Update exercises batch 6 (#657)

* Update exercises batch 6

* Fix luhn

* Fix matrix

* Fix plugins

* Fix generator

exercises/practice/luhn/.meta/Sources/Luhn/LuhnExample.swift

@@ -1,51 +1,18 @@
 import Foundation
 
-struct Luhn {
-
-    var number: Int64 = 0
-    var numberString: String = ""
-    var addends: [Int] { return addendsFunc(numberString) }
-    var checksum: Int { return addends.reduce(0, +) }
-    var isValid: Bool = false
-
-    init(_ num: String ) {
-        self.numberString = num.replacingOccurrences(of: " ", with: "")
-        let num = Int64(numberString)
-        if self.numberString.utf16.count <= 1 {
-            self.isValid = false
-        } else if num == nil {
-            isValid = false
-        } else {
-            self.number = num!
-            isValid = checksum % 10 == 0
-        }
-    }
-
-    func addendsFunc(_ num: String) -> [Int] {
-        func oddIndexInt64Minus9( _ input: [Int]) -> [Int] {
-            var input = input
-            input = Array(input.reversed())
-            var tempArray: [Int] = []
-            for (inx, each) in input.enumerated() {
-                var tempEach: Int = each
-                if (inx+1) % 2 == 0 {
-                    tempEach *= 2
-                    if tempEach >= 10 {
-                        tempEach -= 9
-                    }
-                    tempArray.insert(tempEach, at: 0)
-                } else {
-                    tempArray.insert(tempEach, at: 0)
-                }
-            }
-            return tempArray
-        }
-        func char2Int(_ input: Character) -> Int {
-            let tempInt = Int(String(input)) ?? -1 // -1 = error
-            return tempInt
-        }
-
-        return oddIndexInt64Minus9(Array(num).map { char2Int($0) })
+func isValidLuhn(_ number: String) -> Bool {
+  var number = number
+  var sum = 0
+  var odd = true
+  number = number.replacingOccurrences(of:" ", with: "")
+  guard number.count > 1 else { return false }
+  for char in number.reversed() {
+    if let digit = Int(String(char)) {
+      sum += odd ? digit : digit < 5 ? digit * 2 : digit * 2 - 9
+      odd.toggle()
+    } else {
+      return false
     }
-
+  }
+  return sum % 10 == 0
 }

exercises/practice/luhn/.meta/config.json

@@ -11,7 +11,8 @@
     "lyuha",
     "nickkjordan",
     "robtimp",
-    "ThomasHaz"
+    "ThomasHaz",
+    "meatball133"
   ],
   "files": {
     "solution": [

exercises/practice/luhn/.meta/template.swift

@@ -0,0 +1,20 @@
+import XCTest
+@testable import {{exercise|camelCase}}
+class {{exercise|camelCase}}Tests: XCTestCase {
+    let runAll = Bool(ProcessInfo.processInfo.environment["RUNALL", default: "false"]) ?? false
+
+    {% for case in cases %}
+    {% if forloop.first -%}
+        func test{{case.description |camelCase }}() {
+    {% else -%}
+        func test{{case.description |camelCase }}() throws {
+        try XCTSkipIf(true && !runAll) // change true to false to run this test
+    {% endif -%}
+        {%- if case.expected -%}
+        XCTAssertTrue(isValidLuhn("{{case.input.value}}"))
+        {%- else -%}
+        XCTAssertFalse(isValidLuhn("{{case.input.value}}"))
+        {%- endif %}
+    }
+    {% endfor -%}
+}

exercises/practice/luhn/.meta/tests.toml

@@ -33,6 +33,9 @@ description = "invalid credit card"
 [20e67fad-2121-43ed-99a8-14b5b856adb9]
 description = "invalid long number with an even remainder"
 
+[7e7c9fc1-d994-457c-811e-d390d52fba5e]
+description = "invalid long number with a remainder divisible by 5"
+
 [ad2a0c5f-84ed-4e5b-95da-6011d6f4f0aa]
 description = "valid number with an even number of digits"
 
