tests

21 files changed, 687 insertions, 259 deletions

diff --git a/doc/README.md b/doc/README.md
new file mode 100644
index 0000000..0452038
--- /dev/null
+++ b/doc/README.md
@@ -0,0 +1,51 @@
+# 9mm
+
+Introducing:
+Nine Mens Morris
+The Game
+
+A game about moving cows
+
+Featuring:
+Fennel
+The Language
+
+By:
+dozens
+the human
+
+## ABOUT
+
+Do you know what Nine Mens Morris looks like?
+It has three concentric rings, each containing eight spaces.
+Here's what it looks like:
+
+```
+1-----2-----3
+|     |     |
+| 4---5---6 |
+| |   |   | |
+| | 7-8-9 | |
+| | |   | | |
+0-1-2   3-4-5  +10
+| | |   | | |
+| | 6-7-8 | |
+| |   |   | |
+| 9---0---1 |  +20
+|     |     |
+2-----3-----4
+```
+
+## BACKGROUND
+
+9mm is legit a great game.
+
+One time i wrote an essay about the social contract implicit to nine mens morris:
+https://write.tildeverse.org/dozens/nine-mens-morris-cultural-meanings-and-social-contracts
+
+Kind of obsessed with this variation about COWS
+https://en.wikipedia.org/wiki/Morabaraba
+
+also look at these round cows
+https://en.wikipedia.org/wiki/Spherical_cow
+
diff --git a/justfile b/justfile
new file mode 100644
index 0000000..6fbee75
--- /dev/null
+++ b/justfile
@@ -0,0 +1,7 @@
+# list available recipes
+default:
+  just --list --unsorted
+
+# run tests
+test:
+  for f in lib/*.test.fnl; do fennel $f | faucet; done
diff --git a/lib/constants.fnl b/lib/constants.fnl
new file mode 100644
index 0000000..c88b279
--- /dev/null
+++ b/lib/constants.fnl
@@ -0,0 +1,91 @@
+(local neighbors
+  [
+    [1 2 10]
+    [2 1 3 5]
+    [3 2 15]
+    [4 5 11]
+    [5 2 4 6 8]
+    [6 5 14]
+    [7 8 12]
+    [8 5 7 9]
+    [9 8 13]
+    [10 1 11 22]
+    [11 4 10 12 19]
+    [12 7 11 16]
+    [13 9 14 18]
+    [14 6 13 15 21]
+    [15 3 14 24]
+    [16 12 17]
+    [17 16 18 20]
+    [18 13 17]
+    [19 11 20]
+    [20 17 19 21 23]
+    [21 14 20]
+    [22 10 23]
+    [23 20 22 24]
+    [24 15 23]
+    ])
+
+(local mills
+  [
+   [1 2 3]
+   [4 5 6]
+   [7 8 9]
+   [10 11 12]
+   [13 14 15]
+   [16 17 18]
+   [19 20 21]
+   [22 23 24]
+   [1 10 22]
+   [4 11 19]
+   [7 12 16]
+   [2 5 8]
+   [17 20 23]
+   [9 13 18]
+   [6 14 21]
+   [3 15 24]
+   ])
+
+; these are the only moves that are valid
+; i am somewhat bothered by all the wasted space
+; by 2-3A and 5-6A e.g.
+; Incidentally these are all in order of appearance
+; so when you find a match,
+; you can also update that index of `moves` to the current player number
+(local spaces [
+  "1A" "4A" "7A"
+  "2B" "4B" "6B"
+  "3C" "4C" "5C"
+  "1D" "2D" "3D"
+  "5D" "6D" "7D"
+  "3E" "4E" "5E"
+  "2F" "4F" "6F"
+  "1G" "4G" "7G"
+  ])
+
+; This is what the game board looks like
+; it's also used to display the state of the game
+; the Xs are converted to "%d" later for string templating
+; they are Xs here so that it looks pretty =)
+(local board [
+  "  1 2 3 4 5 6 7"
+  "A x-----x-----x" ;; 1 2 3
+  "  |     |     |" ;;
+  "B | x---x---x |" ;; 4 5 6
+  "  | |   |   | |" ;;
+  "C | | x-x-x | |" ;; 7 8 9
+  "  | | |   | | |" ;;
+  "D x-x-x   x-x-x" ;; 10 11 12 13 14 15
+  "  | | |   | | |" ;;
+  "E | | x-x-x | |" ;; 16 17 18
+  "  | |   |   | |" ;;
+  "F | x---x---x |" ;; 19 20 21
+  "  |     |     |" ;;
+  "G x-----x-----x" ;; 22 23 24
+  ])
+
+{: board
+ : mills
+ : neighbors
+ : spaces}
+
diff --git a/lib/contains.test.fnl b/lib/contains.test.fnl
index 1c7fb06..45a00af 100644
--- a/lib/contains.test.fnl
+++ b/lib/contains.test.fnl
@@ -1,11 +1,17 @@
-(let [{: contains } (require :lib.contains)]
-  (let [given "a list and an element it contains"
-        should "returns true"
-        expected true
-        actual (contains [:apple :orange :pear] :apple)]
-    (assert (= actual expected) (.. "Given " given " should " should)))
-  (let [given "a list and an element it does not contain"
-        should "returns false"
-        expected false
-        actual (contains [:apple :orange :pear] :gorilla)]
-    (assert (= actual expected) (.. "Given " given " should " should))))
+(let [{: contains } (require :lib.contains)
+      {: describe } (require :lib.test)
+      {: describe :end test-end} (require :lib.test)
+      ]
+
+       (describe "contains()" (fn [t]
+                                (t {:given "a list and an element it contains"
+                                    :should "returns true"
+                                    :expected true
