MetricParameter: allow text with 0 decimal places

modules/plugin/chowdsp_parameters/ParamUtils/chowdsp_MetricParameter.cpp

@@ -41,41 +41,62 @@
 juce::String MetricParameter::toString (float value, int numDecimalPlaces)
 {
     const auto absValue = std::abs (value);
+    float valueInRange { value };
+    juce::String suffix {};
+
     if (absValue < 1.0e-12f) // femto
     {
-        return juce::String { value * 1.0e15f, numDecimalPlaces } + " f";
+        valueInRange = value * 1.0e15f;
+        suffix = " f";
     }
-    if (absValue < 1.0e-9f) // pico
+    else if (absValue < 1.0e-9f) // pico
     {
-        return juce::String { value * 1.0e12f, numDecimalPlaces } + " p";
+        valueInRange = value * 1.0e12f;
+        suffix = " p";
     }
-    if (absValue < 1.0e-6f) // nano
+    else if (absValue < 1.0e-6f) // nano
     {
-        return juce::String { value * 1.0e9f, numDecimalPlaces } + " n";
+        valueInRange = value * 1.0e9f;
+        suffix = " n";
     }
-    if (absValue < 1.0e-3f) // micro
+    else if (absValue < 1.0e-3f) // micro
     {
-        return juce::String { value * 1.0e6f, numDecimalPlaces } + " μ";
+        valueInRange = value * 1.0e6f;
+        suffix = juce::String::fromUTF8 (" μ");
     }
-    if (absValue < 1.0f) // milli
+    else if (absValue < 1.0f) // milli
     {
-        return juce::String { value * 1.0e3f, numDecimalPlaces } + " m";
+        valueInRange = value * 1.0e3f;
+        suffix = " m";
     }
-    if (absValue < 1.0e3f) // units
+    else if (absValue < 1.0e3f) // units
     {
-        return juce::String { value, numDecimalPlaces } + " ";
+        suffix = " ";
     }
-    if (absValue < 1.0e6f) // kilo
+    else if (absValue < 1.0e6f) // kilo
     {
-        return juce::String { value * 1.0e-3f, numDecimalPlaces } + " k";
+        valueInRange = value * 1.0e-3f;
+        suffix = " k";
     }
-    if (absValue < 1.0e9f) // mega
+    else if (absValue < 1.0e9f) // mega
     {
-        return juce::String { value * 1.0e-6f, numDecimalPlaces } + " M";
+        valueInRange = value * 1.0e-6f;
+        suffix = " M";
     }
+    else // Giga
+    {
+        valueInRange = value * 1.0e-9f;
+        suffix = " G";
+    }
+
+    juce::String res;
+    if (numDecimalPlaces == 0)
+        res = juce::String { static_cast<int> (valueInRange) };
+    else
+        res = juce::String { valueInRange, numDecimalPlaces };
+    res += suffix;
 
-    // Giga
-    return juce::String { value * 1.0e-9f, numDecimalPlaces } + " G";
+    return res;
 }
 
 float MetricParameter::fromString (const juce::String& str)

tests/plugin_tests/chowdsp_parameters_test/MetricParameterTest.cpp

@@ -113,4 +113,38 @@ TEST_CASE ("Metric Parameter Test", "[plugin][parameters]")
         REQUIRE (param.getCurrentValueAsText() == juce::String::fromUTF8 ("-1.00 mV"));
         REQUIRE (getValueForText() == Catch::Approx { param.get() }.margin (1.0e-6));
     }
+
+    SECTION ("Decimal Places")
+    {
+        static constexpr auto test_val = 1.54321f;
+        static constexpr auto test_val_milli = 1.54321e-3f;
+        std::array<std::tuple<int, std::string_view, std::string_view>, 5> tests {
+            std::tuple<int, std::string_view, std::string_view> { 4, "1.5432 V", "1.5432 mV" },
+            { 3, "1.543 V", "1.543 mV" },
+            { 2, "1.54 V", "1.54 mV" },
+            { 1, "1.5 V", "1.5 mV" },
+            { 0, "1 V", "1 mV" },
+        };
+
+        for (auto [num_decimals, test_str, test_str_milli] : tests)
+        {
+            chowdsp::MetricParameter param {
+                "param",
+                "Param",
+                juce::NormalisableRange { -2.0f, 2.0f },
+                0.0f,
+                juce::String::fromUTF8 ("V"),
+                num_decimals,
+            };
+
+            param.setParameterValue (test_val);
+            REQUIRE (param.getCurrentValueAsText() == chowdsp::toString (test_str));
+
+            if (num_decimals < 4)
+            {
+                param.setParameterValue (test_val_milli);
+                REQUIRE (param.getCurrentValueAsText() == chowdsp::toString (test_str_milli));
+            }
+        }
+    }
 }