diff --git a/pkg/spec/module_test.go b/pkg/spec/module_test.go
new file mode 100644
index 0000000..df1dc87
--- /dev/null
+++ b/pkg/spec/module_test.go
@@ -0,0 +1,13 @@
+package spec
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNames(t *testing.T) {
+	result, err := CheckFile("./testdata/names.module.yaml")
+	assert.NoError(t, err)
+	assert.Equal(t, 0, len(result.Errors))
+}
diff --git a/pkg/spec/schema_test.go b/pkg/spec/schema_test.go
new file mode 100644
index 0000000..41d77fc
--- /dev/null
+++ b/pkg/spec/schema_test.go
@@ -0,0 +1,50 @@
+package spec
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetDocumentType(t *testing.T) {
+	tests := []struct {
+		name string
+		want DocumentType
+	}{
+		{
+			name: "demo.idl",
+			want: DocumentTypeModule,
+		},
+		{
+			name: "demo.module.yaml",
+			want: DocumentTypeModule,
+		},
+		{
+			name: "demo.module.json",
+			want: DocumentTypeModule,
+		},
+		{
+			name: "demo.solution.yaml",
+			want: DocumentTypeSolution,
+		},
+		{
+			name: "demo.solution.json",
+			want: DocumentTypeSolution,
+		},
+		{
+			name: "rules.yaml",
+			want: DocumentTypeRules,
+		},
+		{
+			name: "rules.json",
+			want: DocumentTypeRules,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := GetDocumentType(tt.name)
+			assert.NoError(t, err)
+			assert.Equal(t, tt.want, got)
+		})
+	}
+}
diff --git a/pkg/spec/testdata/names.module.yaml b/pkg/spec/testdata/names.module.yaml
new file mode 100644
index 0000000..6079d82
--- /dev/null
+++ b/pkg/spec/testdata/names.module.yaml
@@ -0,0 +1,21 @@
+name: M.M
+version: "1.0.0"
+interfaces:
+  - name: A
+  - name: A_A
+  - name: a
+  - name: a_a
+  - name: a1
+  - name: a_1
+  - name: Demo
+    properties:
+      - name: a
+        type: bool
+      - name: a_a
+        type: bool
+      - name: A_a
+        type: bool
+      - name: A_A
+        type: bool
+
+