+                                    :actual (contains [:apple :orange :pear] :apple)}
+                                   )
+                                (t {:given "a list and an element it does not contain"
+                                    :should "returns false"
+                                    :expected false
+                                    :actual (contains [:apple :orange :pear] :gorilla)
+                                    })
+                                (test-end))))
diff --git a/lib/either.test.fnl b/lib/either.test.fnl
index fc819dc..8ae0c08 100644
--- a/lib/either.test.fnl
+++ b/lib/either.test.fnl
@@ -1,40 +1,41 @@
-(local {: pprint} (require :lib.tableprint))
-
-(let [{
-       : Either
-       : Left
-       : Right
-       } (require :lib.either)]
-
-  ;; either
-  ;(print "Either Inspection")
-  ;(pprint Either)
-
-  ;; you can set and get values
-  (let [ v :poop x (Either:new v)]
-    (assert (= v x.value) (.. "The value is " v)))
-
-  (let [r (Right:new "rain")
-        map (r:map #(.. "b" $1))
-        expected :brain
-        actual (. map :value)
-        ]
-    (assert (= expected actual) "You can map a Right value"))
-
-  (let [l (Left:new "rain")
-        map (l:map #(.. "b" $1))
-        expected :rain
-        actual (. map :value)
-        ]
-    (assert (= expected actual) "You can NOT map a Left value"))
-
-  (let [e (Either.of "rank")
-        map (e:map #(.. "f" $1))
-        expected :frank
-        actual (. map :value)
-        ]
-    (assert (= expected actual) "You can map a Either.of"))
-
-
-
-)
+(let [{: pprint} (require :lib.tableprint)
+      {: describe :end test-end} (require :lib.test)
+      {: Either : Left : Right } (require :lib.either)]
+  (describe "Either" (fn [t]
+                       (t {:given "a new either"
+                           :should "set its value correctly"
+                           :expected :poop
+                           :actual (. (Either:new :poop) :value)
+                           })
+                       (t
+                        (let [r (Right:new "rain")
+                              map (r:map #(.. "b" $1))
+                              expected :brain
+                              actual (. map :value)]
+                          {:given "a Right of some value"
+                           :should "map"
+                           expected
+                           actual
+                           }))
+                       (t
+                        (let [ l (Left:new "rain")
+                              map (l:map #(.. "b" $1))
+                              expected :rain
+                              actual (. map :value)
+                              ]
+                          {:given "a Left of some value"
+                           :should "not map"
+                           expected
+                           actual
+                           }))
+                       (t
+                        (let [ e (Either.of "rank")
+                              map (e:map #(.. "f" $1))
+                              expected :frank
+                              actual (. map :value) ]
+                          {:given "Either.of"
+                           :should "map"
+                           expected
+                           actual
+                           }))
+                       (test-end))))
diff --git a/lib/equal.fnl b/lib/equal.fnl
new file mode 100644
index 0000000..cc34ada
--- /dev/null
+++ b/lib/equal.fnl
@@ -0,0 +1,22 @@
+;; thanks:
+;; https://gist.github.com/sapphyrus/fd9aeb871e3ce966cc4b0b969f62f539
+;; and antifennel
+(fn deep-equals [o1 o2 ignore-mt]
+  (when (= o1 o2) (lua "return true"))
+  (local o1-type (type o1))
+  (local o2-type (type o2))
+  (when (not= o1-type o2-type) (lua "return false"))
+  (when (not= o1-type :table) (lua "return false"))
+  (when (not ignore-mt)
+    (local mt1 (getmetatable o1))
+    (when (and mt1 mt1.__eq)
+      (let [___antifnl_rtn_1___ (= o1 o2)] (lua "return ___antifnl_rtn_1___"))))
+  (each [key1 value1 (pairs o1)]
+    (local value2 (. o2 key1))
+    (when (or (= value2 nil) (= (deep-equals value1 value2 ignore-mt) false))
+      (lua "return false")))
+  (each [key2 _ (pairs o2)]
+    (when (= (. o1 key2) nil) (lua "return false")))
+  true)	
+
+{:equal deep-equals}
diff --git a/lib/equal.test.fnl b/lib/equal.test.fnl
