test: add test for bom test data integrity

Signed-off-by: Thomas FREYSS <thomas.freyss@gmail.com>

pkg/chart/loader/load_test.go

@@ -20,6 +20,7 @@ import (
 	"archive/tar"
 	"bytes"
 	"compress/gzip"
+	"io"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -85,6 +86,54 @@ func TestLoadDirWithSymlink(t *testing.T) {
 	verifyDependenciesLock(t, c)
 }
 
+func TestBomTestData(t *testing.T) {
+	testFiles := []string{"frobnitz_with_bom/.helmignore", "frobnitz_with_bom/templates/template.tpl", "frobnitz_with_bom/Chart.yaml"}
+	for _, file := range testFiles {
+		data, err := ioutil.ReadFile("testdata/" + file)
+		if err != nil || !bytes.HasPrefix(data, utf8bom) {
+			t.Errorf("Test file has no BOM or is invalid: testdata/%s", file)
+		}
+	}
+
+	archive, err := ioutil.ReadFile("testdata/frobnitz_with_bom.tgz")
+	if err != nil {
+		t.Fatalf("Error reading archive frobnitz_with_bom.tgz: %s", err)
+	}
+	unzipped, err := gzip.NewReader(bytes.NewReader(archive))
+	if err != nil {
+		t.Fatalf("Error reading archive frobnitz_with_bom.tgz: %s", err)
+	}
+	defer unzipped.Close()
+	for _, testFile := range testFiles {
+		data := make([]byte, 3)
+		err := unzipped.Reset(bytes.NewReader(archive))
+		if err != nil {
+			t.Fatalf("Error reading archive frobnitz_with_bom.tgz: %s", err)
+		}
+		tr := tar.NewReader(unzipped)
+		for {
+			file, err := tr.Next()
+			if err == io.EOF {
+				break
+			}
+			if err != nil {
+				t.Fatalf("Error reading archive frobnitz_with_bom.tgz: %s", err)
+			}
+			if file != nil && strings.EqualFold(file.Name, testFile) {
+				_, err := tr.Read(data)
+				if err != nil {
+					t.Fatalf("Error reading archive frobnitz_with_bom.tgz: %s", err)
+				} else {
+					break
+				}
+			}
+		}
+		if !bytes.Equal(data, utf8bom) {
+			t.Fatalf("Test file has no BOM or is invalid: frobnitz_with_bom.tgz/%s", testFile)
+		}
+	}
+}
+
 func TestLoadDirWithUTFBOM(t *testing.T) {
 	l, err := Loader("testdata/frobnitz_with_bom")
 	if err != nil {