Speed up DateTime.iso8601 by fast pathing similar to cext in our ruby version.

enebo · enebo · commit a2bc9a3a0dee · 2018-07-19T15:45:44.000-05:00
This is not identical.  The section after the cext looks different from our
code but seemingly all tests pass.  The other weird bit is undeprecating +
making Date._valid_civil?.

Nearly 2x speed up for ```DateTime.iso8601('1999-12-31T19:20:06')```.
diff --git a/core/src/main/java/org/jruby/ext/date/RubyDate.java b/core/src/main/java/org/jruby/ext/date/RubyDate.java
@@ -727,8 +727,7 @@ public static RubyDate today(ThreadContext context, IRubyObject self, IRubyObjec
         return new RubyDate(context.runtime, (RubyClass) self, new DateTime(getChronology(context, start, 0)).withTimeAtStartOfDay(), 0, start);
     }
 
-    @Deprecated // NOTE: should go away once no date.rb is using it
-    @JRubyMethod(name = "_valid_civil?", meta = true, required = 3, optional = 1, visibility = Visibility.PRIVATE)
+    @JRubyMethod(name = "_valid_civil?", meta = true, required = 3, optional = 1)
     public static IRubyObject _valid_civil_p(ThreadContext context, IRubyObject self, IRubyObject[] args) {
         final long sg = args.length > 3 ? val2sg(context, args[3]) : GREGORIAN;
         final Long jd = validCivilImpl(args[0], args[1], args[2], sg);
diff --git a/lib/ruby/stdlib/date.rb b/lib/ruby/stdlib/date.rb
@@ -684,10 +684,21 @@ def self.commercial(y=-4712, w=1, d=1, h=0, min=0, s=0, of=0, sg=ITALY)
   def self.new_by_frags(elem, sg) # :nodoc:
     raise ArgumentError, 'invalid date' unless elem
     
-    elem = rewrite_frags(elem)
-    elem = complete_frags(elem)
-    unless (jd = valid_date_frags?(elem, sg)) &&
-           (fr = valid_time_frags?(elem))
+
+    # More work to do if not :civil
+    if !elem.key?(:jd) && !elem.key?(:yday) &&
+        (year = elem[:year]) && (mon = elem[:mon]) && (mday = elem[:mday])
+      jd = Date._valid_civil?(year, mon, mday, sg)
+      elem[:hour] ||= 0
+      elem[:min] ||= 0
+      elem[:sec] ||= 0
+      elem[:sec] = 59 if elem[:sec] == 60
+    else
+      elem = rewrite_frags(elem)
+      elem = complete_frags(elem)
+      jd = valid_date_frags?(elem, sg)
+    end
+    unless jd && (fr = valid_time_frags?(elem))
       raise ArgumentError, 'invalid date'
     end
     fr += (elem[:sec_fraction] || 0) / 86400

Original file line number	Diff line number	Diff line change
`@@ -727,8 +727,7 @@ public static RubyDate today(ThreadContext context, IRubyObject self, IRubyObjec`
`727`	`727`	`return new RubyDate(context.runtime, (RubyClass) self, new DateTime(getChronology(context, start, 0)).withTimeAtStartOfDay(), 0, start);`
`728`	`728`	`}`
`729`	`729`
`730`		`- @Deprecated // NOTE: should go away once no date.rb is using it`
`731`		`- @JRubyMethod(name = "_valid_civil?", meta = true, required = 3, optional = 1, visibility = Visibility.PRIVATE)`
	`730`	`+ @JRubyMethod(name = "_valid_civil?", meta = true, required = 3, optional = 1)`
`732`	`731`	`public static IRubyObject _valid_civil_p(ThreadContext context, IRubyObject self, IRubyObject[] args) {`
`733`	`732`	`final long sg = args.length > 3 ? val2sg(context, args[3]) : GREGORIAN;`
`734`	`733`	`final Long jd = validCivilImpl(args[0], args[1], args[2], sg);`