Merchant route selection: very basic stuff works

Tests pass.

test/the_great_game/merchants/merchants_test.clj

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+(ns the-great-game.merchants.merchants-test
+  (:require [clojure.test :refer :all]
+            [the-great-game.utils :refer [deep-merge]]
+            [the-great-game.world.world :refer [default-world]]
+            [the-great-game.merchants.merchants :refer :all]))
+
+(deftest expected-price-test
+  (testing "Anticipated prices in markets"
+    (let [world (deep-merge
+                  default-world
+                  {:merchants
+                   {:archie
+                    {:known-prices
+                     {:buckie
+                      {:iron
+                       [{:price 1.7 :date 1}
+                        {:price 2 :date 0}]}}}}})]
+      (let [actual (expected-price (-> world :merchants :archie) :fish :edinburgh)
+            expected 1] ;;
+        (is (= actual expected) "if no information assume 1"))
+      (let [actual (expected-price (-> world :merchants :archie) :iron :buckie)
+            expected 1.7] ;;
+        (is (= actual expected) "if information select the most recent")))))

test/the_great_game/utils_test.clj

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+(ns the-great-game.utils-test
+  (:require [clojure.test :refer :all]
+            [the-great-game.utils :refer :all]))
+
+(deftest cyclic-tests
+  (testing "Detecting cyclic routes"
+    (let [actual (cyclic? '(:glasgow :edinburgh :glasgow))
+          expected true]
+      (is (= actual expected)))
+    (let [actual (cyclic? '(:edinburgh :dundee :aberdeen :buckie))
+          expected false]
+      (is (= actual expected)))))

test/the_great_game/world/routes_test.clj

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+(ns the-great-game.world.routes-test
+  (:require [clojure.test :refer :all]
+            [the-great-game.world.routes :refer :all]
+            [the-great-game.world.world :refer [default-world]]))
+
+
+(deftest routing-test
+  (testing "Routing: possible route"
+    (let [origin :buckie
+          destination :glasgow
+          routes (find-routes (:routes default-world) origin destination)]
+      (is
+        (= (first (first routes)) origin)
+        "Routes should be from the specified origin")
+      (is
+        (= (last (first routes)) destination)
+        "Routes should be from the specified destination")
+      (is
+        (= (count (set (map first routes))) 1)
+        "All routes should have the same origin")
+      (is
+        (= (count (set (map last routes))) 1)
+        "All routes should have the same destination")
+      (is
+        (= (count (set (map count routes))) 1)
+        "All selected routes should have the same length")
+      ))
+  (testing "Impossible route"
+    (let [origin :buckie
+          destination :london ;; not present in the routing map
+          actual (find-routes (:routes default-world) origin destination)]
+      (is (nil? actual) "There should be no route returned."))))
+

test/the_great_game/world/world_test.clj

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+(ns the-great-game.world.world-test
+  (:require [clojure.test :refer :all]
+            [the-great-game.world.world :refer :all]))
+