X-Git-Url: https://gitweb.fperrin.net/?p=GpsPrune.git;a=blobdiff_plain;f=test%2Ftim%2Fprune%2Fjpeg%2Fdrew%2FRationalTest.java;fp=test%2Ftim%2Fprune%2Fjpeg%2Fdrew%2FRationalTest.java;h=ae97e0fdac79d0d2c2f52582660ab6a27f31964f;hp=0000000000000000000000000000000000000000;hb=cd5dd0c207b676067e85e0885b90f05445b7e229;hpb=1db53356139320890a8d10e982865a1899e11b81

diff --git a/test/tim/prune/jpeg/drew/RationalTest.java b/test/tim/prune/jpeg/drew/RationalTest.java
new file mode 100644
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+++ b/test/tim/prune/jpeg/drew/RationalTest.java
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+package tim.prune.jpeg.drew;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * JUnit tests for the Rational values used by the Exif
+ */
+class RationalTest
+{
+	@Test
+	void testManyInts()
+	{
+		testIntVal(0, 0, 0);
+		testIntVal(1, 0, 0);
+		testIntVal(0, 1, 0);
+		for (int i=0; i<16000; i++)
+		{
+			testIntVal(0, i, 0);
+			testIntVal(i, 0, 0);
+			testIntVal(i, 1, i);
+			testIntVal(-i, 1, -i);
+			testIntVal(i*2, 2, i);
+			testIntVal(i*2+1, 2, i);	// rounding down the 0.5
+			testIntVal(-i*2, 2, -i);
+			testIntVal(i*2, -2, -i);
+			testIntVal(-i*2, -2, i);
+		}
+	}
+
+	/**
+	 * Check that a rational converts to an integer properly
+	 * @param inTop number on top of the rational (numerator)
+	 * @param inBottom number on bottom of the rational (denominator)
+	 * @param inExpected expected int value
+	 */
+	private void testIntVal(long inTop, long inBottom, int inExpected)
+	{
+		Rational value = new Rational(inTop, inBottom);
+		assertEquals(inExpected, value.intValue(), "" + inTop + "/" + inBottom);
+	}
+
+	@Test
+	void testManyDoubles()
+	{
+		for (int i=0; i<16000; i++)
+		{
+			testDoubleVal(0, i, 0.0);
+			testDoubleVal(i, 0, 0.0);
+			testDoubleVal(i, 1, i);
+			testDoubleVal(i*2, 2, i);
+			testDoubleVal(i*2+1, 2, i+0.5);
+			testDoubleVal(i*2, -2, -i);
+		}
+
+		testDoubleVal(123, 3, 123.0/3.0);
+	}
+
+	/**
+	 * Check that a rational converts to a double properly
+	 * @param inTop number on top of the rational (numerator)
+	 * @param inBottom number on bottom of the rational (denominator)
+	 * @param inExpected expected double value (exact)
+	 */
+	private void testDoubleVal(long inTop, long inBottom, double inExpected)
+	{
+		Rational value = new Rational(inTop, inBottom);
+		assertEquals(inExpected, value.doubleValue(), 0.0, "" + inTop + "/" + inBottom);
+	}
+}