new file mode 100644
index 0000000..0ee8da7
--- /dev/null
+++ b/lib/equal.test.fnl
@@ -0,0 +1,28 @@
+(let [{: equal} (require :lib.equal)
+      {: describe :end test-end} (require :lib.test)]
+  (describe "equal()" (fn [t]
+                       (t {:given "two equal tables"
+                           :should "return true"
+                           :expected true
+                           :actual (equal [:orange :apple :pear] [:orange :apple :pear]) })
+                       (t {:given "two different tables"
+                           :should "return false"
+                           :expected false
+                           :actual (equal [:apple :pear] [:orange :apple :pear]) })
+                       (t {:given "equal strings"
+                           :should "be true"
+                           :expected true
+                           :actual (equal :apple :apple) })
+                       (t {:given "different strings"
+                           :should "be false"
+                           :expected false
+                           :actual (equal :apple :pear) })
+                       (t {:given "equal bools"
+                           :should "be true"
+                           :expected true
+                           :actual (equal true true) })
+                       (t {:given "different strings"
+                           :should "be false"
+                           :expected false
+                           :actual (equal true false) })
+                       (test-end))))
diff --git a/lib/flip.fnl b/lib/flip.fnl
new file mode 100644
index 0000000..9d21b63
--- /dev/null
+++ b/lib/flip.fnl
@@ -0,0 +1,6 @@
+(fn flip [t]
+  "takes a table of {key value} and returns a table of {value key}"
+  (collect [k v (pairs t)] (values v k)))
+
+{: flip}
+
diff --git a/lib/flip.test.fnl b/lib/flip.test.fnl
new file mode 100644
index 0000000..32fa005
--- /dev/null
+++ b/lib/flip.test.fnl
@@ -0,0 +1,13 @@
+(let [{: flip} (require :lib.flip)
+      {: describe :end test-end} (require :lib.test)]
+  (describe "flip()" (fn [t]
+                       (let [input {:apple "red" :banana "yellow"}
+                             expected {:red "apple" :yellow "banana"}
+                             ]
+                         (t {:given "a table"
+                             :should "flip that table!"
+                             : expected
+                             :actual (flip input)})
+                         (test-end)))))
+
+
diff --git a/lib/head.test.fnl b/lib/head.test.fnl
index 7514121..1209599 100644
--- a/lib/head.test.fnl
+++ b/lib/head.test.fnl
@@ -1,11 +1,12 @@
-(let [{: head } (require :lib.head)]
-  (let [given "a lift of elements"
-        it "returns the first element of a list"
-        expected :apple
-        actual (head [:apple :orange :pear])]
-    (assert (= actual expected) (.. "Given " given " it " it)))
-  (let [given "an empty list"
-        it "returns an empty list"
-        expected 0
-        actual (length (head []))]
-    (assert (= actual expected) (.. "Given " given " it " it))))
+(let [{: head} (require :lib.head)
+      {: describe :end test-end} (require :lib.test)]
+  (describe "head()" (fn [t]
+                       (t {:given "a list of elements"
+                           :should "returns the first element of a list"
+                           :expected :apple
+                           :actual  (head [:apple :orange :pear])})
+                       (t {:given "an empty list"
+                           :should "returns an empty list"
+                           :expected 0
+                           :actual (length (head []))})
+                       (test-end))))
diff --git a/lib/index.fnl b/lib/index.fnl
index 4d15b9a..7579a1d 100644
--- a/lib/index.fnl
+++ b/lib/index.fnl
@@ -1,13 +1,19 @@
-(local {:contains contains} (require :lib.contains))
-(local {:head head} (require :lib.head))
-(local {:mill? mill?} (require :lib.mill))
-(local {:pprint pprint} (require :lib.tableprint))
-(local {:tail tail} (require :lib.tail))
+(local {: contains} (require :lib.contains))
+(local {: flip} (require :lib.flip))
+(local {: head} (require :lib.head))
+(local {: keys} (require :lib.keys))
+(local {: mill?} (require :lib.mill))
+(local {: pprint} (require :lib.tableprint))
+(local {: slice} (require :lib.slice))
+(local {: tail} (require :lib.tail))
 
