fix: should format max/min with precision

src/InputNumber.tsx

@@ -2,15 +2,29 @@ import * as React from 'react';
 import classNames from 'classnames';
 import KeyCode from 'rc-util/lib/KeyCode';
 import { composeRef } from 'rc-util/lib/ref';
-import getMiniDecimal, { DecimalClass, toFixed, ValueType } from './utils/MiniDecimal';
+import getMiniDecimal, {
+  DecimalClass,
+  roundDownUnsignedDecimal,
+  roundUpUnsignedDecimal,
+  toFixed,
+  ValueType
+} from './utils/MiniDecimal';
 import StepHandler from './StepHandler';
-import { getNumberPrecision, num2str, validateNumber } from './utils/numberUtil';
+import { getNumberPrecision, num2str, trimNumber, validateNumber } from './utils/numberUtil';
 import useCursor from './hooks/useCursor';
 import useUpdateEffect from './hooks/useUpdateEffect';
 import useFrame from './hooks/useFrame';
 
 /**
  * We support `stringMode` which need handle correct type when user call in onChange
+ * format max or min value
+ * 1. if isInvalid return null
+ * 2. if precision is undefined, return decimal
+ * 3. format with precision
+ *    I. if max > 0, round down with precision. Example: max= 3.5, precision=0  afterFormat: 3
+ *    II. if max < 0, round up with precision. Example: max= -3.5, precision=0  afterFormat: -4
+ *    III. if min > 0, round up with precision. Example: min= 3.5, precision=0  afterFormat: 4
+ *    IV. if min < 0, round down with precision. Example: max= -3.5, precision=0  afterFormat: -3
  */
 const getDecimalValue = (stringMode: boolean, decimalValue: DecimalClass) => {
   if (stringMode || decimalValue.isEmpty()) {
@@ -20,9 +34,24 @@ const getDecimalValue = (stringMode: boolean, decimalValue: DecimalClass) => {
   return decimalValue.toNumber();
 };
 
-const getDecimalIfValidate = (value: ValueType) => {
+const getDecimalIfValidate = (value: ValueType, precision: number | undefined, isMax?: boolean) => {
   const decimal = getMiniDecimal(value);
-  return decimal.isInvalidate() ? null : decimal;
+  if (decimal.isInvalidate()) {
+    return null;
+  }
+
+  if (precision === undefined) {
+    return decimal;
+  }
+
+  const {negative, integerStr, decimalStr, negativeStr} = trimNumber(decimal.toString());
+  const unSignedNumberStr = integerStr +'.' +  decimalStr;
+
+  if ((isMax && !negative) || (!isMax && negative)) {
+    return getMiniDecimal(negativeStr +  roundDownUnsignedDecimal(unSignedNumberStr, precision));
+  } else {
+    return getMiniDecimal(negativeStr +  roundUpUnsignedDecimal(unSignedNumberStr, precision));
+  }
 };
 
 export interface InputNumberProps<T extends ValueType = ValueType>
@@ -232,8 +261,8 @@ const InputNumber = React.forwardRef(
     }
 
     // >>> Max & Min limit
-    const maxDecimal = React.useMemo(() => getDecimalIfValidate(max), [max]);
-    const minDecimal = React.useMemo(() => getDecimalIfValidate(min), [min]);
+    const maxDecimal = React.useMemo(() => getDecimalIfValidate(max, precision, true), [max, precision]);
+    const minDecimal = React.useMemo(() => getDecimalIfValidate(min, precision, false), [min, precision]);
 
     const upDisabled = React.useMemo(() => {
       if (!maxDecimal || !decimalValue || decimalValue.isInvalidate()) {

src/utils/MiniDecimal.ts

@@ -264,6 +264,31 @@ export default function getMiniDecimal(value: ValueType): DecimalClass {
   return new NumberDecimal(value);
 }
 
