Add secret-handshake (#176)

config.json

@@ -256,6 +256,14 @@
         "prerequisites": [],
         "difficulty": 3
       },
+      {
+        "slug": "secret-handshake",
+        "name": "Secret Handshake",
+        "uuid": "4afe24ca-c886-4bc8-8eea-2b2b2d00077e",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
+      },
       {
         "slug": "all-your-base",
         "name": "All Your Base",

exercises/practice/secret-handshake/.docs/instructions.md

@@ -0,0 +1,48 @@
+# Instructions
+
+Your task is to convert a number between 1 and 31 to a sequence of actions in the secret handshake.
+
+The sequence of actions is chosen by looking at the rightmost five digits of the number once it's been converted to binary.
+Start at the right-most digit and move left.
+
+The actions for each number place are:
+
+```plaintext
+00001 = wink
+00010 = double blink
+00100 = close your eyes
+01000 = jump
+10000 = Reverse the order of the operations in the secret handshake.
+```
+
+Let's use the number `9` as an example:
+
+- 9 in binary is `1001`.
+- The digit that is farthest to the right is 1, so the first action is `wink`.
+- Going left, the next digit is 0, so there is no double-blink.
+- Going left again, the next digit is 0, so you leave your eyes open.
+- Going left again, the next digit is 1, so you jump.
+
+That was the last digit, so the final code is:
+
+```plaintext
+wink, jump
+```
+
+Given the number 26, which is `11010` in binary, we get the following actions:
+
+- double blink
+- jump
+- reverse actions
+
+The secret handshake for 26 is therefore:
+
+```plaintext
+jump, double blink
+```
+
+~~~~exercism/note
+If you aren't sure what binary is or how it works, check out [this binary tutorial][intro-to-binary].
+
+[intro-to-binary]: https://medium.com/basecs/bits-bytes-building-with-binary-13cb4289aafa
+~~~~

exercises/practice/secret-handshake/.docs/introduction.md

@@ -0,0 +1,7 @@
+# Introduction
+
+You are starting a secret coding club with some friends and friends-of-friends.
+Not everyone knows each other, so you and your friends have decided to create a secret handshake that you can use to recognize that someone is a member.
+You don't want anyone who isn't in the know to be able to crack the code.
+
+You've designed the code so that one person says a number between 1 and 31, and the other person turns it into a series of actions.

exercises/practice/secret-handshake/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "keiravillekode"
+  ],
+  "files": {
+    "solution": [
+      "src/SecretHandshake.idr"
+    ],
+    "test": [
+      "test/src/Main.idr"
+    ],
+    "example": [
+      "example/SecretHandshake.idr"
+    ]
+  },
+  "blurb": "Given a decimal number, convert it to the appropriate sequence of events for a secret handshake.",
+  "source": "Bert, in Mary Poppins",
+  "source_url": "https://www.imdb.com/title/tt0058331/quotes/?item=qt0437047"
+}

exercises/practice/secret-handshake/.meta/tests.toml

@@ -0,0 +1,43 @@
+# This is an auto-generated file.
+#
+# Regenerating this file via `configlet sync` will:
+# - Recreate every `description` key/value pair
+# - Recreate every `reimplements` key/value pair, where they exist in problem-specifications
+# - Remove any `include = true` key/value pair (an omitted `include` key implies inclusion)
+# - Preserve any other key/value pair
+#
+# As user-added comments (using the # character) will be removed when this file
+# is regenerated, comments can be added via a `comment` key.
+
+[b8496fbd-6778-468c-8054-648d03c4bb23]
+description = "wink for 1"
+
+[83ec6c58-81a9-4fd1-bfaf-0160514fc0e3]
+description = "double blink for 10"
+
+[0e20e466-3519-4134-8082-5639d85fef71]
+description = "close your eyes for 100"
+
+[b339ddbb-88b7-4b7d-9b19-4134030d9ac0]
+description = "jump for 1000"
+
+[40499fb4-e60c-43d7-8b98-0de3ca44e0eb]
+description = "combine two actions"
+
+[9730cdd5-ef27-494b-afd3-5c91ad6c3d9d]
+description = "reverse two actions"
+
+[0b828205-51ca-45cd-90d5-f2506013f25f]
+description = "reversing one action gives the same action"
+
+[9949e2ac-6c9c-4330-b685-2089ab28b05f]
+description = "reversing no actions still gives no actions"
+
+[23fdca98-676b-4848-970d-cfed7be39f81]
+description = "all possible actions"
+
+[ae8fe006-d910-4d6f-be00-54b7c3799e79]
+description = "reverse all possible actions"
+
+[3d36da37-b31f-4cdb-a396-d93a2ee1c4a5]
+description = "do nothing for zero"

