1 files changed, 23 insertions, 1 deletions
diff --git a/evaluator/evaluator_test.go b/evaluator/evaluator_test.go
index 6553f55..38fed91 100644
--- a/evaluator/evaluator_test.go
+++ b/evaluator/evaluator_test.go
@@ -177,6 +177,10 @@ func TestErrorhandling(t *testing.T) {
       `,
       "unknown operator: BOOLEAN + BOOLEAN",
     },
+    {
+      "foobar",
+      "identifier not found: foobar",
+    },
   }
 
   for _, tt := range tests {
@@ -194,11 +198,29 @@ func TestErrorhandling(t *testing.T) {
   }
 }
 
+func TestLetStatements(t *testing.T) {
+  tests := []struct {
+    input string
+    expected int64
+  } {
+    {"let a = 5; a;", 5},
+    {"let a = 5 * 5; a;", 25},
+    {"let a = 5; let b = a; b;", 5},
+    {"let a = 5; let b = a; let c = a + b + 5; c;", 15},
+  }
+
+  for _, tt := range tests {
+    testIntegerObject(t, testEval(tt.input), tt.expected)
+  }
+}
+
 func testEval(input string) object.Object {
 	l := lexer.New(input)
 	p := parser.New(l)
 	program := p.ParseProgram()
-	return Eval(program)
+  env := object.NewEnvironment()
+
+	return Eval(program, env)
 }
 
 func testIntegerObject(t *testing.T, obj object.Object, expected int64) bool {