sanity check for StepModelFit.setSteps

psi · psi · commit 99b0c6218b2f · 2017-02-25T14:08:17.000+01:00
added unit test for StepModelFit
diff --git a/androidplot-core/src/main/java/com/androidplot/xy/StepModelFit.java b/androidplot-core/src/main/java/com/androidplot/xy/StepModelFit.java
@@ -2,6 +2,8 @@
 
 import com.androidplot.Region;
 
+import java.util.Arrays;
+
 /**
  * Subclass of StepModel that chooses from predefined step values. Depending on the currently
  * displayed range (by value) choose increment so that the number of lines
@@ -24,6 +26,16 @@ public double[] getSteps() {
     }
 
     public void setSteps(double[] steps) {
+
+        // sanity checks: no null, 0 or negative
+        if (steps == null || steps.length == 0)
+            return;
+
+        for (double step : steps) {
+            if (step <= 0.0d)
+                return;
+        }
+
         this.steps = steps;
     }
 
@@ -39,8 +51,9 @@ public void setScale(Region scale) {
     @Override
     public double getValue() {
 
-        // no possible increments where supplied (e.g. switched into this mode without calling setSteps(...)
-        if (steps == null)
+        // no possible increments where supplied
+        // or no region defined
+        if (steps == null || scale == null || !scale.isDefined())
             return super.getValue();
 
         double curStep = steps[0];
@@ -60,4 +73,13 @@ public double getValue() {
         }
         return curStep;
     }
+
+    @Override
+    public String toString() {
+        return "StepModelFit{" +
+                "steps=" + Arrays.toString(steps) +
+                ", scale=" + scale +
+                ", current stepping=" + getValue() +
+                '}';
+    }
 }
diff --git a/androidplot-core/src/test/java/com/androidplot/xy/StepModelFitTest.java b/androidplot-core/src/test/java/com/androidplot/xy/StepModelFitTest.java
@@ -0,0 +1,61 @@
+package com.androidplot.xy;
+
+import com.androidplot.Region;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+public class StepModelFitTest {
+
+    Region regionSmall = new Region(0,11);
+    Region regionBig = new Region(-111,420);
+    Region regionZero = new Region(0, 0);
+    Region regionUndef = new Region(0, null);
+
+    double[] stpSmall = {1,2,5}, stpBig = {1,10,100}, nonsense = {0};
+
+    @Before
+    public void setUp() throws Exception {
+
+    }
+
+    @After
+    public void tearDown() throws Exception {
+
+    }
+
+    @Test
+    public void getValue() throws Exception {
+
+        StepModelFit model = new StepModelFit(regionSmall,stpSmall,3);
+
+        assertEquals(5.0, model.getValue(), 0.0);
+        model.setValue(5.0);
+        assertEquals(2.0, model.getValue(), 0.0);
+        model.setValue(7.0);
+        assertEquals(2.0, model.getValue(), 0.0);
+
+        model.setSteps(stpBig);
+        assertEquals(1.0, model.getValue(), 0.0);
+
+        model.setScale(regionBig);
+        assertEquals(100.0, model.getValue(), 0.0);
+        model.setValue(1000.0);
+        assertEquals(1.0, model.getValue(), 0.0);
+
+        // bad parameters
+        model.setSteps(nonsense);
+        assertArrayEquals(stpBig,model.getSteps(), 0.0);
+
+        model.setScale(regionZero);
+        assertEquals(stpBig[0], model.getValue(), 0.0);
+
+        model.setScale(regionUndef);
+        model.setValue(1.1);
+        assertEquals(1.1, model.getValue(), 0.0);
+    }
+
+}
