diff --git a/src/Makefile.am b/src/Makefile.am
index dd039300c..f2e7a3a9d 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -457,6 +457,7 @@ COMPILED_TESTS = \
 	test-repacker \
 	test-classdef-graph \
 	test-instancer-solver \
+	test-decompile-tuple-varstore \
 	$(NULL)
 COMPILED_TESTS_CPPFLAGS = $(HBCFLAGS) -DMAIN -UNDEBUG
 COMPILED_TESTS_LDADD = libharfbuzz.la $(HBLIBS)
@@ -531,6 +532,10 @@ test_instancer_solver_SOURCES = test-subset-instancer-solver.cc hb-subset-instan
 test_instancer_solver_CPPFLAGS = $(COMPILED_TESTS_CPPFLAGS)
 test_instancer_solver_LDADD = $(COMPILED_TESTS_LDADD)
 
+test_decompile_tuple_varstore_SOURCES = test-decompile-tuple-varstore.cc hb-static.cc
+test_decompile_tuple_varstore_CPPFLAGS = $(COMPILED_TESTS_CPPFLAGS)
+test_decompile_tuple_varstore_LDADD = $(COMPILED_TESTS_LDADD)
+
 dist_check_SCRIPTS = \
 	check-c-linkage-decls.py \
 	check-externs.py \
diff --git a/src/meson.build b/src/meson.build
index 539d92495..6f10612d3 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -723,6 +723,7 @@ if get_option('tests').enabled()
     'test-vector': ['test-vector.cc', 'hb-static.cc'],
     'test-bimap': ['test-bimap.cc', 'hb-static.cc'],
     'test-instancer-solver': ['test-subset-instancer-solver.cc', 'hb-subset-instancer-solver.cc', 'hb-static.cc'],
+    'test-decompile-tuple-varstore': ['test-decompile-tuple-varstore.cc', 'hb-static.cc'],
   }
   foreach name, source : compiled_tests
     if cpp.get_argument_syntax() == 'msvc' and source.contains('hb-static.cc')
diff --git a/src/test-decompile-tuple-varstore.cc b/src/test-decompile-tuple-varstore.cc
new file mode 100644
index 000000000..569189677
--- /dev/null
+++ b/src/test-decompile-tuple-varstore.cc
@@ -0,0 +1,79 @@
+/*
+ * Copyright © 2020  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ */
+#include "hb-ot-var-cvar-table.hh"
+
+// cvar table data from Multi-ABC.ttf
+const char cvar_data[] = "\x0\x1\x0\x0\x0\x2\x0\x14\x0\x51\xa0\x0\xc0\x0\x0\x54\xa0\x0\x40\x0\x2a\x29\x17\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\xd\xff\x0\xfd\x1\x0\xff\x0\xfd\x1\x0\xdb\xdb\xe6\xe6\x82\x0\xfd\x84\x6\xfd\x0\x2\xe3\xe3\xec\xec\x82\x4\x1\xe3\xe3\xec\xec\x82\x0\x1\x2a\x29\x17\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\x1\xd\x1\x0\x5\xfd\x0\x1\x0\x5\xfd\x0\x61\x61\x44\x44\x82\x0\x5\x81\x9\x1\xff\x1\x7\xff\xfb\x49\x49\x35\x35\x82\x4\xff\x49\x49\x35\x35\x82\x0\xff";
+
+static void
+test_decompile_cvar ()
+{
+  const OT::cvar* cvar_table = reinterpret_cast<const OT::cvar*> (cvar_data);
+  unsigned point_count = 65;
+  unsigned axis_count = 1;
+  OT::TupleVariationData::tuple_variations_t tuple_variations;
+  bool result = cvar_table->decompile_tuple_variations (axis_count, point_count, false, tuple_variations);
+  assert (result);
+  assert (tuple_variations.tuple_vars.length == 2);
+  for (unsigned i = 0; i < 2; i++)
+  {
+    assert (tuple_variations.tuple_vars[i].axis_tuples.get_population () == 1);
+    assert (!tuple_variations.tuple_vars[i].deltas_y);
+    assert (tuple_variations.tuple_vars[i].indices.length == 65);
+    assert (tuple_variations.tuple_vars[i].indices.length == tuple_variations.tuple_vars[i].deltas_x.length);
+  }
+  assert (tuple_variations.tuple_vars[0].axis_tuples.get (0) == Triple (-1.f, -1.f, 0.f));
+  assert (tuple_variations.tuple_vars[1].axis_tuples.get (0) == Triple (0.f, 1.f, 1.f));
+  
+  hb_vector_t<float> deltas_1 {0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, -1.f, 0.f, -3.f, 1.f, 0.f, -1.f, 0.f, -3.f, 1.f, 0.f, -37.f, -37.f, -26.f, -26.f, 0.f, 0.f, 0.f, -3.f, 0.f, 0.f, 0.f, 0.f, 0.f, -3.f, 0.f, 2.f, -29.f, -29.f, -20.f, -20.f, 0.f, 0.f, 0.f, 1.f, -29.f, -29.f, -20.f, -20.f, 0.f, 0.f, 0.f, 1.f};
+  for (unsigned i = 0; i < 65; i++)
+  {
+    if (i < 23)
+      assert (tuple_variations.tuple_vars[0].indices[i] == 0);
+    else
+    {
+      assert (tuple_variations.tuple_vars[0].indices[i] == 1);
+      assert (tuple_variations.tuple_vars[0].deltas_x[i] == deltas_1[i]);
+    }
+  }
+
+  hb_vector_t<float> deltas_2 {0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 0.f, 1.f, 0.f, 5.f, -3.f, 0.f, 1.f, 0.f, 5.f, -3.f, 0.f, 97.f, 97.f, 68.f, 68.f, 0.f, 0.f, 0.f, 5.f, 0.f, 0.f, 1.f, -1.f, 1.f, 7.f, -1.f, -5.f, 73.f, 73.f, 53.f, 53.f, 0.f, 0.f, 0.f, -1.f, 73.f, 73.f, 53.f, 53.f, 0.f, 0.f, 0.f, -1.f};
+  for (unsigned i = 0 ; i < 65; i++)
+  {
+    if (i < 23)
+      assert (tuple_variations.tuple_vars[1].indices[i] == 0);
+    else
+    {
+      assert (tuple_variations.tuple_vars[1].indices[i] == 1);
+      assert (tuple_variations.tuple_vars[1].deltas_x[i] == deltas_2[i]);
+    }
+  }
+}
+
+int
+main (int argc, char **argv)
+{
+  test_decompile_cvar ();
+}