diff --git a/plugin/storage/es/mappings/mapping_test.go b/plugin/storage/es/mappings/mapping_test.go
index 33cfb00e53c..1d0f4372fe5 100644
--- a/plugin/storage/es/mappings/mapping_test.go
+++ b/plugin/storage/es/mappings/mapping_test.go
@@ -80,6 +80,32 @@ func TestMappingBuilderGetMapping(t *testing.T) {
 	}
 }
 
+func TestMappingTypeFromString(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected MappingType
+		hasError bool
+	}{
+		{"jaeger-span", SpanMapping, false},
+		{"jaeger-service", ServiceMapping, false},
+		{"jaeger-dependencies", DependenciesMapping, false},
+		{"jaeger-sampling", SamplingMapping, false},
+		{"invalid", MappingType(-1), true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.input, func(t *testing.T) {
+			result, err := MappingTypeFromString(tt.input)
+			if tt.hasError {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				assert.Equal(t, tt.expected, result)
+			}
+		})
+	}
+}
+
 func TestMappingBuilderLoadMapping(t *testing.T) {
 	tests := []struct {
 		name string