Merge pull request #247 from Syuparn/fix-evalenv

di: fix Str#evalEnv to handle built-in objests

di/readnative.go

@@ -47,7 +47,7 @@ func readNativeCode(
 		return nil, e
 	}
 	if obj.Pairs == nil {
-		return nil, errors.New("Pairs must not be nil")
+		return nil, errors.New("pairs must not be nil")
 	}
 
 	return obj.Pairs, nil

di/strevalenv.go

@@ -7,7 +7,7 @@ import (
 )
 
 func strEvalEnv(
-	_ *object.Env,
+	env *object.Env,
 	kwargs *object.PanObj,
 	args ...object.PanObject,
 ) object.PanObject {
@@ -20,11 +20,12 @@ func strEvalEnv(
 		return object.NewTypeErr("\\1 must be str")
 	}
 
-	env := object.NewEnv()
-	result := eval(strings.NewReader(self.Value), env)
+	// NOTE: object.NewEnv cannot be used because an empty env does not have built-in objects
+	newEnv := object.NewEnclosedEnv(env.Global())
+	result := eval(strings.NewReader(self.Value), newEnv)
 	if result.Type() == object.ErrType {
 		return result
 	}
 
-	return env.Items()
+	return newEnv.Items()
 }

di/strevalenv_test.go

@@ -40,6 +40,15 @@ func TestEvalStrEvalEnv(t *testing.T) {
 				},
 			}),
 		},
+		{
+			`"x := true".evalEnv`,
+			toPanObj([]object.Pair{
+				{
+					Key:   object.NewPanStr("x"),
+					Value: object.BuiltInTrue,
+				},
+			}),
+		},
 	}
 
 	for _, tt := range tests {

object/env.go

@@ -124,6 +124,18 @@ func (e *Env) Outer() *Env {
 	return e.outer
 }
 
+// Global returns the outer environment.
+func (e *Env) Global() *Env {
+	env := e
+	for {
+		outer := env.Outer()
+		if outer == nil {
+			return env
+		}
+		env = outer
+	}
+}
+
 // InjectIO injects reader and writer for `IO` object
 func (e *Env) InjectIO(in io.Reader, out io.Writer) {
 	// define const `IO` containing io of args

object/env_test.go

@@ -189,3 +189,15 @@ func TestGetInOuter(t *testing.T) {
 			obj.Inspect(), found.Inspect())
 	}
 }
+
+func TestEnvGlobal(t *testing.T) {
+	parent := NewEnv()
+	child := NewEnclosedEnv(parent)
+	grandChild := NewEnclosedEnv(child)
+
+	actual := grandChild.Global()
+	if actual != parent {
+		t.Errorf("wrong env. expected=%+v, got=%+v",
+			parent, actual)
+	}
+}