, derive/resolve). Replaces in-loop re-expansion with cached iteration and consolidates macro handling paths. Also updates exported declarations to include DiscriminatedMacroEntry.
Macro typing src/types.ts	Adds DiscriminatedMacroEntry, MacroEntryForSelected, SingleKeyMacroEntries types and updates RouteSchemaWithResolvedMacro to include resolve. Expands macro-related type overloads to propagate MacroContext and resolve typings.
Macro tests (behavior) test/macro/macro.test.ts	Adds extensive "Macro resolve dependency ordering" tests covering cross-plugin resolution, multi-level chains, parallel dependencies, deduplication, guard/group interactions, async vs sync resolution, cycle handling, and related scenarios.
Macro tests (types) test/types/macro.ts	Adds cross-plugin macro type tests demonstrating dependent macro resolution across plugins with object and named macro variants and asserts resolved shapes.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• fix: apply macros before merging hooks in group method #1624: Also modifies macro expansion ordering and when applyMacro runs relative to hook merging — likely interacts with the runtime refactor.
• fix: named macros with function syntax now infer previous macro resolve types (#1574) #1691: Related changes to macro TypeScript overloads and MacroContext/resolve typing propagation.
• patch: 1.4.16 #1529: Prior work on macro typings and applyMacro implementation that overlaps this PR's typing and runtime edits.

Poem

🐰 I nibble flags and hop through keys,
Two-pass leaps and cached entries, please.
Types now whisper which macro is true,
Tests parade the chain and cue.
A rabbit cheers — macros made anew. 🥕

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately describes the main fix: resolving macro execution order when macros depend on other macros. It directly corresponds to the core change of implementing a two-pass expansion to ensure dependency resolves execute before dependent resolves.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

📝 Coding Plan

• Generate coding plan for human review comments

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

Tip

CodeRabbit can use your project's `biome` configuration to improve the quality of JS/TS/CSS/JSON code reviews.

Add a configuration file to your project to customize how CodeRabbit runs biome.

[coderabbitai]

✅ Actions performed

Review triggered.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[coderabbitai]

Actionable comments posted: 2

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@test/macro/macro.test.ts`:
- Around line 1593-1625: The test "deduplication preserved with shared
dependencies" records baseCallCount but never asserts it; update the test inside
the same it block (the one that builds the Elysia instance with .macro and calls
app.handle) to assert that baseCallCount equals 1 after awaiting the response
JSON so the test explicitly verifies that the shared dependency resolver (the
base resolve function) was executed only once.
- Line 1481: The test contains a no-op assertion because it references a
misspelled field `hasessions` and does not call the matcher; update the
assertion on the `response` object to use the correct property name
(`hasSessions`) and invoke the matcher method (e.g., change the call to
expect(response.hasSessions).not.toBeUndefined() or another appropriate matcher
like toBeTruthy()) so the test actually validates the presence of the
cross-plugin dependency.

---

ℹ️ Review info

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between bbaf6b7 and e5b69e6.

📒 Files selected for processing (2)

• src/index.ts
• test/macro/macro.test.ts

[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/elysia@1756

commit: 34cdbb3

[MarcelOlsen]

@coderabbitai review

[coderabbitai]

✅ Actions performed

Review triggered.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.

[MarcelOlsen]

@coderabbitai review

[coderabbitai]

✅ Actions performed

Review triggered.

Note: CodeRabbit is an incremental review system and does not re-review already reviewed commits. This command is applicable only when automatic reviews are paused.