From fcde5a4621a29e9d15ee95ba34c0b3ac056a2c44 Mon Sep 17 00:00:00 2001
From: Travis Keep <keep94@gmail.com>
Date: Fri, 21 Feb 2014 20:41:39 +0000
Subject: [PATCH] ICU-10547 Format -0.0 as a negative when using scientific
 notation.

X-SVN-Rev: 35196
---
 icu4c/source/i18n/decimfmt.cpp          |  7 +++++++
 icu4c/source/test/intltest/numfmtst.cpp | 18 ++++++++++++++++++
 icu4c/source/test/intltest/numfmtst.h   |  3 ++-
 3 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/icu4c/source/i18n/decimfmt.cpp b/icu4c/source/i18n/decimfmt.cpp
index d6864dc6fa3..4ac3f640bb7 100644
--- a/icu4c/source/i18n/decimfmt.cpp
+++ b/icu4c/source/i18n/decimfmt.cpp
@@ -1643,6 +1643,13 @@ DecimalFormat::_round(const DigitList &number, DigitList &adjustedNum, UBool& is
         int32_t sigDigits = precision();
         if (sigDigits > 0) {
             adjustedNum.round(sigDigits);
+            // Travis Keep (21/2/2014): Calling round on a digitList does not necessarily
+            // preserve the sign of that digit list. Preserving the sign is especially
+            // important when formatting -0.0 for instance. Not preserving the sign seems
+            // like a bug because I cannot think of any case where the sign would actually
+            // have to change when rounding. For now, we preserve the sign by setting the
+            // positive attribute directly.
+            adjustedNum.setPositive(!isNegative);
         }
     } else {
         // Fixed point format.  Round to a set number of fraction digits.
diff --git a/icu4c/source/test/intltest/numfmtst.cpp b/icu4c/source/test/intltest/numfmtst.cpp
index a5c50108737..ab952ca39f7 100644
--- a/icu4c/source/test/intltest/numfmtst.cpp
+++ b/icu4c/source/test/intltest/numfmtst.cpp
@@ -131,6 +131,7 @@ void NumberFormatTest::runIndexedTest( int32_t index, UBool exec, const char* &n
   TESTCASE_AUTO(Test10419RoundingWith0FractionDigits);
   TESTCASE_AUTO(Test10468ApplyPattern);
   TESTCASE_AUTO(TestRoundingScientific10542);
+  TESTCASE_AUTO(TestZeroScientific10547);
   TESTCASE_AUTO_END;
 }
 
@@ -7539,6 +7540,23 @@ void NumberFormatTest::TestRoundingScientific10542() {
     }
 }
 
+void NumberFormatTest::TestZeroScientific10547() {
+    UErrorCode status = U_ZERO_ERROR;
+    {
+        DecimalFormat fmt("0.00", status);
+        UnicodeString out;
+        fmt.format(-0.0, out);
+        assertEquals("formatFixed", "-0.00", out);
+    }
+    DecimalFormat fmt("0.00E0", status);
+    if (!assertSuccess("Formt creation", status)) {
+        return;
+    }
+    UnicodeString out;
+    fmt.format(-0.0, out);
+    assertEquals("format", "-0.00E0", out);
+}
+
 void NumberFormatTest::verifyRounding(
         DecimalFormat& format,
         const double *values,
diff --git a/icu4c/source/test/intltest/numfmtst.h b/icu4c/source/test/intltest/numfmtst.h
index 28cf5a2d273..f220f20c708 100644
--- a/icu4c/source/test/intltest/numfmtst.h
+++ b/icu4c/source/test/intltest/numfmtst.h
@@ -1,6 +1,6 @@
 /************************************************************************
  * COPYRIGHT:
- * Copyright (c) 1997-2013, International Business Machines Corporation
+ * Copyright (c) 1997-2014, International Business Machines Corporation
  * and others. All Rights Reserved.
  ************************************************************************/
 
@@ -178,6 +178,7 @@ class NumberFormatTest: public CalendarTimeZoneTest {
     void Test10419RoundingWith0FractionDigits();
     void Test10468ApplyPattern();
     void TestRoundingScientific10542();
+    void TestZeroScientific10547();
 
  private:
     UBool testFormattableAsUFormattable(const char *file, int line, Formattable &f);
-- 
2.40.0