Pluginval can set an AudioParameterBools to odd values

I’m debugging a strange issue that sometimes leads to Pluginval’s state restoration test to fail. This is with an AU plugin, I’m not sure yet if it also happens with the VST3.

The test checks if the sum of parameter values is the same before and after a state restore. Under some circumstances, when the test starts, the two AudioParameterBools that the plugin uses have random values that are not 0.f or 1.f. After saving and restoring the state they are correctly set to either 0.f or 1.f, and thus the test fails because of the difference.

Whether the test fails depends mainly on which other tests have run before. There seem to be several tests that somehow manage to produce these odd parameter values.

Anyone ran into this problem before? I think it normally shouldn’t be possible at all to set AudioParameterBools to such odd values, especially from the outside.

This is on JUCE 6.1.6.

Tracked the issue down further, and on develop it’s the same. AudioParameterBool can just be set to any float value. I’d propose the following change to fix it. That should somewhat guarantee non-surprising values for bool parameters.

diff --git a/modules/juce_audio_processors/utilities/juce_AudioParameterBool.cpp b/modules/juce_audio_processors/utilities/juce_AudioParameterBool.cpp
index 4ba512ddd..9d42b6ef7 100644
--- a/modules/juce_audio_processors/utilities/juce_AudioParameterBool.cpp
+++ b/modules/juce_audio_processors/utilities/juce_AudioParameterBool.cpp
@@ -77,7 +77,7 @@ AudioParameterBool::~AudioParameterBool()
 }
 
 float AudioParameterBool::getValue() const                               { return value; }
-void AudioParameterBool::setValue (float newValue)                       { value = newValue; valueChanged (get()); }
+void AudioParameterBool::setValue (float newValue)                       { value = newValue >= 0.5f; valueChanged (get()); }
 float AudioParameterBool::getDefaultValue() const                        { return defaultValue; }
 int AudioParameterBool::getNumSteps() const                              { return 2; }
 bool AudioParameterBool::isDiscrete() const                              { return true; }