+/**
+ * round up an unsigned number str, like: 1.4 -> 2, 1.5 -> 2
+ */
+export function roundUpUnsignedDecimal(numStr: string, precision: number) {
+  const {integerStr, decimalStr} = trimNumber(numStr);
+  const advancedDecimal = getMiniDecimal(integerStr + '.' + decimalStr).add(
+    `0.${'0'.repeat(precision)}${5}`,
+  );
+  return toFixed(advancedDecimal.toString(), '.', precision);
+}
+
+/**
+ * round up an unsigned number str, like: 1.4 -> 1, 1.5 -> 1
+ */
+export function roundDownUnsignedDecimal(numStr: string,  precision: number) {
+  const {negativeStr, integerStr, decimalStr} = trimNumber(numStr);
+  const numberWithoutDecimal = `${negativeStr}${integerStr}`;
+  if (precision === 0) {
+    return integerStr;
+  }
+  return `${numberWithoutDecimal}.${decimalStr
+    .padEnd(precision, '0')
+    .slice(0, precision)}`;
+}
+
 /**
  * Align the logic of toFixed to around like 1.5 => 2
  */

tests/input.test.tsx

@@ -59,6 +59,27 @@ describe('InputNumber.Input', () => {
     expect(wrapper.getInputValue()).toEqual('-98');
   });
 
+  it('negative min with higher precision', () => {
+    const wrapper = prepareWrapper('-4', {min: -3.5, precision: 0});
+    expect(wrapper.getInputValue()).toEqual('-3');
+  });
+
+  it('positive min with higher precision', () => {
+    const wrapper = prepareWrapper('4', {min: 3.5, precision: 0});
+    expect(wrapper.getInputValue()).toEqual('4');
+  });
+
+  it('negative max with higher precision', () => {
+    const wrapper = prepareWrapper('-4', {max: -3.5, precision: 0});
+    expect(wrapper.getInputValue()).toEqual('-4');
+  });
+
+  it('positive max with higher precision', () => {
+    const wrapper = prepareWrapper('4', {max: 3.5, precision: 0});
+    expect(wrapper.getInputValue()).toEqual('3');
+  });
+
+
   // https://github.com/ant-design/ant-design/issues/9439
   it('input negative zero', () => {
     const wrapper = prepareWrapper('-0', {}, true);

tests/util.test.tsx

@@ -2,8 +2,10 @@ import getMiniDecimal, {
   BigIntDecimal,
   DecimalClass,
   NumberDecimal,
-  ValueType,
+  roundDownUnsignedDecimal,
+  roundUpUnsignedDecimal,
   toFixed,
+  ValueType,
 } from '../src/utils/MiniDecimal';
 
 jest.mock('../src/utils/supportUtil');
@@ -150,5 +152,21 @@ describe('InputNumber.Util', () => {
       // expect(toFixed('77.88', '.', 1)).toEqual('77.9');
       expect(toFixed('-77.88', '.', 1)).toEqual('-77.9');
     });
+
+    it('round down', () => {
+      expect(roundDownUnsignedDecimal('77.89',  1)).toEqual('77.8');
+      expect(roundDownUnsignedDecimal('77.1',  2)).toEqual('77.10');
+      expect(roundDownUnsignedDecimal('77.81', 1)).toEqual('77.8');
+      expect(roundDownUnsignedDecimal('77.50', 1)).toEqual('77.5');
+      expect(roundDownUnsignedDecimal('77.5999', 0)).toEqual('77');
+      expect(roundDownUnsignedDecimal('77.0001', 0)).toEqual('77');
+    })
+    it('round up', () => {
+      expect(roundUpUnsignedDecimal('77.89', 1)).toEqual('77.9');
+      expect(roundUpUnsignedDecimal('77.81', 1)).toEqual('77.9');
+      expect(roundUpUnsignedDecimal('77.89', 0)).toEqual('78');
+      expect(roundUpUnsignedDecimal('77.599', 0)).toEqual('78');
+      expect(roundUpUnsignedDecimal('77.01', 0)).toEqual('78');
+    })
   });
 });