diff --git a/test/api/test-buffer.c b/test/api/test-buffer.c
index 64ab3db..228f0f3 100644
--- a/test/api/test-buffer.c
+++ b/test/api/test-buffer.c
@@ -208,7 +208,7 @@
       if (buffer_type == BUFFER_UTF16)
 	cluster++;
       else if (buffer_type == BUFFER_UTF8)
-        cluster += 3;
+	cluster += 3;
     }
     g_assert_cmphex (glyphs[i].codepoint, ==, utf32[1+i]);
     g_assert_cmphex (glyphs[i].cluster,   ==, cluster);