 {
- :contains contains
- :head head
- :mill? mill?
- :pprint pprint
- :tail tail
+ : contains
+ : flip
+ : head
+ : keys
+ : mill?
+ : pprint
+ : slice
+ : tail
  }
diff --git a/lib/keys.fnl b/lib/keys.fnl
new file mode 100644
index 0000000..0f3364a
--- /dev/null
+++ b/lib/keys.fnl
@@ -0,0 +1,7 @@
+(fn keys [t]
+  "takes a table returns a sequential list of its keys"
+  (local out [])
+  (each [k v (pairs t)] (table.insert out k))
+  out)
+
+{: keys}
diff --git a/lib/keys.test.fnl b/lib/keys.test.fnl
new file mode 100644
index 0000000..413a773
--- /dev/null
+++ b/lib/keys.test.fnl
@@ -0,0 +1,13 @@
+(let [{: keys} (require :lib.keys)
+      {: describe :end test-end} (require :lib.test)]
+  (describe "keys()" (fn [t]
+                       (let [input {:apple :red :banana :yellow}
+                             actual (keys input)
+                             sorted (table.sort actual) ;; SIDE EFFECT!!
+                             ]
+                         (t {:given "a table"
+                             :should "returns a list of keys"
+                             :expected [:apple :banana]
+                             : actual})
+                         (test-end)))))
+
diff --git a/lib/mill.fnl b/lib/mill.fnl
index de54128..e3b3337 100644
--- a/lib/mill.fnl
+++ b/lib/mill.fnl
@@ -1,16 +1,45 @@
 (local {: contains} (require :lib.contains))
 
