From 792f992dfc5636543a976092c4f101acac5a92db Mon Sep 17 00:00:00 2001
From: ed <eddavies95@gmail.com>
Date: Mon, 25 Oct 2021 15:41:02 +0100
Subject: [PATCH] ADSR:  Fix bug when using applyEnvelopeToBuffer() with
 zero-length attack and decay

---
 modules/juce_audio_basics/utilities/juce_ADSR.h    |  1 +
 .../juce_audio_basics/utilities/juce_ADSR_test.cpp | 14 ++++++++++++++
 2 files changed, 15 insertions(+)

diff --git a/modules/juce_audio_basics/utilities/juce_ADSR.h b/modules/juce_audio_basics/utilities/juce_ADSR.h
index fb0d894233..52d47c8e90 100644
--- a/modules/juce_audio_basics/utilities/juce_ADSR.h
+++ b/modules/juce_audio_basics/utilities/juce_ADSR.h
@@ -124,6 +124,7 @@ public:
         }
         else
         {
+            envelopeVal = parameters.sustain;
             state = State::sustain;
         }
     }
diff --git a/modules/juce_audio_basics/utilities/juce_ADSR_test.cpp b/modules/juce_audio_basics/utilities/juce_ADSR_test.cpp
index 3f2770683c..deff93126f 100644
--- a/modules/juce_audio_basics/utilities/juce_ADSR_test.cpp
+++ b/modules/juce_audio_basics/utilities/juce_ADSR_test.cpp
@@ -152,6 +152,20 @@ struct ADSRTests  : public UnitTest
             expect (isSustained (buffer, parameters.sustain));
         }
 
+        beginTest ("Zero-length attack and decay releases correctly");
+        {
+            adsr.reset();
+            adsr.setParameters ({ 0.0f, 0.0f, parameters.sustain, parameters.release });
+
+            adsr.noteOn();
+            adsr.noteOff();
+
+            auto buffer = getTestBuffer (sampleRate, parameters.release);
+            adsr.applyEnvelopeToBuffer (buffer, 0, buffer.getNumSamples());
+
+            expect (isDecreasing (buffer));
+        }
+
         beginTest ("Zero-length release resets to idle");
         {
             adsr.reset();