feat(perps): export normalized Scale price ladder

packages/perps-controller/CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Add `normalizeHyperLiquidScalePriceLadder` for shared Scale price normalization ([#10021](https://github.com/MetaMask/core/pull/10021))
+
 ## [15.0.0]
 
 ### Added

packages/perps-controller/src/index.ts

@@ -586,6 +586,7 @@ export {
   buildTriggerOrderType,
   buildPositionTriggerOrderFromOrder,
   computeScalePriceLadder,
+  normalizeHyperLiquidScalePriceLadder,
   computeChaseQuotePrice,
   getPriceTick,
   splitScaleSizes,

packages/perps-controller/src/providers/HyperLiquidProvider.ts

@@ -210,10 +210,10 @@ import {
   calculateFinalPositionSize,
   calculateOrderPriceAndSize,
   computeChaseQuotePrice,
-  computeScalePriceLadder,
   floorToSizeDecimals,
   formatPartialTpslSize,
   getPriceTick,
+  normalizeHyperLiquidScalePriceLadder,
   splitScaleSizes,
   validateOrderPrecision,
 } from '../utils/orderCalculations.js';
@@ -5826,11 +5826,12 @@ export class HyperLiquidProvider implements PerpsProvider {
       throw new Error(PERPS_ERROR_CODES.ORDER_SCALE_COUNT_INVALID);
     }
 
-    const prices = computeScalePriceLadder({
+    const prices = normalizeHyperLiquidScalePriceLadder({
       minPrice: parseFloat(scaleMinPrice),
       maxPrice: parseFloat(scaleMaxPrice),
       count: scaleNumOrders,
-    }).map((price) => formatHyperLiquidPrice({ price, szDecimals }));
+      szDecimals,
+    });
 
     if (new Set(prices).size !== prices.length) {
       throw new Error(PERPS_ERROR_CODES.ORDER_SCALE_RANGE_INVALID);

packages/perps-controller/src/utils/orderCalculations.ts

@@ -432,6 +432,29 @@ export function computeScalePriceLadder(params: {
   );
 }
 
+/**
+ * Build the exact price strings a HyperLiquid Scale order will receive.
+ *
+ * @param params - Ladder and asset precision parameters.
+ * @param params.minPrice - Lowest price in the ladder.
+ * @param params.maxPrice - Highest price in the ladder.
+ * @param params.count - Number of rungs.
+ * @param params.szDecimals - Asset size precision used for price formatting.
+ * @returns The normalized rung prices, ascending.
+ */
+export function normalizeHyperLiquidScalePriceLadder(params: {
+  minPrice: number;
+  maxPrice: number;
+  count: number;
+  szDecimals: number;
+}): string[] {
+  const { szDecimals, ...ladderParams } = params;
+
+  return computeScalePriceLadder(ladderParams).map((price) =>
+    formatHyperLiquidPrice({ price, szDecimals }),
+  );
+}
+
 /**
  * Split a scale placement's total size across its ladder rungs.
  *

packages/perps-controller/tests/src/utils/orderCalculations.scale-ladder.test.ts

@@ -3,6 +3,7 @@ import {
   computeChaseQuotePrice,
   computeScalePriceLadder,
   getPriceTick,
+  normalizeHyperLiquidScalePriceLadder,
   splitScaleSizes,
 } from '../../../src/utils/orderCalculations.js';
 
@@ -54,6 +55,59 @@ describe('orderCalculations - scale ladder', () => {
     });
   });
 
+  describe('normalizeHyperLiquidScalePriceLadder', () => {
+    it('formats every rung for HyperLiquid', () => {
+      expect(
+        normalizeHyperLiquidScalePriceLadder({
+          minPrice: 100,
+          maxPrice: 200,
+          count: 3,
+          szDecimals: 3,
+        }),
+      ).toStrictEqual(['100', '150', '200']);
+    });
+
+    it('applies the asset precision and significant-figure limits', () => {
+      expect(
+        normalizeHyperLiquidScalePriceLadder({
+          minPrice: 1234.567,
+          maxPrice: 1234.767,
+          count: 3,
+          szDecimals: 3,
+        }),
+      ).toStrictEqual(['1234.6', '1234.7', '1234.8']);
+    });
+
+    it('preserves duplicate formatted rungs for callers to reject', () => {
+      const prices = normalizeHyperLiquidScalePriceLadder({
+        minPrice: 100.123456,
+        maxPrice: 100.123457,
+        count: 3,
+        szDecimals: 3,
+      });
+
+      expect(prices).toStrictEqual(['100.12', '100.12', '100.12']);
+      expect(new Set(prices).size).toBe(1);
+    });
+
+    it.each([
+      [
+        'an invalid count',
+        { minPrice: 100, maxPrice: 200, count: 1, szDecimals: 3 },
+        PERPS_ERROR_CODES.ORDER_SCALE_COUNT_INVALID,
+      ],
+      [
+        'an invalid range',
+        { minPrice: 200, maxPrice: 100, count: 3, szDecimals: 3 },
+        PERPS_ERROR_CODES.ORDER_SCALE_RANGE_INVALID,
+      ],
+    ])('propagates %s', (_label, params, errorCode) => {
+      expect(() => normalizeHyperLiquidScalePriceLadder(params)).toThrow(
+        errorCode,
+      );
+    });
+  });
+
   describe('splitScaleSizes', () => {
     it('splits a size that divides evenly', () => {
       expect(