Support ICU 62+

- ICU 62.1 icu4c DecimalFormat api now wraps the new NumberFormatter
  api.

- Update currency spacing accoring to ICU changes
  (http://bugs.icu-project.org/trac/ticket/6560)

- Disable tests that allowed different patterns for negative numbers,
  http://icu-project.org/apiref/icu4c/classDecimalFormat.html states
  that negative patterns serve only to specify the negative prefix
  and suffix. The number of digits, minimal digits and other
  characteristics are ignored in the negative subpattern.

  Support for different negative patterns may need to be added as a
  workaround.

Author: spevans

CoreFoundation/Locale.subproj/CFNumberFormatter.c

@@ -136,13 +136,16 @@ CFNumberFormatterRef CFNumberFormatterCreate(CFAllocatorRef allocator, CFLocaleR
     }
 
     if (kCFNumberFormatterNoStyle == style) {
+#if U_ICU_VERSION_MAJOR_NUM < 62
+        // ICU62+ is stricter about patterns matching attribute settings and setting UNUM_MAX_INTEGER_DIGITS = 42 would result in a pattern of  42x '#' not 1x '#' as is set here.
         UChar ubuff[1];
         status = U_ZERO_ERROR;
         ubuff[0] = '#';
 
         __cficu_unum_applyPattern(memory->_nf, false, ubuff, 1, NULL, &status);
 	__cficu_unum_setAttribute(memory->_nf, UNUM_MAX_INTEGER_DIGITS, 42);
 	__cficu_unum_setAttribute(memory->_nf, UNUM_MAX_FRACTION_DIGITS, 0);
+#endif
     }
     //Prior to Gala, CFLocaleCreateCopy() always just retained. This caused problems because CFLocaleGetValue(locale, kCFLocaleCalendarKey) would create a calendar, then set its locale to self, leading to a retain cycle
     //Since we're not in that situation here, and this is a frequently used path, we retain as we used to

TestFoundation/TestNumberFormatter.swift

@@ -10,6 +10,21 @@
 
 class TestNumberFormatter: XCTestCase {
 
+    var currencySpacing = ""
+#if !canImport(Darwin)
+    // This awfulness is needed until the non-Darwin versions are always using ICU >= 64 at which
+    // time the currenySpacing can be set to "\u{00A0}". This is just a way to allow the tests
+    // to run on Linux with both older and current ICU
+    override func setUp() {
+        super.setUp()
+
+        let numberFormatter = NumberFormatter()
+        numberFormatter.numberStyle = .currency
+        numberFormatter.currencyCode = "T"
+        currencySpacing = String((numberFormatter.string(from: 1)!.dropFirst().dropLast(4)))
+    }
+#endif
+
     func test_defaultPropertyValues() {
         let numberFormatter = NumberFormatter()
         XCTAssertEqual(numberFormatter.numberStyle, .none)
@@ -195,14 +210,14 @@ class TestNumberFormatter: XCTestCase {
         XCTAssertEqual(numberFormatter.maximumSignificantDigits, 6)
         XCTAssertEqual(numberFormatter.usesSignificantDigits, false)
         XCTAssertEqual(numberFormatter.formatWidth, 0)
-        XCTAssertEqual(numberFormatter.format, "¤¤#,##0.00;USD0.00;¤¤#,##0.00")
+        XCTAssertEqual(numberFormatter.format, "¤¤#,##0.00;USD\(currencySpacing)0.00;¤¤#,##0.00")
         XCTAssertEqual(numberFormatter.positiveFormat, "¤¤#,##0.00")
         XCTAssertEqual(numberFormatter.negativeFormat, "¤¤#,##0.00")
         XCTAssertNil(numberFormatter.multiplier)
         XCTAssertTrue(numberFormatter.usesGroupingSeparator)
         XCTAssertEqual(numberFormatter.groupingSize, 3)
         XCTAssertEqual(numberFormatter.secondaryGroupingSize, 0)
-        XCTAssertEqual(numberFormatter.string(from: NSNumber(1234567890)), "USD1,234,567,890.00")
+        XCTAssertEqual(numberFormatter.string(from: NSNumber(1234567890)), "USD\(currencySpacing)1,234,567,890.00")
     }
 
     func test_defaultCurrencyPluralPropertyValues() {
@@ -262,12 +277,12 @@ class TestNumberFormatter: XCTestCase {
         XCTAssertEqual(numberFormatter.string(from: -1.1), "-£1.10")
 
         numberFormatter.currencyCode = "T"
-        XCTAssertEqual(numberFormatter.format, "¤#,##0.00;T0.00;¤#,##0.00")
+        XCTAssertEqual(numberFormatter.format, "¤#,##0.00;T\(currencySpacing)0.00;¤#,##0.00")
         numberFormatter.currencyDecimalSeparator = "_"
-        XCTAssertEqual(numberFormatter.format, "¤#,##0.00;T0_00;¤#,##0.00")
+        XCTAssertEqual(numberFormatter.format, "¤#,##0.00;T\(currencySpacing)0_00;¤#,##0.00")
 
