add diamond

config.json

@@ -354,6 +354,14 @@
         "prerequisites": [],
         "difficulty": 4
       },
+      {
+        "slug": "diamond",
+        "name": "Diamond",
+        "uuid": "a3ea5637-c295-40ee-9ebf-a64268c60c77",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 4
+      },
       {
         "slug": "isbn-verifier",
         "name": "ISBN Verifier",

exercises/practice/diamond/.busted

@@ -0,0 +1,5 @@
+return {
+  default = {
+    ROOT = { '.' }
+  }
+}

exercises/practice/diamond/.docs/instructions.md

@@ -0,0 +1,52 @@
+# Instructions
+
+The diamond kata takes as its input a letter, and outputs it in a diamond shape.
+Given a letter, it prints a diamond starting with 'A', with the supplied letter at the widest point.
+
+## Requirements
+
+- The first row contains one 'A'.
+- The last row contains one 'A'.
+- All rows, except the first and last, have exactly two identical letters.
+- All rows have as many trailing spaces as leading spaces. (This might be 0).
+- The diamond is horizontally symmetric.
+- The diamond is vertically symmetric.
+- The diamond has a square shape (width equals height).
+- The letters form a diamond shape.
+- The top half has the letters in ascending order.
+- The bottom half has the letters in descending order.
+- The four corners (containing the spaces) are triangles.
+
+## Examples
+
+In the following examples, spaces are indicated by `·` characters.
+
+Diamond for letter 'A':
+
+```text
+A
+```
+
+Diamond for letter 'C':
+
+```text
+··A··
+·B·B·
+C···C
+·B·B·
+··A··
+```
+
+Diamond for letter 'E':
+
+```text
+····A····
+···B·B···
+··C···C··
+·D·····D·
+E·······E
+·D·····D·
+··C···C··
+···B·B···
+····A····
+```

exercises/practice/diamond/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "BNAndras"
+  ],
+  "files": {
+    "solution": [
+      "diamond.moon"
+    ],
+    "test": [
+      "diamond_spec.moon"
+    ],
+    "example": [
+      ".meta/example.moon"
+    ]
+  },
+  "blurb": "Given a letter, print a diamond starting with 'A' with the supplied letter at the widest point.",
+  "source": "Seb Rose",
+  "source_url": "https://web.archive.org/web/20220807163751/http://claysnow.co.uk/recycling-tests-in-tdd/"
+}

exercises/practice/diamond/.meta/example.moon

@@ -0,0 +1,25 @@
+{
+  rows: (letter) ->
+    return {'A'} if letter == 'A'
+
+    first = string.byte 'A'
+    last = string.byte letter
+    lines = last - first + 1
+    diamond = {}
+
+    for i = 0, lines - 1
+      symbol = string.char first + i
+      outerPadding = string.rep ' ', lines - 1 - i
+      line = if i == 0
+        outerPadding .. symbol .. outerPadding
+      else
+        innerPadding = string.rep ' ', 2 * i - 1
+        outerPadding .. symbol .. innerPadding .. symbol .. outerPadding
+      table.insert diamond, line
+
+    -- flip the diamond
+    for i = lines - 1, 1, -1
+      table.insert diamond, diamond[i]
+
+    diamond
+}

exercises/practice/diamond/.meta/spec_generator.moon

@@ -0,0 +1,16 @@
+{
+  module_name: 'Diamond'
+
+  generate_test: (case, level) ->
+    lines = {}
+    table.insert lines, "result = Diamond.#{case.property} #{quote case.input.letter}"
+
+    rows = [indent quote(row), level + 1 for row in *case.expected]
+    table.insert rows, 1, '{'
+    table.insert rows, indent('}', level)
+
+    table.insert lines, "expected = #{table.concat rows, '\n'}"
+    table.insert lines, "assert.are.same expected, result"
+
+    table.concat [indent line, level for line in *lines], '\n'
+}

exercises/practice/diamond/.meta/tests.toml

@@ -0,0 +1,25 @@
+# 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.
+
+[202fb4cc-6a38-4883-9193-a29d5cb92076]
+description = "Degenerate case with a single 'A' row"
+
+[bd6a6d78-9302-42e9-8f60-ac1461e9abae]
+description = "Degenerate case with no row containing 3 distinct groups of spaces"
+
+[af8efb49-14ed-447f-8944-4cc59ce3fd76]
+description = "Smallest non-degenerate case with odd diamond side length"
+
+[e0c19a95-9888-4d05-86a0-fa81b9e70d1d]
+description = "Smallest non-degenerate case with even diamond side length"
+
+[82ea9aa9-4c0e-442a-b07e-40204e925944]
+description = "Largest possible diamond"

exercises/practice/diamond/diamond.moon

@@ -0,0 +1,4 @@
+{
+  rows: (letter) ->
+    error 'Implement me!'
+}

exercises/practice/diamond/diamond_spec.moon

@@ -0,0 +1,99 @@
+Diamond = require 'diamond'
+
+describe 'diamond', ->
+  it "Degenerate case with a single 'A' row", ->
+    result = Diamond.rows 'A'
+    expected = {
+      'A'
+    }
+    assert.are.same expected, result
+
+  pending 'Degenerate case with no row containing 3 distinct groups of spaces', ->
+    result = Diamond.rows 'B'
+    expected = {
+      ' A '
+      'B B'
+      ' A '
+    }
+    assert.are.same expected, result
+
+  pending 'Smallest non-degenerate case with odd diamond side length', ->
+    result = Diamond.rows 'C'
+    expected = {
+      '  A  '
+      ' B B '
+      'C   C'
+      ' B B '
+      '  A  '
+    }
+    assert.are.same expected, result
+
+  pending 'Smallest non-degenerate case with even diamond side length', ->
+    result = Diamond.rows 'D'
+    expected = {
+      '   A   '
+      '  B B  '
+      ' C   C '
+      'D     D'
+      ' C   C '
+      '  B B  '
+      '   A   '
+    }
+    assert.are.same expected, result
+
+  pending 'Largest possible diamond', ->
+    result = Diamond.rows 'Z'
+    expected = {
+      '                         A                         '
+      '                        B B                        '
+      '                       C   C                       '
+      '                      D     D                      '
+      '                     E       E                     '
+      '                    F         F                    '
+      '                   G           G                   '
+      '                  H             H                  '
+      '                 I               I                 '
+      '                J                 J                '
+      '               K                   K               '
+      '              L                     L              '
+      '             M                       M             '
+      '            N                         N            '
+      '           O                           O           '
+      '          P                             P          '
+      '         Q                               Q         '
+      '        R                                 R        '
+      '       S                                   S       '
+      '      T                                     T      '
+      '     U                                       U     '
+      '    V                                         V    '
+      '   W                                           W   '
+      '  X                                             X  '
+      ' Y                                               Y '
+      'Z                                                 Z'
+      ' Y                                               Y '
+      '  X                                             X  '
+      '   W                                           W   '
+      '    V                                         V    '
+      '     U                                       U     '
+      '      T                                     T      '
+      '       S                                   S       '
+      '        R                                 R        '
+      '         Q                               Q         '
+      '          P                             P          '
+      '           O                           O           '
+      '            N                         N            '
+      '             M                       M             '
+      '              L                     L              '
+      '               K                   K               '
+      '                J                 J                '
+      '                 I               I                 '
+      '                  H             H                  '
+      '                   G           G                   '
+      '                    F         F                    '
+      '                     E       E                     '
+      '                      D     D                      '
+      '                       C   C                       '
+      '                        B B                        '
+      '                         A                         '
+    }
+    assert.are.same expected, result