-;; Does this move result in a mill?
-(fn mill? [rules state move]
-  (let [candidates (icollect [_ mill (ipairs rules)] (if (contains mill move) mill))
-        candidate->moves (icollect [_ spaces (ipairs candidates)]
-                                  (icollect [_ space (ipairs spaces)] (. state space)) )
-        candidate-mill? (icollect [_ moves (ipairs candidate->moves)]
-                                  (accumulate [acc true
-                                              idx m (ipairs moves)]
-                                              (and acc (not= 0 m) (= (. moves idx) m)))) ]
-    (accumulate [acc true
-                 _ x (ipairs candidate-mill?)]
-                (and acc x))))
-
-{: mill?}
+
+(fn get-candidates [all-mills next-move]
+  "a list of mills that contain next-move"
+  (icollect [_ mill (ipairs all-mills)] (if (contains mill next-move) mill)))
+
+(fn candidates->moves [candidates current-moves move player]
+  "a list of the candidate mills expressed as current moves"
+  (icollect [_ spaces (ipairs candidates)]
+    (icollect [_ space (ipairs spaces)] 
+              (if (= space move) :x (. current-moves space)))))
+
+(fn moves->mills [spaces player]
+  "a list of bools if the candidate moves + player are all the same"
+  (let [next-move (icollect [_ y (ipairs spaces)]
+                            (icollect [_ x (ipairs y)]
+                                      (if (= x :x) player x))) ]
+    (icollect [_ move (ipairs next-move)]
+      (accumulate [acc true
+                   idx m (ipairs move)]
+        (and acc (= player m))))))
+
+(fn any [t]
+	(accumulate [acc false
+               i x (ipairs t)]
+               (or acc x)))
+
+
+(fn mill? [all-mills current-moves next-move player]
+  "Does the current move for the current player create a mill?"
+  (let [candidates (get-candidates all-mills next-move)
+        moves (candidates->moves candidates current-moves next-move player)
+        mills (moves->mills moves player)
+        result (any mills)]
+		result))
+
+{: mill?
+ ;; not for consumption,
+ ;; just for testing:
+ : get-candidates
+ : candidates->moves
+ : moves->mills
+ : any
+ }
diff --git a/lib/mill.test.fnl b/lib/mill.test.fnl
index 358b218..8bd3522 100644
--- a/lib/mill.test.fnl
+++ b/lib/mill.test.fnl
@@ -1 +1,141 @@
-;; TODO: test me
+(let [{: describe
+       :end test-end} (require :lib.test)
+      {: mill?
+       : get-candidates
+       : candidates->moves
+       : moves->mills
+       : any
+       } (require :lib.mill)
+      {: mills } (require :lib.constants)
+      with-mills (partial mill? mills)]
+
+
+  (describe "Mill" (fn []
+    (describe "#get-candidates()" (fn [t]
+        (t
+         (let [move 3
+							 expected [[1 2 3] [3 15 24]]
+               moves [ 1 1 0 2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ]
+							]
+				 	{:given (string.format "a move of %d" move)
+					 :should "return [[1 2 3] [3 15 24]]" 
+           : expected 
+           :actual (get-candidates mills move)
+           }))
+        (t
+         (let [move 1
+							 expected [[1 2 3] [1 10 22]]
+               moves [ 0 0 0 ]
+							]
+				 	{:given (string.format "a move of %d" move)
+					 :should "return [[1 2 3] [1 10 22]]" 
+           : expected 
+           :actual (get-candidates mills move)
+           }))))
+				
+
+    (describe "#candidates->moves()" (fn [t]
+          (t 
+						(let [candidates [[1 2 3] [1 10 22]] 
+								  moves [0 1 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 2]
+								  expected [[:x 1 1] [:x 2 2]]
+								  move 1
+								  player 2
+								  ]
+							 {:given "a list of spaces and of current moves"
+								:should "return a map of spaces to moves"
+								: expected
+								:actual (candidates->moves candidates moves move player)
+								}))
+          (t 
+						(let [candidates [[1 2 3] [3 15 24]]
+								  moves [ 1 1 0 2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ]
+							 		expected [[1 1 :x] [:x 0 0]]
+									move 3
+									player 1
+									]
+							 {:given "a list of candidates and of current moves"
+								:should "return an x-map of spaces to moves"
+								: expected
+								:actual (candidates->moves candidates moves move player)
+								}))))
+
+
+    (describe "#moves->mills()" (fn [t]
+          (t 
+						(let [spaces [[:x 1 1] [:x 2 2]]
+									moves [0 1 1 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 2]
+									player 2
+									]
+							 {:given "a list of spaces and of current moves"
+								:should "return a map of spaces to moves"
+								:expected [false true]
+								:actual (moves->mills spaces player)
+								}))
+          (t 
+						(let [spaces [[1 1 :x] [:x 0 0]]
+								  moves [ 1 1 0 2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ]
+									player 1
+									]
+							 {:given "a list of canditate-moves and of current moves"
+								:should "return a map of spaces to moves"
+								:expected [true false]
+								:actual (moves->mills spaces player)
+								}))))
+
+
+    (describe "#any()" (fn [t]
+        (t {:given "a table of false false true"
+            :should "return true"
+            :expected true
+            :actual (any [false false true])
+           })
+        (t {:given "a table of true false"
+            :should "return true"
+            :expected true
+            :actual (any [true false])
+           })
+        (t {:given "a single false"
+            :should "return false"
+            :expected false
+            :actual (any [false])
+           })
+        (t {:given "a single true"
+            :should "return true"
+            :expected true
+            :actual (any [true])
+           })))
+
+
+    (describe "#mill?()" (fn [t]
+        (t 
+          (let [move 1
+                player 1
+								moves [0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0]
+                with-moves (partial with-mills moves)]
+            {:given (string.format "a move of P%d:%d with moves %s" player move (table.concat moves ","))
+             :should "not be a mill"
+             :expected false
+             :actual (with-moves move player)
+             }))
+        (t 
+          (let [move 3
+                player 1
+                moves [1 1 0]
+                with-moves (partial with-mills moves)]