         let formattedString = numberFormatter.string(from: 42)
-        XCTAssertEqual(formattedString, "T42_00")
+        XCTAssertEqual(formattedString, "T\(currencySpacing)42_00")
     }
 
     func test_decimalSeparator() {
@@ -289,9 +304,9 @@ class TestNumberFormatter: XCTestCase {
         numberFormatter.numberStyle = .currency
         numberFormatter.currencyDecimalSeparator = "-"
         numberFormatter.currencyCode = "T"
-        XCTAssertEqual(numberFormatter.format, "¤#,##0.00;T0-00;¤#,##0.00")
+        XCTAssertEqual(numberFormatter.format, "¤#,##0.00;T\(currencySpacing)0-00;¤#,##0.00")
         let formattedString = numberFormatter.string(from: 42.42)
-        XCTAssertEqual(formattedString, "T42-42")
+        XCTAssertEqual(formattedString, "T\(currencySpacing)42-42")
     }
 
     func test_alwaysShowDecimalSeparator() {
@@ -623,18 +638,18 @@ class TestNumberFormatter: XCTestCase {
         XCTAssertEqual(formatter.minimumIntegerDigits, 0)
         formatter.locale = Locale(identifier: "en_US")
         XCTAssertEqual(formatter.string(from: 0), "USD.00")
-        XCTAssertEqual(formatter.string(from: 1.23), "USD1.23")
-        XCTAssertEqual(formatter.string(from: 123.4), "USD123.40")
+        XCTAssertEqual(formatter.string(from: 1.23), "USD\(currencySpacing)1.23")
+        XCTAssertEqual(formatter.string(from: 123.4), "USD\(currencySpacing)123.40")
 
         // If .minimumIntegerDigits is not set before .numberStyle change, update the value
         let formatter2 = NumberFormatter()
         XCTAssertEqual(formatter2.minimumIntegerDigits, 0)
         formatter2.numberStyle = .currencyISOCode
         XCTAssertEqual(formatter2.minimumIntegerDigits, 1)
         formatter2.locale = Locale(identifier: "en_US")
-        XCTAssertEqual(formatter2.string(from: 0.01), "USD0.01")
-        XCTAssertEqual(formatter2.string(from: 1.234), "USD1.23")
-        XCTAssertEqual(formatter2.string(from: 123456.7), "USD123,456.70")
+        XCTAssertEqual(formatter2.string(from: 0.01), "USD\(currencySpacing)0.01")
+        XCTAssertEqual(formatter2.string(from: 1.234), "USD\(currencySpacing)1.23")
+        XCTAssertEqual(formatter2.string(from: 123456.7), "USD\(currencySpacing)123,456.70")
     }
 
     func test_currencyAccountingMinimumIntegerDigits() {
@@ -663,6 +678,7 @@ class TestNumberFormatter: XCTestCase {
     func test_maximumIntegerDigits() {
         let numberFormatter = NumberFormatter()
         numberFormatter.maximumIntegerDigits = 3
+        numberFormatter.minimumIntegerDigits = 3
         let formattedString = numberFormatter.string(from: 1_000)
         XCTAssertEqual(formattedString, "000")
     }
@@ -790,7 +806,7 @@ class TestNumberFormatter: XCTestCase {
         numberFormatter.currencyCode = "T"
         numberFormatter.currencyDecimalSeparator = "/"
         let formattedString = numberFormatter.string(from: 42_000)
-        XCTAssertEqual(formattedString, "T42_000/00")
+        XCTAssertEqual(formattedString, "T\(currencySpacing)42_000/00")
 
     }
 
@@ -1127,8 +1143,8 @@ class TestNumberFormatter: XCTestCase {
         XCTAssertEqual(formatter.string(from: NSNumber(value: Double.pi)), "3.14159")
 
         formatter = NumberFormatter()
-        formatter.negativeFormat = "#.#########"
         formatter.positiveFormat = "#.#########"
+        formatter.negativeFormat = "-#.#########"
         XCTAssertEqual(formatter.string(from: NSNumber(value: 0.5)), "0.5")
         XCTAssertEqual(formatter.string(from: NSNumber(value: -0.5)), "-0.5")
     }
@@ -1206,7 +1222,7 @@ class TestNumberFormatter: XCTestCase {
             ("test_en_US_initialValues", test_en_US_initialValues),
             ("test_pt_BR_initialValues", test_pt_BR_initialValues),
             ("test_changingLocale", test_changingLocale),
-            ("test_settingFormat", test_settingFormat),
+            /* ⚠️ */ ("test_settingFormat", testExpectedToFail(test_settingFormat), "Mostly broken with ICU62+"),
             ("test_usingFormat", test_usingFormat),
             ("test_propertyChanges", test_propertyChanges),
         ]