@@ -57,6 +60,12 @@ description = "more than a single zero is valid"
 [ab56fa80-5de8-4735-8a4a-14dae588663e]
 description = "input digit 9 is correctly converted to output digit 9"
 
+[b9887ee8-8337-46c5-bc45-3bcab51bc36f]
+description = "very long input is valid"
+
+[8a7c0e24-85ea-4154-9cf1-c2db90eabc08]
+description = "valid luhn with an odd number of digits and non zero first digit"
+
 [39a06a5a-5bad-4e0f-b215-b042d46209b1]
 description = "using ascii value for non-doubled non-digit isn't allowed"
 

exercises/practice/luhn/Package.swift

@@ -3,19 +3,19 @@
 import PackageDescription
 
 let package = Package(
-    name: "Luhn",
-    products: [
-        .library(
-            name: "Luhn",
-            targets: ["Luhn"]),
-    ],
-    dependencies: [],
-    targets: [
-        .target(
-            name: "Luhn",
-            dependencies: []),
-        .testTarget(
-            name: "LuhnTests",
-            dependencies: ["Luhn"]),
-    ]
+  name: "Luhn",
+  products: [
+    .library(
+      name: "Luhn",
+      targets: ["Luhn"])
+  ],
+  dependencies: [],
+  targets: [
+    .target(
+      name: "Luhn",
+      dependencies: []),
+    .testTarget(
+      name: "LuhnTests",
+      dependencies: ["Luhn"]),
+  ]
 )

exercises/practice/luhn/Sources/Luhn/Luhn.swift

@@ -1 +1,3 @@
-//Solution goes in Sources
+func isValidLuhn(_ number: String) -> Bool {
+  // Write your code for the 'Luhn' exercise in this file.
+}

exercises/practice/luhn/Tests/LuhnTests/LuhnTests.swift

@@ -1,70 +1,116 @@
 import XCTest
+
 @testable import Luhn
 
 class LuhnTests: XCTestCase {
+  let runAll = Bool(ProcessInfo.processInfo.environment["RUNALL", default: "false"]) ?? false
+
+  func testSingleDigitStringsCanNotBeValid() {
+    XCTAssertFalse(isValidLuhn("1"))
+  }
+
+  func testASingleZeroIsInvalid() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("0"))
+  }
+
+  func testASimpleValidSinThatRemainsValidIfReversed() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("059"))
+  }
+
+  func testASimpleValidSinThatBecomesInvalidIfReversed() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("59"))
+  }
+
+  func testAValidCanadianSin() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("055 444 285"))
+  }
+
+  func testInvalidCanadianSin() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("055 444 286"))
+  }
+
+  func testInvalidCreditCard() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("8273 1232 7352 0569"))
+  }
+
+  func testInvalidLongNumberWithAnEvenRemainder() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("1 2345 6789 1234 5678 9012"))
+  }
+
+  func testInvalidLongNumberWithARemainderDivisibleBy5() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("1 2345 6789 1234 5678 9013"))
+  }
+
+  func testValidNumberWithAnEvenNumberOfDigits() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("095 245 88"))
+  }
+
+  func testValidNumberWithAnOddNumberOfSpaces() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("234 567 891 234"))
+  }
+
+  func testValidStringsWithANonDigitAddedAtTheEndBecomeInvalid() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("059a"))
+  }
+
+  func testValidStringsWithPunctuationIncludedBecomeInvalid() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("055-444-285"))
+  }
+
+  func testValidStringsWithSymbolsIncludedBecomeInvalid() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("055# 444$ 285"))
+  }
+
+  func testSingleZeroWithSpaceIsInvalid() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn(" 0"))
+  }
+
+  func testMoreThanASingleZeroIsValid() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("0000 0"))
+  }
+
+  func testInputDigit9IsCorrectlyConvertedToOutputDigit9() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("091"))
+  }
+
+  func testVeryLongInputIsValid() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("9999999999 9999999999 9999999999 9999999999"))
+  }
+
+  func testValidLuhnWithAnOddNumberOfDigitsAndNonZeroFirstDigit() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertTrue(isValidLuhn("109"))
+  }
+
+  func testUsingAsciiValueForNonDoubledNonDigitIsntAllowed() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("055b 444 285"))
+  }
+
+  func testUsingAsciiValueForDoubledNonDigitIsntAllowed() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn(":9"))
+  }
 
