Fix broken lexer test

src/lexer.js

   scan(source) {
     let pos = 0
     let line = 1
-    let tokens = new TokenStream()
+    let tokenStream = new TokenStream()
 
     while (pos < source.length) {
       if (source[pos].match(/\(/)) {
-        tokens.push({
+        tokenStream.tokens.push({
           type: tokenTypes.OPAREN,
           line: line,
         })
         pos++
       } else if (source[pos].match(/\)/)) {
-        tokens.push({
+        tokenStream.tokens.push({
           type: tokenTypes.CPAREN,
           line: line,
         })
         pos++
       } else if (source[pos].match(/['"]/)) {
-        tokens.push({
+        tokenStream.tokens.push({
           type: tokenTypes.QUOTE,
           line: line,
         })
         pos++
       } else if (source[pos].match(/:/)) {
         let value = /:([^()'"\s]+)/.exec(source.slice(pos))[1].trim()
-        tokens.push({
+        tokenStream.tokens.push({
           type: tokenTypes.ATTRIBUTE,
           line: line,
           value: value,
         pos++
       } else {
         let value = /[^()"':]+/.exec(source.slice(pos))[0]
-        tokens.push({
+        tokenStream.tokens.push({
           type: tokenTypes.LITERAL,
           line: line,
           value: value.trim(),
       }
     }
 
-    tokens.push({
+    tokenStream.tokens.push({
       type: tokenTypes.EOF,
       line: line,
     })
-    return tokens
+    return tokenStream
   }
 }

src/tokenStream.js

 module.exports = class TokenStream extends Array {
   constructor() {
     super()
+    this.tokens = []
     this.position = 0
   }
 
   }
 
   peek(step = 0) {
-    return this[this.position + step]
+    return this.tokens[this.position + step]
   }
 }

test/lexer.js

   const lexer = new Lexer()
   let tokens = lexer.scan(
     '(div :class "foobar" (p "Lorem ipsum dolor sit amet"))',
-  )
+  ).tokens
   t.deepEqual(tokens.map(token => token.type), [
     tt.OPAREN,
     tt.LITERAL,
   let tokens = lexer.scan(`(
     (div :class "foobar"
       (p :class "bazquux"))
-  `)
+  `).tokens
   t.equal(tokens[2].line, 2)
   t.equal(tokens[7].line, 3)
 })