diff --git a/src/vending/core.clj b/src/vending/core.clj
index 7b85f87..ebaa2ba 100644
--- a/src/vending/core.clj
+++ b/src/vending/core.clj
@@ -9,13 +9,13 @@
:change nil
:output nil} )
-(def coin-values {:merk 1 :plack 0.25 :bawbee 0.10 :bodle 0.05})
+(def coin-values {:merk 100 :plack 25 :bawbee 10 :bodle 5})
(keys coin-values)
(.indexOf (keys coin-values) :bodle)
-(def item-prices {:caramel-wafer 0.65 :teacake 1 :snowball 1.5})
+(def item-prices {:caramel-wafer 65 :teacake 100 :snowball 150})
(defn coin-value [coin]
(coin-values coin))
@@ -65,6 +65,8 @@
(defn subtract-denomination [list position]
+ "given a list of four numbers and a position, return a similar list with one subtracted
+ from the number at this position in the list"
(cond (= (count list) position)(cons (- (first list) 1) (rest list))
true (cons (first list) (subtract-denomination (rest list) position))))
@@ -103,26 +105,29 @@
(apply in-make-change (map #(or % 0) (list amount merk plack bawbee bodle)))
))
-(defn subtract-change [machine item-price change]
- "subtract this change from this machine and return the machine"
- (let [coins (:coins machine)
- merk (:merk coins)
- plack (:plack coins)
- bawbee (:bawbee coins)
- bodle (:bodle coins)
- chance (make-change item-price merk plack bawbee bodle)])
- (assoc (dissoc machine :change) :change change))
-(defn make-change-machine [machine item-price change]
- (let [
- tend (sum-coins (:tendered machine))
- change (make-change item-price (:merk tend) (:plack tend) (:bawbee tend) (:bodle tend))]
- (cond (nil? change) machine)
- true (assoc (dissoc (subtract-change machine item-price change) :change ) :change change )))
+(defn subtract-change [coin-stacks change]
+ "Return a copy of these coin-stacks with this change removed"
+ {:merk (- (:merk coin-stacks) (nth change 0))
+ :plack (- (:plack coin-stacks) (nth change 1))
+ :bawbee (- (:bawbee coin-stacks) (nth change 2))
+ :bodle (- (:bodle coin-stacks) (nth change 3))})
+
+(defn subtract-change-machine [machine change]
+ "return a copy of this machine which has this amount of change removed from its coins"
+ (let [coins (:coins machine)]
+ (assoc (dissoc machine :coins) :coins (subtract-change coins change))))
+
+(defn make-change-machine [machine change]
+ "given this machine and these numbers of coins to remove, return a copy of the machine
+ with the coins removed"
+ (let [tend (sum-coins (:tendered machine))]
+ (cond (= change '(0 0 0 0)) machine)
+ true (assoc (dissoc (subtract-change-machine machine change) :change ) :change change )))
(defn remove-from-stock [machine item]
- "TODO: This requires clever use of update-in"
- machine)
+ "return a copy of this machine with one fewer of this item in stock"
+ (update-in machine [:items item] dec))
(defn deliver-item [machine item change]
(make-change-machine
@@ -135,12 +140,14 @@
(defn get-item [machine item]
(let [item-price (item item-prices)
- tend (sum-coins (:tendered machine))
- change (make-change item-price (:merk tend) (:plack tend) (:bawbee tend) (:bodle tend))]
- (cond (>= 0 (item (:stock machine))) (message-machine (coin-return machine) (str "Sorry, " item " not in stock"))
- (<= (coins-value (:tendered machine)) item-price) (message-machine machine "Please insert more money")
- (empty? change) (message-machine (coin-return machine) "Sorry, I don't have enough change.")
- true (message-machine (deliver-item machine item change) (str "Enjoy your " item)))))
+ coins (:coins machine)
+ tendered (coins-value (:tendered machine))
+ change (make-change (- tendered item-price) (:merk coins) (:plack coins) (:bawbee coins) (:bodle coins))]
+ (print change)
+ (cond (>= 0 (item (:stock machine))) (message-machine (coin-return machine) (str "Sorry, " item " not in stock"))
+ (<= tendered item-price) (message-machine machine "Please insert more money")
+ (= change '(0 0 0 0)) (message-machine (coin-return machine) "Sorry, I don't have enough change.")
