fix: sort filter unexpectedly modifies original array, #475

Author: harttle

docs/themes/navy/layout/partial/all-contributors.swig

@@ -53,6 +53,8 @@
     <td align="center"><a href="https://www.aleksandrhovhannisyan.com/"><img src="https://avatars.githubusercontent.com/u/19352442?v=4?s=100" width="100px;" alt=""/></a></td>
     <td align="center"><a href="https://github.com/jg-rp"><img src="https://avatars.githubusercontent.com/u/72664870?v=4?s=100" width="100px;" alt=""/></a></td>
     <td align="center"><a href="https://github.com/ameyaapte1"><img src="https://avatars.githubusercontent.com/u/16054747?v=4?s=100" width="100px;" alt=""/></a></td>
+    <td align="center"><a href="https://github.com/tbdrz"><img src="https://avatars.githubusercontent.com/u/50599116?v=4?s=100" width="100px;" alt=""/></a></td>
+    <td align="center"><a href="http://santialbo.com"><img src="https://avatars.githubusercontent.com/u/1557563?v=4?s=100" width="100px;" alt=""/></a></td>
   </tr>
 </table>
 

src/builtin/filters/array.ts

@@ -12,7 +12,7 @@ export const reverse = (v: any[]) => [...v].reverse()
 
 export function sort<T> (this: FilterImpl, arr: T[], property?: string) {
   const getValue = (obj: Scope) => property ? this.context.getFromScope(obj, property.split('.')) : obj
-  return toArray(arr).sort((lhs, rhs) => {
+  return [...toArray(arr)].sort((lhs, rhs) => {
     lhs = getValue(lhs)
     rhs = getValue(rhs)
     return lhs < rhs ? -1 : (lhs > rhs ? 1 : 0)

src/template/output.ts

@@ -12,7 +12,7 @@ export class Output extends TemplateImpl<OutputToken> implements Template {
     super(token)
     this.value = new Value(token.content, liquid)
   }
-  public * render (ctx: Context, emitter: Emitter): Generator<unknown, void, unknown> {
+  public * render (ctx: Context, emitter: Emitter): IterableIterator<unknown> {
     const val = yield this.value.value(ctx, false)
     emitter.write(val)
   }

test/integration/builtin/filters/array.ts

@@ -138,6 +138,10 @@ describe('filters/array', function () {
       const c = { name: { first: 'Carol' } }
       return test(tpl, { arr: [b, c, a, c] }, 'Alice Bob Carol Carol')
     })
+    it('should not change the original array', () => {
+      const arr = ["one", "two", "three", "four", "five"]
+      return test("{{arr | sort}} {{arr}}", { arr }, 'fivefouronethreetwo onetwothreefourfive')
+    })
   })
   describe('uniq', function () {
     it('should uniq string list', function () {