Rename Time#add_span to Time#shift

spec/std/time/time_spec.cr

@@ -113,7 +113,7 @@ describe Time do
     (time == time.clone).should be_true
   end
 
-  describe "#add_span" do
+  describe "#shift" do
     it "adds hours, minutes, seconds" do
       t1 = Time.utc(2002, 2, 25, 15, 25, 13)
       t2 = t1 + Time::Span.new 3, 54, 1
@@ -142,10 +142,10 @@ describe Time do
         location = Time::Location.fixed(offset)
 
         time = Time.new(1, 1, 1, location: location)
-        time.add_span(0, 1).should eq Time.new(1, 1, 1, nanosecond: 1, location: location)
-        time.add_span(0, 0).should eq time
+        time.shift(0, 1).should eq Time.new(1, 1, 1, nanosecond: 1, location: location)
+        time.shift(0, 0).should eq time
         expect_raises(ArgumentError) do
-          time.add_span(0, -1)
+          time.shift(0, -1)
         end
       end
     end
@@ -155,17 +155,17 @@ describe Time do
         location = Time::Location.fixed(offset)
 
         time = Time.new(9999, 12, 31, 23, 59, 59, nanosecond: 999_999_999, location: location)
-        time.add_span(0, -1).should eq Time.new(9999, 12, 31, 23, 59, 59, nanosecond: 999_999_998, location: location)
-        time.add_span(0, 0).should eq time
+        time.shift(0, -1).should eq Time.new(9999, 12, 31, 23, 59, 59, nanosecond: 999_999_998, location: location)
+        time.shift(0, 0).should eq time
         expect_raises(ArgumentError) do
-          time.add_span(0, 1)
+          time.shift(0, 1)
         end
       end
     end
 
     it "adds zero span" do
       time = Time.now
-      time.add_span(0, 0).should eq time
+      time.shift(0, 0).should eq time
     end
 
     describe "adds days" do

src/time.cr

@@ -509,16 +509,16 @@ struct Time
 
   # Returns a copy of this `Time` with *span* added.
   #
-  # See `#add_span` for details.
+  # See `#shift` for details.
   def +(span : Time::Span) : Time
-    add_span span.to_i, span.nanoseconds
+    shift span.to_i, span.nanoseconds
   end
 
   # Returns a copy of this `Time` with *span* subtracted.
   #
-  # See `#add_span` for details.
+  # See `#shift` for details.
   def -(span : Time::Span) : Time
-    add_span -span.to_i, -span.nanoseconds
+    shift -span.to_i, -span.nanoseconds
   end
 
   # Returns a copy of this `Time` with *span* added.
@@ -594,7 +594,7 @@ struct Time
   # There is no explicit limit on the input values but the addition must result
   # in a valid time between `0001-01-01 00:00:00.0` and
   # `9999-12-31 23:59:59.999_999_999`. Otherwise `ArgumentError` is raised.
-  def add_span(seconds : Int, nanoseconds : Int) : Time
+  def shift(seconds : Int, nanoseconds : Int) : Time
     if seconds == 0 && nanoseconds == 0
       return self
     end

src/time/format/parser.cr

@@ -46,7 +46,7 @@ struct Time::Format
       end
 
       time = Time.new @year, @month, @day, @hour, @minute, @second, nanosecond: @nanosecond, location: location
-      time = time.add_span 0, @nanosecond_offset
+      time = time.shift 0, @nanosecond_offset
 
       time
     end