Add all-your-base exercise (#343)

* Add all-your-base exercise

* change implementation to just a single function

Author: glennj

config.json

@@ -730,6 +730,14 @@
         "practices": [],
         "prerequisites": [],
         "difficulty": 5
+      },
+      {
+        "slug": "all-your-base",
+        "name": "All Your Base",
+        "uuid": "b3bfbbd9-a0f4-4cbf-848b-f889bb0241a0",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 3
       }
     ]
   },

exercises/practice/all-your-base/.docs/instructions.md

@@ -0,0 +1,28 @@
+# Instructions
+
+Convert a sequence of digits in one base, representing a number, into a sequence of digits in another base, representing the same number.
+
+~~~~exercism/note
+Try to implement the conversion yourself.
+Do not use something else to perform the conversion for you.
+~~~~
+
+## About [Positional Notation][positional-notation]
+
+In positional notation, a number in base **b** can be understood as a linear combination of powers of **b**.
+
+The number 42, _in base 10_, means:
+
+`(4 × 10¹) + (2 × 10⁰)`
+
+The number 101010, _in base 2_, means:
+
+`(1 × 2⁵) + (0 × 2⁴) + (1 × 2³) + (0 × 2²) + (1 × 2¹) + (0 × 2⁰)`
+
+The number 1120, _in base 3_, means:
+
+`(1 × 3³) + (1 × 3²) + (2 × 3¹) + (0 × 3⁰)`
+
+_Yes. Those three numbers above are exactly the same. Congratulations!_
+
+[positional-notation]: https://en.wikipedia.org/wiki/Positional_notation

exercises/practice/all-your-base/.docs/introduction.md

@@ -0,0 +1,8 @@
+# Introduction
+
+You've just been hired as professor of mathematics.
+Your first week went well, but something is off in your second week.
+The problem is that every answer given by your students is wrong!
+Luckily, your math skills have allowed you to identify the problem: the student answers _are_ correct, but they're all in base 2 (binary)!
+Amazingly, it turns out that each week, the students use a different base.
+To help you quickly verify the student answers, you'll be building a tool to translate between bases.

exercises/practice/all-your-base/.meta/config.json

@@ -0,0 +1,17 @@
+{
+  "authors": [
+    "glennj"
+  ],
+  "files": {
+    "solution": [
+      "all-your-base.coffee"
+    ],
+    "test": [
+      "all-your-base.spec.coffee"
+    ],
+    "example": [
+      ".meta/example.coffee"
+    ]
+  },
+  "blurb": "Convert a number, represented as a sequence of digits in one base, to any other base."
+}

exercises/practice/all-your-base/.meta/example.coffee

@@ -0,0 +1,20 @@
+allYourBase = ({inputBase, outputBase, digits}) ->
+  throw new Error "input base must be >= 2" unless inputBase >= 2
+  throw new Error "output base must be >= 2" unless outputBase >= 2
+
+  if digits.some ((d) => d < 0 or d >= inputBase)
+    throw new Error "all digits must satisfy 0 <= d < input base"
+
+  decimal = digits.reduce ((dec, d) => dec * inputBase + d), 0
+
+  if decimal is 0
+    [0]
+  else
+    outputDigits = []
+    while decimal > 0
+      outputDigits.unshift decimal % outputBase
+      decimal //= outputBase
+    outputDigits
+
+
+module.exports = allYourBase

exercises/practice/all-your-base/.meta/tests.toml

@@ -0,0 +1,73 @@
+# 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.
+
+[5ce422f9-7a4b-4f44-ad29-49c67cb32d2c]
+description = "single bit one to decimal"
+
+[0cc3fea8-bb79-46ac-a2ab-5a2c93051033]
+description = "binary to single decimal"
+
+[f12db0f9-0d3d-42c2-b3ba-e38cb375a2b8]
+description = "single decimal to binary"
+
+[2c45cf54-6da3-4748-9733-5a3c765d925b]
+description = "binary to multiple decimal"
+
+[65ddb8b4-8899-4fcc-8618-181b2cf0002d]
+description = "decimal to binary"
+
+[8d418419-02a7-4824-8b7a-352d33c6987e]
+description = "trinary to hexadecimal"
+
+[d3901c80-8190-41b9-bd86-38d988efa956]
+description = "hexadecimal to trinary"
+
+[5d42f85e-21ad-41bd-b9be-a3e8e4258bbf]
+description = "15-bit integer"
+
+[d68788f7-66dd-43f8-a543-f15b6d233f83]
+description = "empty list"
+
+[5e27e8da-5862-4c5f-b2a9-26c0382b6be7]
+description = "single zero"
+
+[2e1c2573-77e4-4b9c-8517-6c56c5bcfdf2]
+description = "multiple zeros"
+
+[3530cd9f-8d6d-43f5-bc6e-b30b1db9629b]
+description = "leading zeros"
+
+[a6b476a1-1901-4f2a-92c4-4d91917ae023]
+description = "input base is one"
+
+[e21a693a-7a69-450b-b393-27415c26a016]
+description = "input base is zero"
+
+[54a23be5-d99e-41cc-88e0-a650ffe5fcc2]
+description = "input base is negative"
+
+[9eccf60c-dcc9-407b-95d8-c37b8be56bb6]
+description = "negative digit"
+
+[232fa4a5-e761-4939-ba0c-ed046cd0676a]
+description = "invalid positive digit"
+
+[14238f95-45da-41dc-95ce-18f860b30ad3]
+description = "output base is one"
+
+[73dac367-da5c-4a37-95fe-c87fad0a4047]
+description = "output base is zero"
+
+[13f81f42-ff53-4e24-89d9-37603a48ebd9]
+description = "output base is negative"
+
+[0e6c895d-8a5d-4868-a345-309d094cfe8d]
+description = "both bases are negative"

