commit 4bc6ad328bbc1f1acc4b6efd5f37b3cca4713f1b
author Shane Carr <shane@unicode.org> Sat Jun 23 02:09:42 2018 +0000
committer Shane Carr <shane@unicode.org> Sat Jun 23 02:09:42 2018 +0000
tree 7c4bb0dd97ccbbbfdfd2c61fbcfe797aa6df0e72
parent f1d29ce62e25e8e182773e721e7b0946604511dc

ICU-13850 Fixing behavior of ICU4C DecimalFormat#setCurrency() to accept an empty string.

X-SVN-Rev: 41549

icu4c/source/i18n/currunit.cpp

diff --git a/icu4c/source/i18n/currunit.cpp b/icu4c/source/i18n/currunit.cpp
index 3de6856..bd60593 100644
--- a/icu4c/source/i18n/currunit.cpp
+++ b/icu4c/source/i18n/currunit.cpp
@@ -27,8 +27,9 @@
     // The constructor always leaves the CurrencyUnit in a valid state (with a 3-character currency code).
     // Note: in ICU4J Currency.getInstance(), we check string length for 3, but in ICU4C we allow a
     // non-NUL-terminated string to be passed as an argument, so it is not possible to check length.
+    // However, we allow a NUL-terminated empty string, which should have the same behavior as nullptr.
     const char16_t* isoCodeToUse;
-    if (U_FAILURE(ec) || _isoCode == nullptr) {
+    if (U_FAILURE(ec) || _isoCode == nullptr || _isoCode[0] == 0) {
         isoCodeToUse = kDefaultCurrency;
     } else if (!uprv_isInvariantUString(_isoCode, 3)) {
         // TODO: Perform a more strict ASCII check like in ICU4J isAlpha3Code?

icu4c/source/test/intltest/numfmtst.cpp

diff --git a/icu4c/source/test/intltest/numfmtst.cpp b/icu4c/source/test/intltest/numfmtst.cpp
index b718429..ffc1e83 100644
--- a/icu4c/source/test/intltest/numfmtst.cpp
+++ b/icu4c/source/test/intltest/numfmtst.cpp
@@ -216,6 +216,7 @@
   TESTCASE_AUTO(Test13777_ParseLongNameNonCurrencyMode);
   TESTCASE_AUTO(Test13804_EmptyStringsWhenParsing);
   TESTCASE_AUTO(Test13840_ParseLongStringCrash);
+  TESTCASE_AUTO(Test13850_EmptyStringCurrency);
   TESTCASE_AUTO_END;
 }
 
@@ -9185,4 +9186,25 @@
     assertEquals("Should round-trip without crashing", expectedUString, actualUString);
 }
 
+void NumberFormatTest::Test13850_EmptyStringCurrency() {
+    IcuTestErrorCode status(*this, "Test13840_EmptyStringCurrency");
+
+    LocalPointer<NumberFormat> nf(NumberFormat::createCurrencyInstance("en-US", status), status);
+    if (status.errIfFailureAndReset()) { return; }
+    UnicodeString actual;
+    nf->format(1, actual, status);
+    assertEquals("Should format with US currency", u"$1.00", actual);
+    nf->setCurrency(u"", status);
+    nf->format(1, actual.remove(), status);
+    assertEquals("Should unset the currency on empty string", u"XXX\u00A01.00", actual);
+
+    // Try with nullptr
+    nf.adoptInstead(NumberFormat::createCurrencyInstance("en-US", status));
+    nf->format(1, actual.remove(), status);
+    assertEquals("Should format with US currency", u"$1.00", actual);
+    nf->setCurrency(nullptr, status);
+    nf->format(1, actual.remove(), status);
+    assertEquals("Should unset the currency on nullptr", u"XXX\u00A01.00", actual);
+}
+
 #endif /* #if !UCONFIG_NO_FORMATTING */

icu4c/source/test/intltest/numfmtst.h

diff --git a/icu4c/source/test/intltest/numfmtst.h b/icu4c/source/test/intltest/numfmtst.h
index b51e752..9f7a5c0 100644
--- a/icu4c/source/test/intltest/numfmtst.h
+++ b/icu4c/source/test/intltest/numfmtst.h
@@ -280,6 +280,7 @@
     void Test13777_ParseLongNameNonCurrencyMode();
     void Test13804_EmptyStringsWhenParsing();
     void Test13840_ParseLongStringCrash();
+    void Test13850_EmptyStringCurrency();
 
  private:
     UBool testFormattableAsUFormattable(const char *file, int line, Formattable &f);