fix: empty tagToken.args since 10.20.0, fixes #796

Author: harttle

src/tokens/tag-token.ts

@@ -5,6 +5,7 @@ import type { NormalizedFullOptions } from '../liquid-options'
 export class TagToken extends DelimitedToken {
   public name: string
   public tokenizer: Tokenizer
+  public readonly args: string;
   public constructor (
     input: string,
     begin: number,
@@ -20,9 +21,6 @@ export class TagToken extends DelimitedToken {
     this.name = this.tokenizer.readTagName()
     this.tokenizer.assert(this.name, `illegal tag syntax, tag name expected`)
     this.tokenizer.skipBlank()
-  }
-
-  get args (): string {
-    return this.tokenizer.input.slice(this.tokenizer.p, this.contentRange[1])
+    this.args = this.tokenizer.input.slice(this.tokenizer.p, this.contentRange[1])
   }
 }

test/e2e/issues.spec.ts

@@ -1,4 +1,4 @@
-import { TopLevelToken, TagToken, Tokenizer, Context, Liquid, Drop, toValueSync, LiquidError } from '../..'
+import { TopLevelToken, TagToken, Tokenizer, Context, Liquid, Drop, toValueSync, LiquidError, IfTag } from '../..'
 const LiquidUMD = require('../../dist/liquid.browser.umd.js').Liquid
 
 describe('Issues', function () {
@@ -558,4 +558,11 @@ describe('Issues', function () {
           CSharp <sup>2</sup> Posts:page2,page4,
           CPP <sup>1</sup> Posts:page0,`)
   })
+  it('if tag condition, the token args is empty #796', () => {
+    const tpl = 'Hello, {% if name  %} {{ name }} {% else %} user {% endif %}'
+    const engine = new Liquid()
+    const parsed = engine.parse(tpl)
+    const ifToken = parsed[1]
+    expect((ifToken as IfTag).token.args).toEqual('name')
+  })
 })