feat(universal-router-sdk): export encodeSwapStep from the package root

.changeset/lucky-jars-fetch.md

@@ -0,0 +1,5 @@
+---
+"@uniswap/universal-router-sdk": minor
+---
+
+Export `encodeSwapStep` from the package root so consumers can compose per-step `{commands, inputs}` plans into their own RoutePlanner without the `encodeSwaps` envelope (no Permit2 ingress, fee, or final sweep).

sdks/universal-router-sdk/src/index.ts

@@ -14,6 +14,11 @@ export {
   UniversalRouterVersion,
   isAtLeastV2_1_1,
 } from './utils/constants'
+// Per-step {commands, inputs} composition for callers that own the surrounding
+// plan: writes one step's command into the caller's RoutePlanner and applies no
+// ingress or settlement (no Permit2 transfer, fee, or sweep) — unlike
+// SwapRouter.encodeSwaps, which owns the full safety envelope.
+export { encodeSwapStep } from './utils/encodeSwapStep'
 export { CommandParser, GenericCommandParser } from './utils/commandParser'
 export type { UniversalRouterCommand, UniversalRouterCall, Param, CommandsDefinition } from './utils/commandParser'
 export type { Permit2Permit } from './utils/inputTokens'

sdks/universal-router-sdk/test/unit/exports.test.ts

@@ -0,0 +1,26 @@
+import { expect } from 'chai'
+import { encodeSwapStep as encodeSwapStepFromRoot, RoutePlanner, UniversalRouterVersion } from '../../src'
+import { encodeSwapStep } from '../../src/utils/encodeSwapStep'
+import { V3SwapExactIn } from '../../src/types/encodeSwaps'
+import { ROUTER_AS_RECIPIENT } from '../../src/utils/constants'
+import { CommandType } from '../../src/utils/routerCommands'
+
+describe('package exports', () => {
+  it('re-exports encodeSwapStep from the package root', () => {
+    expect(encodeSwapStepFromRoot).to.equal(encodeSwapStep)
+
+    // Sanity: the export is usable standalone — one step, one command, no envelope.
+    const planner = new RoutePlanner()
+    const step: V3SwapExactIn = {
+      type: 'V3_SWAP_EXACT_IN',
+      recipient: ROUTER_AS_RECIPIENT,
+      amountIn: '1000000',
+      amountOutMin: '0',
+      // USDC -(500)-> WETH packed path
+      path: '0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb480001f4c02aaa39b223fe8d0a0e5c4f27ead9083c756cc2',
+    }
+    encodeSwapStepFromRoot(planner, step, UniversalRouterVersion.V2_0)
+    expect(planner.commands).to.equal('0x' + CommandType.V3_SWAP_EXACT_IN.toString(16).padStart(2, '0'))
+    expect(planner.inputs.length).to.equal(1)
+  })
+})