feat: Access array item by negative index, closes #486

test/e2e/issues.ts

@@ -227,4 +227,9 @@ describe('Issues', function () {
     const html = await engine.parseAndRender(`{{ foo | concat | json }}`)
     expect(html).to.equal('[]')
   })
+  it('#486 Access array items from the right with negative indexes', async () => {
+    const engine = new Liquid()
+    const html = await engine.parseAndRender(`{% assign a = "x,y,z" | split: ',' -%}{{ a[-1] }} {{ a[-3] }} {{ a[-8] }}`)
+    expect(html).to.equal('z x ')
+  })
 })

test/unit/context/context.ts

@@ -22,7 +22,8 @@ describe('Context', function () {
         zoo: 'coo',
         'Mr.Smith': 'John',
         arr: ['a', 'b']
-      }
+      },
+      arr: ['a', 'b', 'c', 'd']
     }
     ctx = new Context(scope)
   })
@@ -69,6 +70,12 @@ describe('Context', function () {
     it('should read .last of array', async function () {
       expect(ctx.get(['bar', 'arr', 'last'])).to.equal('b')
     })
+    it('should read element of array', async function () {
+      expect(ctx.get(['arr', 1])).to.equal('b')
+    })
+    it('should read element of array from end', async function () {
+      expect(ctx.get(['arr', -2])).to.equal('c')
+    })
     it('should call function', async function () {
       expect(ctx.get(['func'])).to.equal('FUNC')
     })