chore(trading): market's tick size

libs/deal-ticket/src/components/deal-ticket/deal-ticket-price-tp-sl.tsx

@@ -12,6 +12,7 @@ import {
   Pill,
 } from '@vegaprotocol/ui-toolkit';
 import { useT } from '../../use-t';
+import { determinePriceStep } from '../../utils/step';
 
 export interface DealTicketPriceTakeProfitStopLossProps {
   control: Control<OrderFormValues>;
@@ -30,7 +31,7 @@ export const DealTicketPriceTakeProfitStopLoss = ({
 }: DealTicketPriceTakeProfitStopLossProps) => {
   const t = useT();
   const validateAmount = useValidateAmount();
-  const priceStep = toDecimal(market?.decimalPlaces);
+  const priceStep = determinePriceStep(market);
 
   const renderTakeProfitError = () => {
     if (takeProfitError) {

libs/deal-ticket/src/components/deal-ticket/deal-ticket-size-iceberg.tsx

@@ -1,7 +1,7 @@
 import { Controller, type Control } from 'react-hook-form';
 import type { Market } from '@vegaprotocol/markets';
 import type { OrderFormValues } from '../../hooks/use-form-values';
-import { toDecimal, useValidateAmount } from '@vegaprotocol/utils';
+import { useValidateAmount } from '@vegaprotocol/utils';
 import {
   TradingFormGroup,
   TradingInput,
@@ -9,6 +9,7 @@ import {
   Tooltip,
 } from '@vegaprotocol/ui-toolkit';
 import { useT } from '../../use-t';
+import { determineSizeStep } from '../../utils/step';
 
 export interface DealTicketSizeIcebergProps {
   control: Control<OrderFormValues>;
@@ -29,7 +30,7 @@ export const DealTicketSizeIceberg = ({
 }: DealTicketSizeIcebergProps) => {
   const t = useT();
   const validateAmount = useValidateAmount();
-  const sizeStep = toDecimal(market?.positionDecimalPlaces);
+  const sizeStep = determineSizeStep(market);
 
   const renderPeakSizeError = () => {
     if (peakSizeError) {

libs/deal-ticket/src/components/deal-ticket/deal-ticket-stop-order.tsx

@@ -8,7 +8,6 @@ import {
   formatForInput,
   formatValue,
   removeDecimal,
-  toDecimal,
   useValidateAmount,
 } from '@vegaprotocol/utils';
 import { type Control, type UseFormWatch } from 'react-hook-form';
@@ -59,6 +58,7 @@ import { KeyValue } from './key-value';
 import { useDataProvider } from '@vegaprotocol/data-provider';
 import { stopOrdersProvider } from '@vegaprotocol/orders';
 import { useT } from '../../use-t';
+import { determinePriceStep, determineSizeStep } from '../../utils/step';
 
 export interface StopOrderProps {
   market: Market;
@@ -904,8 +904,8 @@ export const StopOrder = ({ market, marketPrice, submit }: StopOrderProps) => {
     market.tradableInstrument.instrument.metadata.tags
   );
 
-  const sizeStep = toDecimal(market?.positionDecimalPlaces);
-  const priceStep = toDecimal(market?.decimalPlaces);
+  const sizeStep = determineSizeStep(market);
+  const priceStep = determinePriceStep(market);
 
   useController({
     name: 'type',

libs/deal-ticket/src/components/deal-ticket/deal-ticket.tsx

@@ -32,7 +32,6 @@ import {
   toBigNum,
   removeDecimal,
   useValidateAmount,
-  toDecimal,
   formatForInput,
   formatValue,
 } from '@vegaprotocol/utils';
@@ -82,6 +81,7 @@ import { DocsLinks } from '@vegaprotocol/environment';
 import { useT } from '../../use-t';
 import { DealTicketPriceTakeProfitStopLoss } from './deal-ticket-price-tp-sl';
 import uniqueId from 'lodash/uniqueId';
+import { determinePriceStep, determineSizeStep } from '../../utils/step';
 
 export const REDUCE_ONLY_TOOLTIP =
   '"Reduce only" will ensure that this order will not increase the size of an open position. When the order is matched, it will only trade enough volume to bring your open volume towards 0 but never change the direction of your position. If applied to a limit order that is not instantly filled, the order will be stopped.';
@@ -419,11 +419,12 @@ export const DealTicket = ({
     },
   });
 
-  const priceStep = toDecimal(market?.decimalPlaces);
-  const sizeStep = toDecimal(market?.positionDecimalPlaces);
+  const sizeStep = determineSizeStep(market);
   const quoteName = getQuoteName(market);
   const isLimitType = type === Schema.OrderType.TYPE_LIMIT;
 
+  const priceStep = determinePriceStep(market);
+
   return (
     <form
       onSubmit={

libs/deal-ticket/src/utils/step.ts

@@ -0,0 +1,21 @@
+import type { Market } from '@vegaprotocol/markets';
+import { toBigNum, toDecimal } from '@vegaprotocol/utils';
+
+export const determinePriceStep = (
+  market: Pick<Market, 'decimalPlaces' | 'tickSize'>
+) => {
+  let priceStep = toDecimal(market.decimalPlaces);
+
+  const scaledTickSize = toBigNum(market.tickSize, market.decimalPlaces);
+  if (scaledTickSize.isGreaterThan(0)) {
+    priceStep = scaledTickSize.toString();
+  }
+
+  return priceStep;
+};
+
+export const determineSizeStep = (
+  market: Pick<Market, 'positionDecimalPlaces'>
+) => {
+  return toDecimal(market.positionDecimalPlaces);
+};

libs/markets/src/lib/markets.graphql

@@ -2,6 +2,7 @@ fragment MarketFields on Market {
   id
   decimalPlaces
   positionDecimalPlaces
+  tickSize
   state
   tradingMode
   parentMarketID

libs/utils/src/lib/format/number.ts

@@ -18,18 +18,42 @@ export const getUnlimitedThreshold = (decimalPlaces: number) =>
 const MIN_FRACTION_DIGITS = 2;
 const MAX_FRACTION_DIGITS = 20;
 