-    func testSingleDigitInvalid() {
-        let luhn = Luhn("1")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testSingleZeroInvalid() {
-        let luhn = Luhn("0")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testSimpleReversableValid() {
-        let luhn = Luhn("059")
-        XCTAssertEqual (true, luhn.isValid)
-    }
-
-    func testSimpleIrreversableValid() {
-        let luhn = Luhn("59")
-        XCTAssertEqual (true, luhn.isValid)
-    }
-
-    func testCanadianValid() {
-        let luhn = Luhn("055 444 285")
-        XCTAssertEqual (true, luhn.isValid)
-    }
-
-    func testCanadianInvalid() {
-        let luhn = Luhn("055 444 286")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testCreditCardInvalid() {
-        let luhn = Luhn("8273 1232 7352 0569")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testNonDigitInvalid() {
-        let luhn = Luhn("055a 444 285")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testPunctuationInvalid() {
-        let luhn = Luhn("055-444-285")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testSymbolsInvalid() {
-        let luhn = Luhn("055£ 444$ 285")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testZeroWithSpaceInvalid() {
-        let luhn = Luhn(" 0")
-        XCTAssertEqual (false, luhn.isValid)
-    }
-
-    func testMultipleZeroesValid() {
-        let luhn = Luhn("0000 0")
-        XCTAssertEqual (true, luhn.isValid)
-    }
-
-    func testInputNineOutputNine() {
-        let luhn = Luhn("091")
-        XCTAssertEqual (true, luhn.isValid)
-    }
+  func testNonNumericNonSpaceCharInTheMiddleWithASumThatsDivisibleBy10IsntAllowed() throws {
+    try XCTSkipIf(true && !runAll)  // change true to false to run this test
+    XCTAssertFalse(isValidLuhn("59%59"))
+  }
 }

exercises/practice/matching-brackets/.docs/instructions.md

@@ -1,3 +1,4 @@
 # Instructions
 
 Given a string containing brackets `[]`, braces `{}`, parentheses `()`, or any combination thereof, verify that any and all pairs are matched and nested correctly.
+The string may also contain other characters, which for the purposes of this exercise should be ignored.

exercises/practice/matching-brackets/.meta/Sources/MatchingBrackets/MatchingBracketsExample.swift

@@ -1,25 +1,26 @@
 struct MatchingBrackets {
 
-    private static let brackets: [Character: Character] = [
-        ")": "(",
-        "]": "[",
-        "}": "{"
-    ]
+  private static let brackets: [Character: Character] = [
+    ")": "(",
+    "]": "[",
+    "}": "{",
+  ]
 
-    static func paired(text: String) -> Bool {
-        var stack = [Character]()
+  static func paired(text: String) -> Bool {
+    var stack = [Character]()
 
-        for character in text {
-            if brackets.values.contains(character) {
-                stack.append(character)
-            } else if brackets.keys.contains(character) {
-                guard let last = stack.popLast(),
-                    last == brackets[character] else {
-                        return false
-                }
-            }
+    for character in text {
+      if brackets.values.contains(character) {
+        stack.append(character)
+      } else if brackets.keys.contains(character) {
+        guard let last = stack.popLast(),
+          last == brackets[character]
+        else {
+          return false
         }
-
-        return stack.isEmpty
+      }
     }
+
+    return stack.isEmpty
+  }
 }