Fix edge case on swarm size calculation.

Fixes #12

RELEASES.md

@@ -1,3 +1,11 @@
+= 19.0.1
+
+- fixed bug in swarm size calculation (thanks to wollw!)
+
+= 19.0.0
+
+First version for game "Piranhas"
+
 = 1.2.1
 
 - fixed a bug which could lead to an infinite loop in the possible_move method

lib/software_challenge_client/game_rule_logic.rb

@@ -196,8 +196,9 @@ def self.neighbours(board, field)
   # @param current_biggest_swarm [Set<Field>] Aktuell größte zusammenhängende Feldmenge. Für rekursiven Aufruf.
   # @return [Set<Field>]
   def self.greatest_swarm_from_fields(board, fields_to_check, current_biggest_swarm = Set.new)
-    # stop searching when the size of the current found biggest set is bigger than the rest of the fields
-    return current_biggest_swarm if current_biggest_swarm.size > fields_to_check.size
+    # stop searching when the size of the current found biggest set is bigger
+    # than the rest of the fields or if there are no more fields to check
+    return current_biggest_swarm if current_biggest_swarm.size > fields_to_check.size || fields_to_check.empty?
 
     # start a new set of adjacent fields with the first field in fields_to_check
     current_swarm = Set.new

lib/software_challenge_client/version.rb

@@ -1,4 +1,4 @@
 # encoding: UTF-8
 module SoftwareChallengeClient
-  VERSION = "19.0.0"
+  VERSION = "19.0.1"
 end

spec/game_rule_logic_spec.rb

@@ -91,4 +91,24 @@
     expect(subject.swarm_size(gamestate.board, PlayerColor::BLUE)).to eq(10)
   end
 
+  it 'calculates correct swarm size with very few fishes' do
+    # this is an edge case to capture Issue #12
+    field =
+      <<~FIELD
+          ~ R ~ ~ ~ ~ ~ ~ ~ ~
+          ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
+          ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
+          ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
+          ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
+          ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
+          ~ ~ ~ ~ ~ O ~ ~ ~ ~
+          ~ ~ ~ ~ ~ O ~ ~ ~ ~
+          ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
+          ~ ~ ~ ~ ~ ~ ~ ~ ~ ~
+        FIELD
+    state_from_string!(field, gamestate)
+    expect(subject.swarm_size(gamestate.board, PlayerColor::RED)).to eq(1)
+    expect(subject.swarm_size(gamestate.board, PlayerColor::BLUE)).to eq(0)
+  end
+
 end