-export function toDecimal(numberOfDecimals: number) {
-  return new BigNumber(1)
-    .dividedBy(new BigNumber(10).exponentiatedBy(numberOfDecimals))
-    .toString(10);
-}
-
+/**
+ * Converts "raw" value to a decimal representation as a `BigNumber`
+ *
+ * Example:
+ *  `toBigNum(1, 3)` -> 0.001
+ *  `toBigNum(1234, 2)` -> 12.34
+ *
+ * @param rawValue The "raw" value
+ * @param decimals The number of decimal places
+ */
 export function toBigNum(
   rawValue: string | number | BigNumber,
   decimals: number
 ): BigNumber {
-  const divides = new BigNumber(10).exponentiatedBy(decimals);
-  return new BigNumber(rawValue || 0).dividedBy(divides);
+  const d = new BigNumber(10).exponentiatedBy(decimals);
+  return new BigNumber(rawValue || 0).dividedBy(d);
+}
+
+/**
+ * Reverses `toBigNum` - converts given decimal representation
+ * as a "raw" value (`BigNumber`)
+ *
+ * Example:
+ *   `formBigNum(5.4321, 4)` -> 54321
+ *   `formBigNum(112.34, 2)` -> 11234
+ */
+export const fromBigNum = (
+  input: string | number | BigNumber,
+  decimals: number
+) => {
+  const d = new BigNumber(10).exponentiatedBy(decimals);
+  return new BigNumber(input).times(d);
+};
+
+export function toDecimal(numberOfDecimals: number) {
+  return toBigNum(1, numberOfDecimals).toString(10);
 }
 
 export function addDecimal(

libs/utils/src/lib/validate/validate-amount.spec.ts

@@ -0,0 +1,38 @@
+import { validateAgainstStep } from './validate-amount';
+
+describe('validateAgainstStep', () => {
+  it('fails when step is an empty string', () => {
+    expect(validateAgainstStep('', '1234')).toEqual(false);
+  });
+
+  it.each([
+    [0, 0],
+    [1234567890, 0],
+    [0.03, 0.03],
+    [0.09, 0.03],
+    [0.27, 0.03],
+    [1, 1],
+    [123, 1],
+    [4, 2],
+    [8, 2],
+  ])(
+    'checks whether given value (%s) IS a multiple of given step (%s)',
+    (value, step) => {
+      expect(validateAgainstStep(step, value)).toEqual(true);
+    }
+  );
+
+  it.each([
+    [1, 2],
+    [0.1, 0.003],
+    [1.11, 0.1],
+    [123.1, 1],
+    [222, 221],
+    [NaN, 1],
+  ])(
+    'checks whether given value (%s) IS NOT a multiple of given step (%s)',
+    (value, step) => {
+      expect(validateAgainstStep(step, value)).toEqual(false);
+    }
+  );
+});

libs/utils/src/lib/validate/validate-amount.ts

@@ -1,35 +1,24 @@
 import { useCallback } from 'react';
 import { useT } from '../use-t';
+import BigNumber from 'bignumber.js';
 
 export const useValidateAmount = () => {
   const t = useT();
   return useCallback(
     (step: number | string, field: string) => {
-      const [, stepDecimals = ''] = String(step).split('.');
-
       return (value?: string) => {
-        if (Number(step) > 1) {
-          if (Number(value) % Number(step) > 0) {
-            return t(
-              '{{field}} must be a multiple of {{step}} for this market',
-              {
-                field,
-                step,
-              }
-            );
-          }
-          return true;
-        }
-        const [, valueDecimals = ''] = (value || '').split('.');
-        if (stepDecimals.length < valueDecimals.length) {
-          if (stepDecimals === '') {
+        const isValid = validateAgainstStep(step, value);
+        if (!isValid) {
+          if (new BigNumber(step).isEqualTo(1)) {
             return t('{{field}} must be whole numbers for this market', {
               field,
+              step,
             });
           }
-          return t('{{field}} accepts up to {{decimals}} decimal places', {
+
+          return t('{{field}} must be a multiple of {{step}} for this market', {
             field,
-            decimals: stepDecimals.length,
+            step,
           });
         }
         return true;
@@ -38,3 +27,24 @@ export const useValidateAmount = () => {
     [t]
   );
 };
+
+const isMultipleOf = (value: BigNumber, multipleOf: BigNumber) =>
+  value.modulo(multipleOf).isZero();
+
+export const validateAgainstStep = (
+  step: string | number,
+  input?: string | number
+) => {
+  const stepValue = new BigNumber(step);
+  if (stepValue.isNaN()) {
+    // unable to check if step is not a number
+    return false;
+  }
+  if (stepValue.isZero()) {
+    // every number is valid when step is zero
+    return true;
+  }
+
+  const value = new BigNumber(input || '');
+  return isMultipleOf(value, stepValue);
+};