Problem: coverage is not calculated correctly.

Solution: add dummy tests to packages w/o tests.

.codecov.yml

@@ -1,2 +1,2 @@
 coverage:
-  range: "75...85"
+  range: "55...70"

Makefile

@@ -18,8 +18,11 @@ install:
 
 test: install
 	go build -v -tags gofuzz ./...
+	go test -v ./tokens
 	go test -v ./scanner
+	go test -v ./ast
 	go test -v ./parser
+	go test -v ./objects
 	go test -v ./interpreter
 	go test -v -covermode=count -coverprofile=cover.out ./...
 

ast/ast_test.go

@@ -0,0 +1,17 @@
+// Gosh programming language.
+// Copyright (c) 2018 Alexey Palazhchenko and contributors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package ast
+
+import (
+	"testing"
+)
+
+// This dummy test exists for correct test coverage calculations.
+// Remove it when real tests are added.
+func TestDummy(t *testing.T) {
+}

objects/objects_test.go

@@ -0,0 +1,17 @@
+// Gosh programming language.
+// Copyright (c) 2018 Alexey Palazhchenko and contributors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package objects
+
+import (
+	"testing"
+)
+
+// This dummy test exists for correct test coverage calculations.
+// Remove it when real tests are added.
+func TestDummy(t *testing.T) {
+}

tokens/tokens_test.go

@@ -0,0 +1,17 @@
+// Gosh programming language.
+// Copyright (c) 2018 Alexey Palazhchenko and contributors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package tokens
+
+import (
+	"testing"
+)
+
+// This dummy test exists for correct test coverage calculations.
+// Remove it when real tests are added.
+func TestDummy(t *testing.T) {
+}