exercises/practice/all-your-base/all-your-base.coffee

@@ -0,0 +1,3 @@
+allYourBase = (args) ->
+
+module.exports = allYourBase

exercises/practice/all-your-base/all-your-base.spec.coffee

@@ -0,0 +1,191 @@
+allYourBase = require './all-your-base'
+
+describe "AllYourBase", -> 
+  it "single bit one to decimal", ->
+    actual = allYourBase {
+      inputBase: 2,
+      outputBase: 10,
+      digits: [1]
+    }
+    expected = [1]
+    expect(actual).toEqual expected
+
+  xit "binary to single decimal", ->
+    actual = allYourBase {
+      inputBase: 2,
+      outputBase: 10,
+      digits: [1, 0, 1]
+    }
+    expected = [5]
+    expect(actual).toEqual expected
+
+  xit "single decimal to binary", ->
+    actual = allYourBase {
+      inputBase: 10,
+      outputBase: 2,
+      digits: [5]
+    }
+    expected = [1, 0, 1]
+    expect(actual).toEqual expected
+
+  xit "binary to multiple decimal", ->
+    actual = allYourBase {
+      inputBase: 2,
+      outputBase: 10,
+      digits: [1, 0, 1, 0, 1, 0]
+    }
+    expected = [4, 2]
+    expect(actual).toEqual expected
+
+  xit "decimal to binary", ->
+    actual = allYourBase {
+      inputBase: 10,
+      outputBase: 2,
+      digits: [4, 2]
+    }
+    expected = [1, 0, 1, 0, 1, 0]
+    expect(actual).toEqual expected
+
+  xit "trinary to hexadecimal", ->
+    actual = allYourBase {
+      inputBase: 3,
+      outputBase: 16,
+      digits: [1, 1, 2, 0]
+    }
+    expected = [2, 10]
+    expect(actual).toEqual expected
+
+  xit "hexadecimal to trinary", ->
+    actual = allYourBase {
+      inputBase: 16,
+      outputBase: 3,
+      digits: [2, 10]
+    }
+    expected = [1, 1, 2, 0]
+    expect(actual).toEqual expected
+
+  xit "15-bit integer", ->
+    actual = allYourBase {
+      inputBase: 97,
+      outputBase: 73,
+      digits: [3, 46, 60]
+    }
+    expected = [6, 10, 45]
+    expect(actual).toEqual expected
+
+  xit "empty list", ->
+    actual = allYourBase {
+      inputBase: 2,
+      outputBase: 10,
+      digits: []
+    }
+    expected = [0]
+    expect(actual).toEqual expected
+
+  xit "single zero", ->
+    actual = allYourBase {
+      inputBase: 10,
+      outputBase: 2,
+      digits: [0]
+    }
+    expected = [0]
+    expect(actual).toEqual expected
+
+  xit "multiple zeros", ->
+    actual = allYourBase {
+      inputBase: 10,
+      outputBase: 2,
+      digits: [0, 0, 0]
+    }
+    expected = [0]
+    expect(actual).toEqual expected
+
+  xit "leading zeros", ->
+    actual = allYourBase {
+      inputBase: 7,
+      outputBase: 10,
+      digits: [0, 6, 0]
+    }
+    expected = [4, 2]
+    expect(actual).toEqual expected
+
+  xit "input base is one", ->
+    expect ->
+      allYourBase {
+        inputBase: 1,
+        outputBase: 10,
+        digits: [0]
+      }
+    .toThrow new Error "input base must be >= 2"
+
+  xit "input base is zero", ->
+    expect ->
+      allYourBase {
+        inputBase: 0,
+        outputBase: 10,
+        digits: []
+      }
+    .toThrow new Error "input base must be >= 2"
+
+  xit "input base is negative", ->
+    expect ->
+      allYourBase {
+        inputBase: -2,
+        outputBase: 10,
+        digits: [0]
+      }
+    .toThrow new Error "input base must be >= 2"
+
+  xit "negative digit", ->
+    expect ->
+      allYourBase {
+        inputBase: 2,
+        outputBase: 10,
+        digits: [1, -1, 1, 0, 1, 0]
+      }
+    .toThrow new Error "all digits must satisfy 0 <= d < input base"
+
+  xit "invalid positive digit", ->
+    expect ->
+      allYourBase {
+        inputBase: 2,
+        outputBase: 10,
+        digits: [1, 2, 1, 0, 1, 0]
+      }
+    .toThrow new Error "all digits must satisfy 0 <= d < input base"
+
+  xit "output base is one", ->
+    expect ->
+      allYourBase {
+        inputBase: 2,
+        outputBase: 1,
+        digits: [1, 0, 1, 0, 1, 0]
+      }
+    .toThrow new Error "output base must be >= 2"
+
+  xit "output base is zero", ->
+    expect ->
+      allYourBase {
+        inputBase: 10,
+        outputBase: 0,
+        digits: [7]
+      }
+    .toThrow new Error "output base must be >= 2"
+
+  xit "output base is negative", ->
+    expect ->
+      allYourBase {
+        inputBase: 2,
+        outputBase: -7,
+        digits: [1]
+      }
+    .toThrow new Error "output base must be >= 2"
+
+  xit "both bases are negative", ->
+    expect ->
+      allYourBase {
+        inputBase: -2,
+        outputBase: -7,
+        digits: [1]
+      }
+    .toThrow new Error "input base must be >= 2"