+            {:given (string.format "a move of P%d:%d with moves %s" player move (table.concat moves ","))
+             :should "be a mill"
+             :expected true
+             :actual (with-moves move player)
+             }))
+        (t 
+          (let [move 3
+                player 1
+                moves [ 1 1 0 2 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ]
+                with-moves (partial with-mills moves)]
+            {:given (string.format "a move of P%d:%d with moves %s" player move (table.concat moves ","))
+             :should "be a mill"
+             :expected true
+             :actual (with-moves move player)
+             }))))
+    (test-end))))
diff --git a/lib/slice.fnl b/lib/slice.fnl
new file mode 100644
index 0000000..4f0de0f
--- /dev/null
+++ b/lib/slice.fnl
@@ -0,0 +1,5 @@
+(fn slice [t start stop]
+  (fcollect [i start (or stop (length t))]
+    (. t i)))
+
+{: slice}
diff --git a/lib/slice.test.fnl b/lib/slice.test.fnl
new file mode 100644
index 0000000..9293f93
--- /dev/null
+++ b/lib/slice.test.fnl
@@ -0,0 +1,19 @@
+(let [{: slice} (require :lib.slice)
+      {: describe :end test-end} (require :lib.test)]
+  (describe "slice()" (fn [t]
+                       (t 
+                         (let [t [:apple :orange :pear :banana :strawberry]
+                              ]
+                           {:given "a list of elements and a start"
+                            :should "return the list starting at start"
+                            :expected [:orange :pear :banana :strawberry]
+                            :actual  (slice t 2)}))
+                       (t 
+                         (let [t [:apple :orange :pear :banana :strawberry]
+                              ]
+                           {:given "a list of elements and a start and a stop"
+                            :should "return the items between the two"
+                            :expected [:orange :pear]
+                            :actual  (slice t 2 3)}))
+                       (test-end))))
+
diff --git a/lib/tail.test.fnl b/lib/tail.test.fnl
index 358b218..e507a0b 100644
--- a/lib/tail.test.fnl
+++ b/lib/tail.test.fnl
@@ -1 +1,19 @@
-;; TODO: test me
+(let [{: tail} (require :lib.tail)
+      {: describe :end test-end} (require :lib.test)]
+  (describe "tail()" (fn [t]
+                       (t {:given "a list"
+                           :should "return it minus the head"
+                           :expected [:apple :pear]
+                           :actual (tail [:orange :apple :pear])
+                           })
+                       (t {:given "a single item list"
+                           :should "return empty list"
+                           :expected []
+                           :actual (tail [:orange])
+                           })
+                       (t {:given "an empty list"
+                           :should "return empty list"
+                           :expected []
+                           :actual (tail [])
+                           })
+                       (test-end))))
diff --git a/lib/test.fnl b/lib/test.fnl
new file mode 100644
index 0000000..fbaaf8d
--- /dev/null
+++ b/lib/test.fnl
@@ -0,0 +1,52 @@
+(local {: pprint} (require :lib.tableprint))
+(local {: equal} (require :lib.equal))
+
+(var plan 0)
+
+(fn once [funky]
+  (var bang false)
+  (fn [...]
+    (if (not bang)
+      (do
+        (funky ...)
+        (set bang true)))))
+
+(fn test [obj]
+  (let [{: given : should : actual : expected} obj
+        ok (if (equal actual expected) :ok "not ok")
+        description (.. "Given " given " should " should)
+        ]
+    (set plan (+ 1 plan))
+    (print (.. ok " " plan " - " description))
+    (if (= "not ok" ok)
+      (do
+        (print "  ---")
+        (if (= :table (type expected))
+          (do
+            (print (.. "  expected: " ))
+            (pprint expected))
+          (print (.. "  expected: " (tostring expected))))
+        (if (= :table (type actual))
+          (do
+            (print (.. "  actual: " ))
+            (pprint actual))
+          (print (.. "  actual: " (tostring actual))))
+        (print "  ...")
+        )
+      )
+    ))
+
+(local print-header (once (fn [] (print "TAP version 14"))))
+
+(fn desc [str cb]
+  (print-header)
+  (print (.. "#" str))
+  (cb test)
+  )
+(fn end []
+  (print (.. 1 ".." plan))
+  )
+
+
+{:describe desc
+ : end}
diff --git a/lib/test.test.fnl b/lib/test.test.fnl
new file mode 100644
index 0000000..7958141
--- /dev/null
+++ b/lib/test.test.fnl
@@ -0,0 +1,19 @@
+(let [{: describe :end test-end} (require :lib.test)]
+  (fn add [x y] (let [x (or x 0)
+                      y (or y 0)]
+                  (+ x y)))
+  (describe "add()" (fn [test]
+                  (let [should "return the right number"]
+                    (test {:given "two numbers"
+                           : should
+                           :actual (add 2 3)
+                           :expected 5})
+                    (test {:given "no arguments"
+                           :should "return 0"
+                           :actual (add)
+                           :expected 0})
+                    (test {:given "zero"
+                           : should
+                           :actual (add 0 4)
+                           :expected 4}))
+                  (test-end))))
diff --git a/main.fnl b/main.fnl
index 169f4f9..d9ec3b4 100644
--- a/main.fnl
+++ b/main.fnl
@@ -1,41 +1,16 @@
-; Introducing:
-; Nine Mens Morris
-; The Game
-;
-; Featuring:
-; Fennel
-; The Language
-;
-; By:
-; dozens
-; the human
-;
-; Do you know what Nine Mens Morris looks like?
-; It has three concentric rings, each containing eight spaces.
-; Here's what it looks like:
-;
-; 1-----2-----3
-; |     |     |
-; | 4---5---6 |
-; | |   |   | |
-; | | 7-8-9 | |
-; | | |   | | |
-; 0-1-2   3-4-5  +10
-; | | |   | | |
-; | | 6-7-8 | |
-; | |   |   | |
-; | 9---0---1 |  +20
-; |     |     |
-; 2-----3-----4
-
-
 ;; helper and utility functions
 (local {
-  :contains contains
-  :head head
+  : contains
+  : head
+  : flip
+  : pprint
+  : slice
   :mill? mill-maker
-  :pprint pprint
   } (require :lib.index))
+;; constants...more like just strings
+(local const (require :lib.constants))
+;; front-loading mill with a partial
+(local mill? (partial mill-maker const.mills))
 