exercises/practice/secret-handshake/example/SecretHandshake.idr

@@ -0,0 +1,14 @@
+module SecretHandshake
+
+public export
+data Action = Wink | DoubleBlink | CloseYourEyes | Jump
+
+export
+commands : Int -> List Action
+commands number = loop commandList [] number
+  where commandList = [Wink, DoubleBlink, CloseYourEyes, Jump]
+        loop : List Action -> List Action -> Int -> List Action
+        loop [] suffix n = if n == 0 then reverse suffix
+                           else suffix
+        loop (x :: xs) suffix n = if mod n 2 == 1 then loop xs (x :: suffix) (div n 2)
+                                  else loop xs suffix (div n 2)

exercises/practice/secret-handshake/pack.toml

@@ -0,0 +1,10 @@
+[custom.all.secret-handshake]
+type = "local"
+path = "."
+ipkg = "secret-handshake.ipkg"
+test = "test/test.ipkg"
+
+[custom.all.secret-handshake-test]
+type = "local"
+path = "test"
+ipkg = "test.ipkg"

exercises/practice/secret-handshake/secret-handshake.ipkg

@@ -0,0 +1,3 @@
+package secret-handshake
+modules = SecretHandshake
+sourcedir = "src"

exercises/practice/secret-handshake/src/SecretHandshake.idr

@@ -0,0 +1,8 @@
+module SecretHandshake
+
+public export
+data Action = Wink | DoubleBlink | CloseYourEyes | Jump
+
+export
+commands : Int -> List Action
+commands number = ?commands_rhs

exercises/practice/secret-handshake/test/src/Main.idr

@@ -0,0 +1,45 @@
+module Main
+
+import System
+import Tester
+import Tester.Runner
+
+import SecretHandshake
+
+public export
+implementation Eq Action where
+  (==) Wink Wink = True
+  (==) DoubleBlink DoubleBlink = True
+  (==) CloseYourEyes CloseYourEyes = True
+  (==) Jump Jump = True
+  (==) _ _ = False
+
+public export
+implementation Show Action where
+  show Wink = "Wink"
+  show DoubleBlink = "DoubleBlink"
+  show CloseYourEyes = "CloseYourEyes"
+  show Jump = "Jump"
+
+tests : List Test
+tests =
+  [ test "wink for 1"                                  (assertEq (commands 1) [Wink])
+  , test "double blink for 10"                         (assertEq (commands 2) [DoubleBlink])
+  , test "close your eyes for 100"                     (assertEq (commands 4) [CloseYourEyes])
+  , test "jump for 1000"                               (assertEq (commands 8) [Jump])
+  , test "combine two actions"                         (assertEq (commands 3) [Wink, DoubleBlink])
+  , test "reverse two actions"                         (assertEq (commands 19) [DoubleBlink, Wink])
+  , test "reversing one action gives the same action"  (assertEq (commands 24) [Jump])
+  , test "reversing no actions still gives no actions" (assertEq (commands 16) [])
+  , test "all possible actions"                        (assertEq (commands 15) [Wink, DoubleBlink, CloseYourEyes, Jump])
+  , test "reverse all possible actions"                (assertEq (commands 31) [Jump, CloseYourEyes, DoubleBlink, Wink])
+  , test "do nothing for zero"                         (assertEq (commands 0) [])
+  ]
+
+export
+main : IO ()
+main = do
+  success <- runTests tests
+  if success
+     then putStrLn "All tests passed"
+     else exitFailure

exercises/practice/secret-handshake/test/test.ipkg

@@ -0,0 +1,6 @@
+package secret-handshake-test
+depends = secret-handshake
+  , tester
+main = Main
+executable = "secret-handshake-test"
+sourcedir = "src"

generators/exercises/secret_handshake.py

@@ -0,0 +1,30 @@
+
+HEADER = """
+public export
+implementation Eq Action where
+  (==) Wink Wink = True
+  (==) DoubleBlink DoubleBlink = True
+  (==) CloseYourEyes CloseYourEyes = True
+  (==) Jump Jump = True
+  (==) _ _ = False
+
+public export
+implementation Show Action where
+  show Wink = "Wink"
+  show DoubleBlink = "DoubleBlink"
+  show CloseYourEyes = "CloseYourEyes"
+  show Jump = "Jump"
+"""
+
+def header():
+    return HEADER
+
+def generate_test(case):
+    def toActionList(strings):
+        return str(list(map(lambda str: str.title().replace(" ", ""), strings))).replace("'", "")
+
+    property = case["property"]
+    number = case["input"]["number"]
+    expected = toActionList(case["expected"])
+
+    return f'assertEq ({property} {number}) {expected}'