diff --git a/tests/test_index.c b/tests/test_index.c
index d195fc17..8ef5cb40 100644
--- a/tests/test_index.c
+++ b/tests/test_index.c
@@ -1622,6 +1622,53 @@ test_lzma_index_decoder(void)
 }
 
 
+static void
+test_lzma_index_decoder_memusage(void)
+{
+#ifndef HAVE_DECODERS
+	assert_skip("Decoder support disabled");
+#else
+	assert_uint(decode_buffer_size, >, 20);
+
+	lzma_stream strm = LZMA_STREAM_INIT;
+	lzma_index *idx = NULL;
+	assert_lzma_ret(lzma_index_decoder(&strm, &idx, MEMLIMIT), LZMA_OK);
+
+	// Nothing decoded yet.
+	assert_uint(lzma_memusage(&strm), <, 1000);
+
+	const size_t step = 5;
+	size_t remaining = decode_buffer_size;
+	strm.next_in = decode_buffer;
+	strm.avail_in = step;
+	remaining -= strm.avail_in;
+
+	uint64_t memused = 0;
+
+	while (true) {
+		lzma_ret ret = lzma_code(&strm, LZMA_RUN);
+		if (ret == LZMA_STREAM_END)
+			break;
+
+		assert_lzma_ret(ret, LZMA_OK);
+		assert_uint_eq(strm.avail_in, 0);
+		strm.avail_in = my_min(remaining, step);
+		remaining -= strm.avail_in;
+
+		if (memused == 0) {
+			memused = lzma_memusage(&strm);
+			assert_uint(memused, >, 100);
+		} else {
+			assert_uint_eq(lzma_memusage(&strm), memused);
+		}
+	}
+
+	lzma_index_end(idx, NULL);
+	lzma_end(&strm);
+#endif
+}
+
+
 static void
 test_lzma_index_buffer_encode(void)
 {
@@ -1831,6 +1878,7 @@ main(int argc, char **argv)
 	tuktest_run(test_lzma_index_dup);
 	tuktest_run(test_lzma_index_encoder);
 	tuktest_run(test_lzma_index_decoder);
+	tuktest_run(test_lzma_index_decoder_memusage);
 	tuktest_run(test_lzma_index_buffer_encode);
 	tuktest_run(test_lzma_index_buffer_decode);
 	tuktest_run(test_decode_empty_and_append);