From 087ac07a14fd19f4c4b0d66cee686dce53de78a9 Mon Sep 17 00:00:00 2001
From: John <John60676@qq.com>
Date: Sat, 16 Jan 2021 19:08:52 +0800
Subject: [PATCH] refactor(utils): enhanced number formatter (#7921)

---
 src/utils/format/number.ts   | 9 ++++++++-
 src/utils/test/index.spec.js | 4 ++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/utils/format/number.ts b/src/utils/format/number.ts
index 79317a359..bd7bae161 100644
--- a/src/utils/format/number.ts
+++ b/src/utils/format/number.ts
@@ -4,6 +4,7 @@ export function range(num: number, min: number, max: number): number {
 
 function trimExtraChar(value: string, char: string, regExp: RegExp) {
   const index = value.indexOf(char);
+  let prefix = '';
 
   if (index === -1) {
     return value;
@@ -13,7 +14,13 @@ function trimExtraChar(value: string, char: string, regExp: RegExp) {
     return value.slice(0, index);
   }
 
-  return value.slice(0, index + 1) + value.slice(index).replace(regExp, '');
+  if (char === '.' && value.match(/^(\.|-\.)/)) {
+    prefix = index ? '-0' : '0';
+  }
+
+  return (
+    prefix + value.slice(0, index + 1) + value.slice(index).replace(regExp, '')
+  );
 }
 
 export function formatNumber(
diff --git a/src/utils/test/index.spec.js b/src/utils/test/index.spec.js
index eb263eaa2..86b54980a 100644
--- a/src/utils/test/index.spec.js
+++ b/src/utils/test/index.spec.js
@@ -116,6 +116,10 @@ test('formatNumber', () => {
   expect(formatNumber('-1.2', true)).toEqual('-1.2');
   expect(formatNumber('-1.2-', true)).toEqual('-1.2');
   expect(formatNumber('123-')).toEqual('123');
+
+  // special cases
+  expect(formatNumber('.1', true)).toEqual('0.1');
+  expect(formatNumber('-.1')).toEqual('-0.1');
 });
 
 test('addUnit', () => {