Merge pull request #18 from SOFware/feature/extend-cycle

Feature/extend cycle

lib/sof/cycle.rb

@@ -165,6 +165,8 @@ def ==(other) = to_h == other.to_h
     # Return the most recent completion date from the supplied array of dates
     def last_completed(dates) = dates.compact.map(&:to_date).max
 
+    def extend_period(_ = nil) = self
+
     # From the supplied anchor date, are there enough in-window completions to
     # satisfy the cycle?
     #

lib/sof/cycles/within.rb

@@ -12,6 +12,14 @@ def self.recurring? = false
 
       def to_s = "#{volume}x within #{date_range}"
 
+      def extend_period(count)
+        Cycle.for(
+          Parser.load(
+            parser.to_h.merge(period_count: period_count + count)
+          ).to_s
+        )
+      end
+
       def date_range
         return humanized_span unless active?
 

spec/sof/cycles/calendar_spec.rb

@@ -32,6 +32,7 @@ module SOF
     it_behaves_like "it computes #final_date(given)",
       given: "1971-01-01", returns: "1971-12-31".to_date
     it_behaves_like "last_completed is", :recent_date
+    it_behaves_like "it cannot be extended"
 
     describe "#recurring?" do
       it "repeats" do

spec/sof/cycles/end_of_spec.rb

@@ -39,6 +39,7 @@ module SOF
     it_behaves_like "#as_json returns the notation"
     it_behaves_like "it computes #final_date(given)",
       given: nil, returns: ("2020-01-01".to_date + 17.months).end_of_month
+    it_behaves_like "it cannot be extended"
 
     describe "#last_completed" do
       context "with an activated cycle" do

spec/sof/cycles/lookback_spec.rb

@@ -32,6 +32,7 @@ module SOF
     it_behaves_like "it computes #final_date(given)",
       given: "2003-03-08", returns: ("2003-03-08".to_date + 180.days)
     it_behaves_like "last_completed is", :recent_date
+    it_behaves_like "it cannot be extended"
 
     describe "#recurring?" do
       it "repeats" do

spec/sof/cycles/shared_examples.rb

@@ -51,3 +51,9 @@
     expect(subject.last_completed(dates)).to eq(expected)
   end
 end
+
+shared_examples_for "it cannot be extended" do
+  it "returns itself" do
+    expect(subject.extend_period(999)).to eq(subject)
+  end
+end

spec/sof/cycles/volume_only_spec.rb

@@ -30,6 +30,7 @@ module SOF
     it_behaves_like "it computes #final_date(given)",
       given: "2003-03-08", returns: nil
     it_behaves_like "last_completed is", :recent_date
+    it_behaves_like "it cannot be extended"
 
     describe "#recurring?" do
       it "does not repeat" do

spec/sof/cycles/within_spec.rb

@@ -34,6 +34,17 @@ module SOF
       given: "_", returns: ("2020-08-01".to_date + 180.days)
     it_behaves_like "last_completed is", :too_late
 
+    describe "#extend_period" do
+      it "increases the period by the given amount" do
+        aggregate_failures do
+          expect(cycle.notation).to eq("V2W180DF2020-08-01")
+
+          new_cycle = cycle.extend_period(30)
+          expect(new_cycle.notation).to eq("V2W210DF2020-08-01")
+        end
+      end
+    end
+
     describe "#recurring?" do
       it "does not repeat" do
         expect(cycle).not_to be_recurring