Merge pull request #68 from masters3d/Swift-2.0

update binary to return Optionals
exercism · Sep 16, 2015 · caac989 · caac989
2 parents eb4ac84 + f7f5132
commit caac989
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Showing 2 changed files with 31 additions and 12 deletions.
diff --git a/binary/BinaryExample.swift b/binary/BinaryExample.swift
@@ -7,21 +7,26 @@ struct Binary {
 
     var toDecimal:Int {get {return Int(UIntValue)}}
 
-    private func bi2Uint(input:String) -> UInt{
+    private func bi2Uint(input:String) -> UInt?{
         let orderedInput = Array(input.characters.reverse())
         var tempUInt:UInt = 0
         for (inx,each) in orderedInput.enumerate(){
             if each == "1" {
                 tempUInt += UInt(0x1 << inx)
             }
             if (each != "0" && each != "1") {
-                return 0
+                return nil
             }
         }
         return tempUInt
     }
 
-    init(_ input:String){
-        self.UIntValue = bi2Uint(input)
+    init?(_ input:String){
+        if bi2Uint(input) != nil {
+        self.UIntValue = bi2Uint(input)!
+        } else {
+        return nil
+        }
+
     }
 }
diff --git a/binary/BinaryTest.swift b/binary/BinaryTest.swift
@@ -4,37 +4,51 @@ import XCTest
 
 class BinaryTests: XCTestCase {
 
+    func testBinary0IsDecimal0() {
+        XCTAssertEqual( 0, Binary("0")?.toDecimal)
+    }
+
     func testBinary1isDecimal1() {
-        XCTAssertEqual( 1, Binary("1").toDecimal)
+        XCTAssertEqual( 1, Binary("1")?.toDecimal)
     }
 
     func testBinary10isDecimal2() {
-        XCTAssertEqual( 2, Binary("10").toDecimal)
+        XCTAssertEqual( 2, Binary("10")?.toDecimal)
     }
 
     func testBinary11isDecimal3() {
-        XCTAssertEqual( 3, Binary("11").toDecimal)
+        XCTAssertEqual( 3, Binary("11")?.toDecimal)
     }
 
     func testBinary100isDecimal4() {
-        XCTAssertEqual( 4, Binary("100").toDecimal)
+        XCTAssertEqual( 4, Binary("100")?.toDecimal)
     }
 
     func testBinary1001isDecimal9() {
-        XCTAssertEqual( 9, Binary("1001").toDecimal)
+        XCTAssertEqual( 9, Binary("1001")?.toDecimal)
     }
 
     func testBinary11010isDecimal26() {
-        XCTAssertEqual( 26, Binary("11010").toDecimal)
+        XCTAssertEqual( 26, Binary("11010")?.toDecimal)
     }
 
     func testBinary10001101000isDecimal1128() {
-        XCTAssertEqual( 1128, Binary("10001101000").toDecimal)
+        XCTAssertEqual( 1128, Binary("10001101000")?.toDecimal)
+    }
+
+    func testBinaryIgnoresLeadingZeros() {
+        XCTAssertEqual( 31, Binary("000011111")?.toDecimal)
     }
 
     func testInvalidBinaryIsDecimal0() {
-        XCTAssertEqual( 0, Binary("carrot123").toDecimal)
+        XCTAssertNil ( Binary("carrot123")?.toDecimal)
     }
 
+    func testInvalidBinaryNumbers() {
+        XCTAssertNil ( Binary("012")?.toDecimal)
+        XCTAssertNil ( Binary("10nope")?.toDecimal)
+        XCTAssertNil ( Binary("nope10")?.toDecimal)
+
+    }
 
 }