 
 ; there are three phases of play:
@@ -43,19 +18,19 @@
 ; (plus one for capturing)
 ; (plus one for complete)
 (local stages {
-  :placing  1
-  :moving   2
-  :flying   3
-  :capture  4
-  :complete 5
+  :placing  1 ;; placing the cows
+  :moving   2 ;; moving the cows
+  :flying   3 ;; flying the cows
+  :capture  4 ;; capture a cow (we do not shoot cows)
+  :complete 5 ;; no more cows!
 })
 
 
 ; there are two players
 ; their names are LUIGI and MARIO
 (local player {
-  :one 1 ;; luigi
-  :two 2 ;; mario
+  :one 1 ;; luigi has light cows
+  :two 2 ;; mario has DARK cows >:)
 })
 
 
@@ -68,67 +43,14 @@
 (local moves (fcollect [i 1 24] 0))
 
 
-(local rules {
-; what moves are legal from each space
-; slash what neighbors does each space have
-  :neighbors [
-    [1 2 10]
-    [2 1 3 5]
-    [3 2 15]
-    [4 5 11]
-    [5 2 4 6 8]
-    [6 5 14]
-    [7 8 12]
-    [8 5 7 9]
-    [9 8 13]
-    [10 1 11 22]
-    [11 4 10 12 19]
-    [12 7 11 16]
-    [13 9 14 18]
-    [14 6 13 15 21]
-    [15 3 14 24]
-    [16 12 17]
-    [17 16 18 20]
-    [18 13 17]
-    [19 11 20]
-    [20 17 19 21 23]
-    [21 14 20]
-    [22 10 23]
-    [23 20 22 24]
-    [24 15 23]
-  ]
-; sixteen combinations of spaces form a mill
-  :mills [
-    [1 2 3]
-    [4 5 6]
-    [7 8 9]
-    [10 11 12]
-    [13 14 15]
-    [16 17 18]
-    [19 20 21]
-    [22 23 24]
-    [1 10 22]
-    [4 11 19]
-    [7 12 16]
-    [2 5 8]
-    [17 20 23]
-    [9 13 18]
-    [6 14 21]
-    [3 15 24]
-  ]
-})
-
-(fn mill? [state move] (partial mill-maker rules.mills))
-
-
 ; game state object
 (local game {
   :player player.one
   :stage stages.placing
   :update (fn [self move]
-             (if (mill? moves move)
+             (if (mill? moves move self.player)
                (do
-                 (print "MILLLLLLLLLLLLL!")
+                 (print "Mooooooo")
                  (tset self :stage stages.capture)
                  )
                (tset self :player (if (= player.one self.player) player.two player.one))
@@ -137,93 +59,59 @@
 })
 
 
-
-
-
-; This is what the game board looks like
-; it's also used to display the state of the game
-; the Xs are converted to "%d" later for string templating
-; they are Xs here so that it looks pretty =)
-(local board [
-  "  1 2 3 4 5 6 7"
-  "A x-----x-----x"
-  "  |     |     |"
-  "B | x---x---x |"
-  "  | |   |   | |"
-  "C | | x-x-x | |"
-  "  | | |   | | |"
-  "D x-x-x   x-x-x"
-  "  | | |   | | |"
-  "E | | x-x-x | |"
-  "  | |   |   | |"
-  "F | x---x---x |"
-  "  |     |     |"
-  "G x-----x-----x"
-])
-
-
+(fn string-upper [s]
+  (.. (string.upper (string.sub s 1 1)) (string.sub s 2)))
 
 
 ; Print! That! Board!
 (fn print-board [board moves]
-  (var total-count -2) ; lol,  m-a-g-i-c
-                       ; just kidding, it's so that -2 + 3 = 1
-                       ; which is where i want to start indexing my table
+  (var index 1)
   (each [_ row (ipairs board)]
-    (let [(template count) (string.gsub row "x" "%%d")]
-      (if (> count 0)
+    (let [(row-template slots) (string.gsub row "x" "%%d")]
+      (if (> slots 0)
         (do
-          (set total-count (+ total-count count)) ; where i need that magic number on first iteration
-          (print (string.format template (select total-count (table.unpack moves)))))
-        (print row)))))
-; `select` above does NOT do what i thought it did.
-; i thought it would return the first x values given (select x values)
-; instead it returns the rest of the table having discarded the first x values
-; i think that `pick-values` probably does what i thought `select` does
+          (let [offset (+ index slots)
+                myslice (slice moves index offset)]
+						(print (string.format row-template (table.unpack myslice)))
+						(set index offset)))
+        (print row))))
+  (print (.. "Stage: " (string-upper (. (flip stages) game.stage))))
+  (print (.. "Player " game.player "'s turn:")))
 
