Add proverb

config.json

@@ -188,6 +188,14 @@
           "math"
         ]
       },
+      {
+        "slug": "proverb",
+        "name": "Proverb",
+        "uuid": "c0c9c922-e1c7-4971-ac7f-efac2a25a63a",
+        "practices": [],
+        "prerequisites": [],
+        "difficulty": 2
+      },
       {
         "slug": "grains",
         "name": "Grains",

exercises/practice/proverb/.docs/instructions.md

@@ -0,0 +1,19 @@
+# Instructions
+
+For want of a horseshoe nail, a kingdom was lost, or so the saying goes.
+
+Given a list of inputs, generate the relevant proverb.
+For example, given the list `["nail", "shoe", "horse", "rider", "message", "battle", "kingdom"]`, you will output the full text of this proverbial rhyme:
+
+```text
+For want of a nail the shoe was lost.
+For want of a shoe the horse was lost.
+For want of a horse the rider was lost.
+For want of a rider the message was lost.
+For want of a message the battle was lost.
+For want of a battle the kingdom was lost.
+And all for the want of a nail.
+```
+
+Note that the list of inputs may vary; your solution should be able to handle lists of arbitrary length and content.
+No line of the output text should be a static, unchanging string; all should vary according to the input given.

exercises/practice/proverb/.meta/config.json

@@ -0,0 +1,19 @@
+{
+  "authors": [
+    "BNAndras"
+  ],
+  "files": {
+    "solution": [
+      "lib/proverb.dart"
+    ],
+    "test": [
+      "test/proverb_test.dart"
+    ],
+    "example": [
+      ".meta/lib/example.dart"
+    ]
+  },
+  "blurb": "For want of a horseshoe nail, a kingdom was lost, or so the saying goes. Output the full text of this proverbial rhyme.",
+  "source": "Wikipedia",
+  "source_url": "https://en.wikipedia.org/wiki/For_Want_of_a_Nail"
+}

exercises/practice/proverb/.meta/lib/example.dart

@@ -0,0 +1,15 @@
+class Proverb {
+  String recite(List<String> pieces) {
+    if (pieces.isEmpty) {
+      return '';
+    }
+
+    final List<String> results = [];
+    for (int i = 0; i < pieces.length - 1; i++) {
+      results.add('For want of a ${pieces[i]} the ${pieces[i + 1]} was lost.');
+    }
+    results.add('And all for the want of a ${pieces.first}.');
+
+    return results.join('\n');
+  }
+}

exercises/practice/proverb/.meta/tests.toml

@@ -0,0 +1,28 @@
+# 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.
+
+[e974b73e-7851-484f-8d6d-92e07fe742fc]
+description = "zero pieces"
+
+[2fcd5f5e-8b82-4e74-b51d-df28a5e0faa4]
+description = "one piece"
+
+[d9d0a8a1-d933-46e2-aa94-eecf679f4b0e]
+description = "two pieces"
+
+[c95ef757-5e94-4f0d-a6cb-d2083f5e5a83]
+description = "three pieces"
+
+[433fb91c-35a2-4d41-aeab-4de1e82b2126]
+description = "full proverb"
+
+[c1eefa5a-e8d9-41c7-91d4-99fab6d6b9f7]
+description = "four pieces modernized"

exercises/practice/proverb/analysis_options.yaml

@@ -0,0 +1,18 @@
+analyzer:
+  strong-mode:
+    implicit-casts: false
+    implicit-dynamic: false
+  errors:
+    unused_element:        error
+    unused_import:         error
+    unused_local_variable: error
+    dead_code:             error
+
+linter:
+  rules:
+    # Error Rules
+    - avoid_relative_lib_imports
+    - avoid_types_as_parameter_names
+    - literal_only_boolean_expressions
+    - no_adjacent_strings_in_list
+    - valid_regexps

exercises/practice/proverb/lib/proverb.dart

@@ -0,0 +1,3 @@
+class Proverb {
+  // Put your code here
+}

exercises/practice/proverb/pubspec.yaml

@@ -0,0 +1,5 @@
+name: 'proverb'
+environment:
+  sdk: '>=3.2.0 <4.0.0'
+dev_dependencies:
+  test: '<2.0.0'

exercises/practice/proverb/test/proverb_test.dart

@@ -0,0 +1,66 @@
+import 'package:proverb/proverb.dart';
+import 'package:test/test.dart';
+
+void main() {
+  final proverb = Proverb();
+
+  group('Proverb', () {
+    test('zero pieces', () {
+      List<String> pieces = [];
+      final result = proverb.recite(pieces);
+      final expected = "";
+      expect(result, equals(expected));
+    }, skip: false);
+
+    test('one piece', () {
+      final pieces = ["nail"];
+      final result = proverb.recite(pieces);
+      final expected = "And all for the want of a nail.";
+      expect(result, equals(expected));
+    }, skip: true);
+
+    test('two pieces', () {
+      final pieces = ["nail", "shoe"];
+      final result = proverb.recite(pieces);
+      final expected = '''
+For want of a nail the shoe was lost.
+And all for the want of a nail.''';
+      expect(result, equals(expected));
+    }, skip: true);
+
+    test('three pieces', () {
+      final pieces = ["nail", "shoe", "horse"];
+      final result = proverb.recite(pieces);
+      final expected = '''
+For want of a nail the shoe was lost.
+For want of a shoe the horse was lost.
+And all for the want of a nail.''';
+      expect(result, equals(expected));
+    }, skip: true);
+
+    test('full proverb', () {
+      final pieces = ["nail", "shoe", "horse", "rider", "message", "battle", "kingdom"];
+      final result = proverb.recite(pieces);
+      final expected = '''
+For want of a nail the shoe was lost.
+For want of a shoe the horse was lost.
+For want of a horse the rider was lost.
+For want of a rider the message was lost.
+For want of a message the battle was lost.
+For want of a battle the kingdom was lost.
+And all for the want of a nail.''';
+      expect(result, equals(expected));
+    }, skip: true);
+
+    test('four pieces modernized', () {
+      final pieces = ["pin", "gun", "soldier", "battle"];
+      final result = proverb.recite(pieces);
+      final expected = '''
+For want of a pin the gun was lost.
+For want of a gun the soldier was lost.
+For want of a soldier the battle was lost.
+And all for the want of a pin.''';
+      expect(result, equals(expected));
+    }, skip: true);
+  });
+}