plectrum

commit d0f249754303f8f025ca1cb0e5a9fc941bb5786c
parent 2f95909fed542502ee5fb58458410e98548e847c
Author: gstraube <gstraube@mailbox.org>
Date:   Sun, 23 Jul 2017 18:30:59 +0200

Add tests for sampler

Diffstat:
M
app/src/main/java/com/github/cythara/Sampler.java
 | 
2
+-
A
app/src/test/java/com/github/cythara/SamplerTest.java
 | 
66
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 67 insertions(+), 1 deletion(-)
diff --git a/app/src/main/java/com/github/cythara/Sampler.java b/app/src/main/java/com/github/cythara/Sampler.java
@@ -30,7 +30,7 @@ class Sampler {
     }
 
     @Nullable
-    private static Note extractMostFrequentNote(List<PitchDifference> samples) {
+    static Note extractMostFrequentNote(List<PitchDifference> samples) {
         Map<Note, Integer> noteFrequencies = new HashMap<>();
 
         for (PitchDifference pitchDifference : samples) {
diff --git a/app/src/test/java/com/github/cythara/SamplerTest.java b/app/src/test/java/com/github/cythara/SamplerTest.java
@@ -0,0 +1,65 @@
+package com.github.cythara;
+
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static com.github.cythara.Note.*;
+import static com.github.cythara.Sampler.*;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.Matchers.closeTo;
+import static org.junit.Assert.*;
+
+public class SamplerTest {
+
+    @Test
+    public void the_average_difference_is_calculated_correctly() {
+        List<PitchDifference> samples = new ArrayList<>();
+
+        samples.add(new PitchDifference(E2, 2.46D));
+        samples.add(new PitchDifference(E2, -10.3D));
+        samples.add(new PitchDifference(E2, 5.71D));
+        samples.add(new PitchDifference(E2, 12.532D));
+        samples.add(new PitchDifference(E2, -0.414D));
+
+        PitchDifference pitchDifference = calculateAverageDifference(samples);
+
+        double average = (2.46D - 10.3D + 5.71D + 12.532D - 0.414D) / 5D;
+
+        assertNotNull(pitchDifference);
+        assertThat(pitchDifference.closest, is(E2));
+        assertThat(pitchDifference.deviation, closeTo(average, 0.001));
+    }
+
+    @Test
+    public void the_most_frequent_note_is_extracted_correctly() throws Exception {
+        List<PitchDifference> samples = new ArrayList<>();
+
+        samples.add(new PitchDifference(E2, 2D));
+        samples.add(new PitchDifference(E2, 2D));
+        samples.add(new PitchDifference(B3, 3D));
+        samples.add(new PitchDifference(E2, 2D));
+        samples.add(new PitchDifference(Note.G3, 4D));
+        samples.add(new PitchDifference(B3, 3D));
+
+        Note note = extractMostFrequentNote(samples);
+
+        assertThat(note, is(E2));
+    }
+
+    @Test
+    public void if_there_are_notes_with_the_same_number_of_occurrences_the_first_one_is_returned() {
+        List<PitchDifference> samples = new ArrayList<>();
+
+        samples.add(new PitchDifference(G3, 2D));
+        samples.add(new PitchDifference(E2, 2D));
+        samples.add(new PitchDifference(B3, 3D));
+        samples.add(new PitchDifference(E2, 2D));
+        samples.add(new PitchDifference(B3, 3D));
+
+        Note note = extractMostFrequentNote(samples);
+
+        assertThat(note, is(E2));
+    }
+}
+\ No newline at end of file