From ec16fc9218ca16fc39cb7c68280ea6311f9d0805 Mon Sep 17 00:00:00 2001
From: Josh Micich <josh@apache.org>
Date: Fri, 22 May 2009 06:25:58 +0000
Subject: [PATCH] Bugzilla 47198 - Fixed formula evaluator comparison of -0.0
 and 0.0

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@777392 13f79535-47bb-0310-9956-ffa450edef68
---
 src/documentation/content/xdocs/changes.xml        |  1 +
 src/documentation/content/xdocs/status.xml         |  1 +
 .../formula/eval/RelationalOperationEval.java      |  4 ++++
 .../hssf/record/formula/eval/TestEqualEval.java    | 14 ++++++++++++++
 4 files changed, 20 insertions(+)

diff --git a/src/documentation/content/xdocs/changes.xml b/src/documentation/content/xdocs/changes.xml
index 4411ea6f6e..2549d2c287 100644
--- a/src/documentation/content/xdocs/changes.xml
+++ b/src/documentation/content/xdocs/changes.xml
@@ -37,6 +37,7 @@
 
 		<!-- Don't forget to update status.xml too! -->
         <release version="3.5-beta6" date="2009-??-??">
+           <action dev="POI-DEVELOPERS" type="add">47198 - Fixed formula evaluator comparison of -0.0 and 0.0</action>
            <action dev="POI-DEVELOPERS" type="add">47229 - Fixed ExternalNameRecord to handle DDE links</action>
            <action dev="POI-DEVELOPERS" type="add">46287 - Control of header and footer extraction in ExcelExtractor / XSSFExcelExtractor</action>
            <action dev="POI-DEVELOPERS" type="add">46554 - New ant target "jar-examples"</action>
diff --git a/src/documentation/content/xdocs/status.xml b/src/documentation/content/xdocs/status.xml
index b46e086a67..5486266da6 100644
--- a/src/documentation/content/xdocs/status.xml
+++ b/src/documentation/content/xdocs/status.xml
@@ -34,6 +34,7 @@
 	<!-- Don't forget to update changes.xml too! -->
     <changes>
         <release version="3.5-beta6" date="2009-??-??">
+           <action dev="POI-DEVELOPERS" type="add">47198 - Fixed formula evaluator comparison of -0.0 and 0.0</action>
            <action dev="POI-DEVELOPERS" type="add">47229 - Fixed ExternalNameRecord to handle DDE links</action>
            <action dev="POI-DEVELOPERS" type="add">46287 - Control of header and footer extraction in ExcelExtractor / XSSFExcelExtractor</action>
            <action dev="POI-DEVELOPERS" type="add">46554 - New ant target "jar-examples"</action>
diff --git a/src/java/org/apache/poi/hssf/record/formula/eval/RelationalOperationEval.java b/src/java/org/apache/poi/hssf/record/formula/eval/RelationalOperationEval.java
index 9dee4bc1e0..d5eef3e265 100644
--- a/src/java/org/apache/poi/hssf/record/formula/eval/RelationalOperationEval.java
+++ b/src/java/org/apache/poi/hssf/record/formula/eval/RelationalOperationEval.java
@@ -108,6 +108,10 @@ public abstract class RelationalOperationEval implements OperationEval {
 			if (vb instanceof NumberEval) {
 				NumberEval nA = (NumberEval) va;
 				NumberEval nB = (NumberEval) vb;
+				if (nA.getNumberValue() == nB.getNumberValue()) {
+					// Excel considers -0.0 == 0.0 which is different to Double.compare()
+					return 0;
+				}
 				return Double.compare(nA.getNumberValue(), nB.getNumberValue());
 			}
 		}
diff --git a/src/testcases/org/apache/poi/hssf/record/formula/eval/TestEqualEval.java b/src/testcases/org/apache/poi/hssf/record/formula/eval/TestEqualEval.java
index 3a027bb2e9..3053660b70 100644
--- a/src/testcases/org/apache/poi/hssf/record/formula/eval/TestEqualEval.java
+++ b/src/testcases/org/apache/poi/hssf/record/formula/eval/TestEqualEval.java
@@ -91,4 +91,18 @@ public final class TestEqualEval extends TestCase {
 		BoolEval be = (BoolEval) result;
 		return be.getBooleanValue();
 	}
+
+	/**
+	 * Excel considers -0.0 to be equal to 0.0
+	 */
+	public void testZeroEquality_bug47198() {
+		NumberEval zero = new NumberEval(0.0);
+		NumberEval mZero = (NumberEval) UnaryMinusEval.instance.evaluate(new Eval[] { zero, }, 0,
+				(short) 0);
+		Eval[] args = { zero, mZero, };
+		BoolEval result = (BoolEval) EqualEval.instance.evaluate(args, 0, (short) 0);
+		if (!result.getBooleanValue()) {
+			throw new AssertionFailedError("Identified bug 47198: -0.0 != 0.0");
+		}
+	}
 }
-- 
2.39.5