Implement -components:fromDate:toDate:options:

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@39202 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,3 +1,12 @@
+2015-11-30: Niels Grewe <niels.grewe@halbordnung.de>
+
+	* Source/NSCalendar.h
+	* Headers/Foundation/NSCalendar.h:
+	Implement -components:fromDate:toDate:options:. (Not handling
+	NSWrapCalendarComponents yet.)
+	* Tests/base/NSCalendar/component-diff.m:
+	Test case for new functionality.
+
 2015-11-22 Riccardo Mottola <rm@gnu.org>
 
 	* Source/NSFileManager.m (createDirectoryAtPath)

Headers/Foundation/NSCalendar.h

@@ -194,6 +194,17 @@ enum
 
 - (NSDateComponents *) components: (NSUInteger) unitFlags
                          fromDate: (NSDate *) date;
+/**
+ * Compute the different between the specified components in the two dates.
+ * Values are summed up as long as now higher-granularity unit is specified.
+ * That means if you want to extract the year and the day from two dates
+ * which are 13 months + 1 day apart, you will get 1 as the result for the year
+ * but the rest of the difference in days. (29 <= x <= 32, depending on the 
+ * month). 
+ *
+ * Please note that the NSWrapCalendarComponents option that should affect the
+ * calculations is not presently supported.
+ */
 - (NSDateComponents *) components: (NSUInteger) unitFlags
                          fromDate: (NSDate *) startingDate
                            toDate: (NSDate *) resultDate

Source/NSCalendar.m

@@ -367,12 +367,81 @@ static NSRecursiveLock *classLock = nil;
 #endif
 }
 
+/*
+ * Convenience macro for field extraction.
+ * TODO: We need to implement NSWrapCalendarComponents, but it is unclear how that
+ * actually works.
+ */
+#define COMPONENT_DIFF(cal, units, components, toDate, nsunit, setSel, uunit, err) \
+do { if (units & nsunit) \
+  { \
+  int32_t uunit ## Diff = ucal_getFieldDifference(cal, toDate, uunit, &err); \
+  if (U_FAILURE(err)) \
+    { \
+      RELEASE(components); \
+      return nil; \
+    } \
+  [components setSel uunit ## Diff]; \
+  } \
+} while (0)
+
+
 - (NSDateComponents *) components: (NSUInteger) unitFlags
                          fromDate: (NSDate *) startingDate
                            toDate: (NSDate *) resultDate
                           options: (NSUInteger) opts
 {
+#if GS_USE_ICU == 1
+  NSDateComponents *comps = nil;
+  UErrorCode err = U_ZERO_ERROR;
+  UDate udateFrom = (UDate)floor([startingDate timeIntervalSince1970] * 1000.0);
+  UDate udateTo = (UDate)floor([resultDate timeIntervalSince1970] * 1000.0);
+  ucal_setMillis (my->cal, udateFrom, &err);
+  if (U_FAILURE(err))
+    {
+      return nil;
+    }
+  comps = [[NSDateComponents alloc] init];
+  /*
+   * Since the ICU field difference function automatically advances the calendar as appropriate, we
+   * need to process the units from the largest to the smallest.
+   */
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSEraCalendarUnit, setEra:, UCAL_ERA, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSYearCalendarUnit, setYear:, UCAL_YEAR, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSMonthCalendarUnit, setMonth:, UCAL_MONTH, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSWeekOfYearCalendarUnit, setWeek:, UCAL_WEEK_OF_YEAR, err);
+  if (!(unitFlags & NSWeekOfYearCalendarUnit))
+    {
+      /* We must avoid setting the same unit twice (it would be zero because
+       * of the automatic advancement.
+       */
+      COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSWeekCalendarUnit, setWeek:, UCAL_WEEK_OF_YEAR, err);
+    }
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSWeekOfMonthCalendarUnit, setWeekOfMonth:, UCAL_WEEK_OF_MONTH, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSDayCalendarUnit, setDay:, UCAL_DAY_OF_MONTH, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSWeekdayOrdinalCalendarUnit, setWeekdayOrdinal:, UCAL_DAY_OF_WEEK_IN_MONTH, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSWeekdayCalendarUnit, setWeekday:, UCAL_DAY_OF_WEEK, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSHourCalendarUnit, setHour:, UCAL_HOUR_OF_DAY, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSMinuteCalendarUnit, setMinute:, UCAL_MINUTE, err);
+  COMPONENT_DIFF(my->cal, unitFlags, comps, udateTo, NSSecondCalendarUnit, setSecond:, UCAL_SECOND, err);
+# if 0
+  if (unitFlags & NSCalendarUnitNanosecond)
+    {
+      int32_t ns = ucal_getFieldDifference(my->cal, udateTo, UCAL_MILLISECOND, &err) * 1000000;
+      if (U_FAILURE(err))
+        {
+          RELEASE(comps);
+          return nil;
+        }
+      [comps setNanosecond: ns];
+    }
+# endif
+  return AUTORELEASE(comps);
+
+
+#else
   return nil;
+#endif
 }
 
 - (NSDate *) dateByAddingComponents: (NSDateComponents *) comps

Tests/base/NSCalendar/component-diff.m

@@ -0,0 +1,55 @@
+#import "Testing.h"
+#import "ObjectTesting.h"
+#import <Foundation/NSCalendar.h>
+#import <Foundation/NSTimeZone.h>
+#import <Foundation/NSLocale.h>
+#include <stdio.h>
+
+#if	defined(GS_USE_ICU)
+#define	NSCALENDAR_SUPPORTED	GS_USE_ICU
+#else
+#define	NSCALENDAR_SUPPORTED	1 /* Assume Apple support */
+#endif
+
+int main()
+{
+  NSDateComponents *comps;
+  NSCalendar *cal;
+  NSDate *date;
+  NSDate *date2;
+  
+  START_SET("NSCalendar date component differences")
+  if (!NSCALENDAR_SUPPORTED)
+    SKIP("NSCalendar not supported\nThe ICU library was not available when GNUstep-base was built")
+  
+  cal = [[NSCalendar alloc] initWithCalendarIdentifier: NSGregorianCalendar];
+  [cal setFirstWeekday: 1];
+  
+  date = [NSDate dateWithString: @"2015-01-01 01:01:01 +0100"];
+  date2 = [NSDate dateWithString: @"2015-02-03 04:05:06 +0100"];
+
+  comps = [cal components: NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit
+                         | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit
+                 fromDate: date
+                   toDate: date2
+                  options: 0];
+  PASS([comps year] == 0, "year difference correct");
+  PASS([comps month] == 1, "month difference correct");
+  PASS([comps day] == 2, "day difference correct");
+  PASS([comps hour] == 3, "hour difference correct");
+  PASS([comps minute] == 4, "minute difference correct");
+  PASS([comps second] == 5, "second difference correct");
+  
+  comps = [cal components: NSDayCalendarUnit
+                 fromDate: date
+                   toDate: date2
+                  options: 0];
+  PASS([comps month] == NSNotFound, "no month returned if not requested");
+  PASS([comps day] == 33, "day difference without larger unit correct");
+  
+  
+  RELEASE(cal);
+  
+  END_SET("NSCalendar date component differences")
+  return 0;
+}