blogposts: add the first test

blogposts/blogposts.go

@@ -0,0 +1,12 @@
+package blogposts
+
+import "io/fs"
+
+type Post struct {
+	Title, Description, Body string
+	Tags                     []string
+}
+
+func NewPostsFromFS(fs fs.FS) []Post {
+	return []Post{{}, {}}
+}

blogposts/blogposts_test.go

@@ -0,0 +1,20 @@
+package blogposts
+
+import (
+	"testing"
+	"testing/fstest"
+)
+
+// NOTE: This should be a black box test outside blogposts package.
+
+func TestNewBlogPosts(t *testing.T) {
+	fs := fstest.MapFS{
+		"hello world.md":  {Data: []byte("hi")},
+		"hello-world2.md": {Data: []byte("hola")},
+	}
+
+	posts := NewPostsFromFS(fs)
+	if len(posts) != len(fs) {
+		t.Errorf("got %d posts, wanted %d posts", len(posts), len(fs))
+	}
+}

blogposts/hello_world.md

@@ -0,0 +1,7 @@
+Title: Hello, TDD world!
+Description: First post on our wonderful blog
+Tags: tdd, go
+---
+Hello world!
+
+The body of posts starts after the `---`