 
-; these are the only moves that are valid
-; i am somewhat bothered by all the wasted space
-; by 2-3A and 5-6A e.g.
-; Incidentally these are all in order of appearance
-; so when you find a match,
-; you can also update that index of `moves` to the current player number
-(local valid-spaces [
-  "1A" "4A" "7A"
-  "2B" "4B" "6B"
-  "3C" "4C" "5C"
-  "1D" "2D" "3D"
-  "5D" "6D" "7D"
-  "3E" "4E" "5E"
-  "2F" "4F" "5F"
-  "1G" "4G" "7G"
-])
 ; add the inverse of each valid move
 ; e.g. 1A = A1
 (fn add-reverse-moves []
-  (let [reversed (icollect [_ v (ipairs valid-spaces)] (string.reverse v))]
+  (let [reversed (icollect [_ v (ipairs const.spaces)] (string.reverse v))]
     (each [_ v (ipairs reversed)]
-      (table.insert valid-spaces v))))
+      (table.insert const.spaces v)))) ;; oh nooooo i'm mutating a const????
 (add-reverse-moves)
 
 
 ; does the move exist within the domain of valid spaces
-(fn space-exists? [m] (contains valid-spaces (string.upper m)))
+(fn space-exists? [m] (contains const.spaces (string.upper m)))
+
 
-; return the numerical index of a "A1" formatted move
+; return the numerical index (1-24) of a [A-Za-z0-9] formatted move
 (fn index-of-move [m]
-    (let [ upper (string.upper m)
-           rev   (string.reverse upper)
-           idx   (head (icollect [i v (ipairs valid-spaces)]
-                         (if (or (= v upper) (= v rev)) i)))
-         ]
+    (let [upper (string.upper m)
+          rev   (string.reverse upper)
+          idx   (head (icollect [i v (ipairs const.spaces)]
+                        (if (or (= v upper) (= v rev)) i)))]
          idx))
 
-; is the space represented by a move ("A1") unoccupied?
+; is the space represented by a [A-Za-z0-9] move unoccupied?
 (fn space-is-unoccupied? [m]
-  (let [unoccupied? 0]
+  (let [unoccupied? 0] ; i.e. is move equal to 0
     (= unoccupied? (. moves (index-of-move m)))))
 
+
+(fn space-is-occupied-by-opponent? [m]
+	(let [opponent (if (= game.player 1) 2 1)]
+    (= opponent (. moves (index-of-move m)))))
+
+
+
 ; is this a legal move?
 ; TODO: maybe some functional error handling here?
 ;   https://mostly-adequate.gitbook.io/mostly-adequate-guide/ch08#pure-error-handling
@@ -237,30 +125,34 @@
   (or
     (and
       (= stages.placing game.stage)
-      (or (space-exists? move) (print "That space does not exist!\nHint: 1a 1A A1 a1 are all valid moves."))
-      (or (space-is-unoccupied? move) (print "That space is occupied!"))))
+      (or (space-exists? move)
+          (print "That space does not exist!\nHint: 1a 1A A1 a1 are all equal moves."))
+      (or (space-is-unoccupied? move)
+          (print "That space is occupied!")))
     (and
       ;; TODO: add capturing phase
       (= stages.capturing game.stage)
+			(or (space-is-occupied-by-opponent? move)
+          (print "Choose an opponent's piece to remove."))
       )
     (and
       ;; TODO: add flying phase
       (= stages.flying game.stage)
       )
+    )
   )
 
 
 
 ; get player input
 (fn get-move []
-  (print (.. "Player " game.player "'s turn:"))
   (io.read))
 
 
 (fn main []
   ;; game loop
   (while (not (= game.stage stages.complete))
-    (print-board board moves)
+    (print-board const.board moves)
 
     ;; validation loop
     (var is-valid false)
@@ -268,14 +160,16 @@
     (while (not is-valid)
       (set move (get-move))
       (set is-valid (valid-move? move))
-      (if (not is-valid)
-        (print "Try again.")
-        (do
-          (print (.. "You chose " move))
-          (tset moves (index-of-move move) game.player)
-          (game:update move)
+      (let [idx (index-of-move move)]
+        (if (not is-valid)
+          (print "Try again.")
+          (do
+            (print (.. "You chose " move))
+            (tset moves idx game.player)
+            (game:update idx)
+            )
           )
-      )
+        )
     )
   )
 )