Add tests for File

tfwrite/file.go

@@ -12,6 +12,12 @@ func NewFile(file *hclwrite.File) *File {
 	return &File{raw: file}
 }
 
+// NewEmptyFile creates a new file with an empty body.
+func NewEmptyFile() *File {
+	file := hclwrite.NewEmptyFile()
+	return NewFile(file)
+}
+
 // Raw returns a raw object for hclwrite.
 func (f *File) Raw() *hclwrite.File {
 	return f.raw

tfwrite/file_test.go

@@ -0,0 +1,91 @@
+package tfwrite
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func TestFileFindResourcesByType(t *testing.T) {
+	cases := []struct {
+		desc         string
+		src          string
+		resourceType string
+		want         string
+		ok           bool
+	}{
+		{
+			desc: "simple",
+			src: `
+resource "foo_test" "example1" {}
+resource "foo_test" "example2" {}
+resource "foo_bar" "example1" {}
+data "foo_test" "example1" {}
+`,
+			resourceType: "foo_test",
+			want: `
+resource "foo_test" "example1" {}
+
+resource "foo_test" "example2" {}
+`,
+			ok: true,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.desc, func(t *testing.T) {
+			f := parseTestFile(t, tc.src)
+			resources := f.FindResourcesByType(tc.resourceType)
+
+			newFile := NewEmptyFile()
+			for _, r := range resources {
+				newFile.AppendResource(r)
+			}
+
+			got := printTestFile(t, newFile)
+			if diff := cmp.Diff(got, tc.want); diff != "" {
+				t.Fatalf("got:\n%s\nwant:\n%s\ndiff:\n%s", got, tc.want, diff)
+			}
+		})
+	}
+}
+
+func TestFileAppendResource(t *testing.T) {
+	cases := []struct {
+		desc         string
+		src          string
+		resourceType string
+		resourceName string
+		want         string
+		ok           bool
+	}{
+		{
+			desc: "simple",
+			src: `
+resource "foo_test" "example1" {}
+`,
+			resourceType: "foo_test",
+			resourceName: "example2",
+			want: `
+resource "foo_test" "example1" {}
+
+resource "foo_test" "example2" {
+}
+`,
+			ok: true,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.desc, func(t *testing.T) {
+			f := parseTestFile(t, tc.src)
+			r := NewEmptyResource(tc.resourceType, tc.resourceName)
+			f.AppendResource(r)
+
+			got := printTestFile(t, f)
+			if diff := cmp.Diff(got, tc.want); diff != "" {
+				t.Fatalf("got:\n%s\nwant:\n%s\ndiff:\n%s", got, tc.want, diff)
+			}
+		})
+	}
+}