Create an assessment directory

I've been doing a few take-home assessment recently, all of which I've attempted
to solve using Haskell. I'm having a good time, and I'm noticing strong and weak
points with my Haskell programming. I always attempt to apply any feedback a
reviewer gives me, and I'm storing my first drafts, second attempts, and
feedback here for now.

This recently attempt was for a role at Jane Street.

1 files changed, 80 insertions, 0 deletions

diff --git a/assessments/dotted-squares/Spec.hs b/assessments/dotted-squares/Spec.hs
new file mode 100644
index 000000000000..b5d604085b9b
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+++ b/assessments/dotted-squares/Spec.hs
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+--------------------------------------------------------------------------------
+module Spec where
+--------------------------------------------------------------------------------
+import Test.Hspec
+import Main hiding (main)
+import qualified Data.HashSet as HS
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = hspec $ do
+  describe "dotted-squares" $ do
+    describe "parseInput" $ do
+      it "works as expected" $ do
+        input <- readFile "input-a.txt"
+        parseInput input `shouldBe` Just (Game mempty [ mkLine (Point 0 0) (Point 1 0)
+                                                      , mkLine (Point 0 0) (Point 0 1)
+                                                      ])
+
+      it "fails when the game has too many user moves" $ do
+        input <- readFile "too-many-moves.txt"
+        parseInput input `shouldBe` Nothing
+
+      it "fails when the game has too few user moves" $ do
+        input <- readFile "too-few-moves.txt"
+        parseInput input `shouldBe` Nothing
+
+    describe "shiftLine" $ do
+      let horizontal = mkLineDir 1 1 DirRight
+          vertical   = mkLineDir 1 1 DirUp
+      it "can move a horizontal line up" $
+        shiftLine DirUp horizontal `shouldBe` mkLineDir 1 2 DirRight
+      it "can move a horizontal line down" $
+        shiftLine DirDown horizontal `shouldBe` mkLineDir 1 0 DirRight
+      it "can move a horizontal line left" $
+        shiftLine DirLeft horizontal `shouldBe` mkLineDir 0 1 DirRight
+      it "can move a horizontal line right" $
+        shiftLine DirRight horizontal `shouldBe` mkLineDir 2 1 DirRight
+      it "can move a vertical line up" $
+        shiftLine DirUp vertical `shouldBe` mkLineDir 1 2 DirUp
+      it "can move a vertical line down" $
+        shiftLine DirDown vertical `shouldBe` mkLineDir 1 0 DirUp
+      it "can move a vertical line left" $
+        shiftLine DirLeft vertical `shouldBe` mkLineDir 0 1 DirUp
+      it "can move a vertical line right" $
+        shiftLine DirRight vertical `shouldBe` mkLineDir 2 1 DirUp
+
+    describe "rotateLine" $ do
+      let horizontal = mkLineDir 1 1 DirRight -- 1,1;2,1
+          vertical   = mkLineDir 1 1 DirUp    -- 1,1;1,2
+      it "can rotate a horizontal line CW anchored at its beginning" $
+        rotateLine Beg CW horizontal `shouldBe` mkLineDir 1 1 DirDown
+      it "can rotate a horizontal line CCW anchored at its beginning" $
+        rotateLine Beg CCW horizontal `shouldBe` mkLineDir 1 1 DirUp
+      it "can rotate a horizontal line CW anchored at its end" $
+        rotateLine End CW horizontal `shouldBe` mkLineDir 2 1 DirUp
+      it "can rotate a horizontal line CCW anchored at its end" $
+        rotateLine End CCW horizontal `shouldBe` mkLineDir 2 1 DirDown
+
+      it "can rotate a vertical line CW anchored at its beginning" $
+        rotateLine Beg CW vertical `shouldBe` mkLineDir 1 1 DirRight
+      it "can rotate a vertical line CCW anchored at its beginning" $
+        rotateLine Beg CCW vertical `shouldBe` mkLineDir 1 1 DirLeft
+      it "can rotate a vertical line CW anchored at its end" $
+        rotateLine End CW vertical `shouldBe` mkLineDir 1 2 DirLeft
+      it "can rotate a vertical line CCW anchored at its end" $
+        rotateLine End CCW vertical `shouldBe` mkLineDir 1 2 DirRight
+
+    describe "closesAnySquare" $ do
+      let threeSides = [ (0, 0, DirRight)
+                       , (0, 0, DirUp)
+                       , (0, 1, DirRight)
+                       ]
+                       |> fmap (\(x, y, dir) -> mkLineDir x y dir)
+                       |> HS.fromList
+      it "returns true the line we supply makes a square" $
+        closesAnySquare threeSides (mkLineDir 1 1 DirDown) `shouldBe` True
+      it "returns false the line we supply doesn't make a square" $
+        closesAnySquare threeSides (mkLineDir 1 1 DirUp) `shouldBe` False
+      it "returns false when we have no existing lines" $
+        closesAnySquare mempty (mkLineDir 1 1 DirUp) `shouldBe` False