Disable padding in @source inline(…) brace expansion (#17491)

The padding code we had was incorrect as it would always pad on the
largest string representation. So for an input like this:


```
@source inline("z-{10..100..10}");
```

It would create the following candidates: 

- `z-010`
- `z-020`
- `z-030`
- `z-040`
- `z-050`
- `z-060`
- `z-070`
- `z-060`
- `z-070`
- `z-100`

Instead of fixing the padding logic we realized that Tailwind utilities
don't need padding at all so this PR removes this feature

## Test plan

- Added the following to the Vite playground: `@source
inline("z-{10..100..10}");`
- Ensure it works: 

![image](https://github.com/user-attachments/assets/f4714729-4ef7-4678-a531-70b471e75e6e)

CHANGELOG.md

@@ -7,7 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-- Nothing yet!
+### Fixed
+
+- Disable padding in `@source inline(…)` brace expansion ([#17491](https://github.com/tailwindlabs/tailwindcss/pull/17491))
 
 ## [4.1.0] - 2025-04-01
 

packages/tailwindcss/src/utils/brace-expansion.test.ts

@@ -14,14 +14,16 @@ describe('expand(…)', () => {
     ['a/{0..5}/b', ['a/0/b', 'a/1/b', 'a/2/b', 'a/3/b', 'a/4/b', 'a/5/b']],
     ['a/{-5..0}/b', ['a/-5/b', 'a/-4/b', 'a/-3/b', 'a/-2/b', 'a/-1/b', 'a/0/b']],
     ['a/{0..-5}/b', ['a/0/b', 'a/-1/b', 'a/-2/b', 'a/-3/b', 'a/-4/b', 'a/-5/b']],
-
-    // Numeric range with padding
-    ['a/{00..05}/b', ['a/00/b', 'a/01/b', 'a/02/b', 'a/03/b', 'a/04/b', 'a/05/b']],
     [
-      'a{001..9}b',
-      ['a001b', 'a002b', 'a003b', 'a004b', 'a005b', 'a006b', 'a007b', 'a008b', 'a009b'],
+      'a/{0..10..5}/b',
+      ['a/0/b', 'a/5/b', 'a/10/b'],
+      ['a/{10..0..5}/b', ['a/10/b', 'a/5/b', 'a/0/b']],
     ],
 
+    // Numeric range with padding (we do not support padding)
+    ['a/{00..05}/b', ['a/0/b', 'a/1/b', 'a/2/b', 'a/3/b', 'a/4/b', 'a/5/b']],
+    ['a{001..9}b', ['a1b', 'a2b', 'a3b', 'a4b', 'a5b', 'a6b', 'a7b', 'a8b', 'a9b']],
+
     // Numeric range with step
     ['a/{0..5..2}/b', ['a/0/b', 'a/2/b', 'a/4/b']],
     [

packages/tailwindcss/src/utils/brace-expansion.ts

@@ -72,9 +72,6 @@ function expandSequence(seq: string): string[] {
     let startNum = parseInt(start, 10)
     let endNum = parseInt(end, 10)
 
-    // Determine padding length (if any) but don't count the sign as length
-    let padLength = Math.max(start.replace(/^-/, '').length, end.replace(/^-/, '').length)
-
     if (step === undefined) {
       step = startNum <= endNum ? 1 : -1
     }
@@ -84,17 +81,11 @@ function expandSequence(seq: string): string[] {
     if (step > 0) {
       for (let i = startNum; i <= endNum; i += step) {
         let numStr = i.toString()
-        if (numStr.length < padLength) {
-          numStr = numStr.padStart(padLength, '0')
-        }
         result.push(numStr)
       }
     } else {
       for (let i = startNum; i >= endNum; i += step) {
         let numStr = i.toString()
-        if (numStr.length < padLength) {
-          numStr = numStr.padStart(padLength, '0')
-        }
         result.push(numStr)
       }
     }