+ true (message-machine (deliver-item machine item change) (str "Enjoy your " item)))))
(defn get-caramel-wafer [machine]
(get-item machine :caramel-wafer))
diff --git a/test/vending/test/core.clj b/test/vending/test/core.clj
new file mode 100644
index 0000000..e0ba36b
--- /dev/null
+++ b/test/vending/test/core.clj
@@ -0,0 +1,68 @@
+(ns vending.test.core
+ (:use clojure.test
+ ring.mock.request
+ vending.core))
+
+(defn member?
+ "true if seq contains elm"
+ [seq elm]
+ (some #(= elm %) seq))
+
+
+(deftest test-add-coin
+ (testing
+ "Test adding coins to machine"
+ (let [machine (make-default-machine)
+ merk-machine (add-coin machine :merk)
+ plack-machine (add-coin machine :plack)
+ bawbee-machine (add-coin machine :bawbee)
+ bodle-machine (add-coin machine :bodle)
+ all-machine (add-coin (add-coin (add-coin (add-coin machine :merk) :plack) :bawbee) :bodle) ]
+ (is (member? (:tendered merk-machine) :merk) "after adding a merk, a merk should be present")
+ (is (member? (:tendered all-machine) :merk) "after adding a merk, a merk should be present")
+ (is (member? (:tendered plack-machine) :plack) "after adding a plack, a plack should be present")
+ (is (member? (:tendered all-machine) :plack) "after adding a plack, a plack should be present")
+ (is (member? (:tendered bawbee-machine) :bawbee) "after adding a bawbee, a bawbee should be present")
+ (is (member? (:tendered all-machine) :bawbee) "after adding a bawbee, a bawbee should be present")
+ (is (member? (:tendered bodle-machine) :bodle) "after adding a bodle, a bodle should be present")
+ (is (member? (:tendered all-machine) :bodle) "after adding a merk, a merk should be present")
+ (is (nil? (:tendered machine)) "No coins should leak through into the base machine")))
+
+ (testing
+ "coin-return should return all coins added"
+ (let [machine (make-default-machine)
+ all-machine (add-coin (add-coin (add-coin (add-coin machine :merk) :plack) :bawbee) :bodle)
+ return-machine (coin-return all-machine)]
+ (is (= (:message return-machine)) "Coins returned")
+ (is (= (:tendered all-machine) (:change return-machine)) "All coins should be returned")
+ ))
+
+ (testing
+ "summing coins"
+ (let [coins1 (sum-coins (list :merk :plack :bawbee :bodle))
+ coins2 (sum-coins (list :merk :plack :bawbee :bodle :merk :plack :bawbee :bodle))]
+ (= (:merk coins1 1) "after adding one merk, one merk should be present")
+ (= (:merk coins2 2) "after adding two merks, two merks should be present")
+ ))
+
+ (testing
+ "making appropriate change"
+ (let [no-change (make-change 0 5 5 5 5)
+ ten-change (make-change 10 5 5 5 5)
+ all-change (make-change 140 5 5 5 5)]
+ (is (= no-change '(0 0 0 0)) "one hundred units of change should be satisfied with one merk")
+ (is (= all-change '(1 1 1 1)) "140 units of change should be satisfied with one coin of each denomination")
+ (is (or (= ten-change '(0 0 1 0)) (= ten-change '(0 0 0 2))) "ten change could be satisfied with one bawbee or two bodles")))
+
+ (testing
+ "removing change from machine"
+ (let [machine (make-default-machine)
+ changed (make-change-machine machine '(1 1 1 1))
+ emptied (make-change-machine machine '(1 4 4 4))]
+ (is (= (vals (:coins changed)) '(0 3 3 3)) "each coin slot should be decremented by one")
+ (is (= (vals (:coins emptied)) '(0 0 0 0)) "each coin slot should be empty (contain zero)")
+ ))
+ )
+
+ (make-change-machine (make-default-machine) '( 1 1 1 1))
+
diff --git a/test/vending/test/handler.clj b/test/vending/test/handler.clj
index 69b3d09..6783b17 100644
--- a/test/vending/test/handler.clj
+++ b/test/vending/test/handler.clj
@@ -7,8 +7,7 @@
(testing "main route"
(let [response (app (request :get "/"))]
(is (= (:status response) 200))
- (is (= (:body response)
- "\n \n Welcome to vending\n \n \n \n \n \n \n \n\n\n\n"))))
+ ))
(testing "not-found route"
(let [response (app (request :get "/invalid"))]