Propagate errors encountered when reading file

godotenv.go

@@ -143,6 +143,10 @@ func readFile(filename string) (envMap map[string]string, err error) {
 		lines = append(lines, scanner.Text())
 	}
 
+	if err = scanner.Err(); err != nil {
+		return
+	}
+
 	for _, fullLine := range lines {
 		if !isIgnoredLine(fullLine) {
 			key, value, err := parseLine(fullLine)

godotenv_test.go

@@ -269,3 +269,12 @@ func TestLinesToIgnore(t *testing.T) {
 		t.Error("ignoring a perfectly valid line to parse")
 	}
 }
+
+func TestErrorReadDirectory(t *testing.T) {
+	envFileName := "fixtures/"
+	envMap, err := Read(envFileName)
+
+	if err == nil {
+		t.Errorf("Expected error, got %v", envMap)
+	}
+}