Test: add noise Wave generation testing

Refs: #9

tests/generators_test.cpp

@@ -33,3 +33,13 @@ TEST(Generator, InverseSawWave) {
   // Starts at 1
   EXPECT_EQ(t[0], 1);
 }
+
+TEST(Generator, NoiseWave)
+{
+  sample_table_t t = gen_noise();
+  // Always start and end at 0
+  EXPECT_EQ(t[0], 0);
+  EXPECT_EQ(t[DEFAULT_N_SAMPLES - 1], 0);
+  // Check second value, probably not equal to 0
+  EXPECT_NE(t[1], 0);
+}