Add SortedArray.firstIndex(of:) (like the standard library)

We follow the standard library and do _not_ deprecate index(of:) yet.

Author: ole

Sources/SortedArray.swift

@@ -252,7 +252,7 @@ extension SortedArray {
     /// Returns the first index where the specified value appears in the collection.
     ///
     /// - Complexity: O(_log(n)_), where _n_ is the size of the array.
-    public func index(of element: Element) -> Index? {
+    public func firstIndex(of element: Element) -> Index? {
         var range: Range<Index> = startIndex ..< endIndex
         var match: Index? = nil
         while case let .found(m) = search(for: element, in: range) {
@@ -274,6 +274,14 @@ extension SortedArray {
         return match
     }
 
+    /// Returns the first index where the specified value appears in the collection.
+    /// Old name for `firstIndex(of:)`.
+    /// - Seealso: `firstIndex(of:)`
+    @inlinable
+    public func index(of element: Element) -> Index? {
+        return firstIndex(of: element)
+    }
+
     /// Returns a Boolean value indicating whether the sequence contains the given element.
     ///
     /// - Complexity: O(_log(n)_), where _n_ is the size of the array.

Tests/SortedArrayTests/SortedArrayTests.swift

@@ -108,68 +108,74 @@ class SortedArrayTests: XCTestCase {
 
     func testIndexOfFindsElementInMiddle() {
         let sut = SortedArray(unsorted: ["a","z","r","k"])
-        let index = sut.index(of: "k")
+        let index = sut.firstIndex(of: "k")
         XCTAssertEqual(index, 1)
     }
 
     func testIndexOfFindsFirstElement() {
         let sut = SortedArray(sorted: 1..<10)
-        let index = sut.index(of: 1)
+        let index = sut.firstIndex(of: 1)
         XCTAssertEqual(index, 0)
     }
 
     func testIndexOfFindsLastElement() {
         let sut = SortedArray(sorted: 1..<10)
-        let index = sut.index(of: 9)
+        let index = sut.firstIndex(of: 9)
         XCTAssertEqual(index, 8)
     }
 
     func testIndexOfReturnsNilWhenNotFound() {
         let sut = SortedArray(unsorted: "Hello World")
-        let index = sut.index(of: "h")
+        let index = sut.firstIndex(of: "h")
         XCTAssertNil(index)
     }
 
     func testIndexOfReturnsNilForEmptyArray() {
         let sut = SortedArray<Int>()
-        let index = sut.index(of: 1)
+        let index = sut.firstIndex(of: 1)
         XCTAssertNil(index)
     }
 
     func testIndexOfCanDealWithSingleElementArray() {
         let sut = SortedArray<Int>(unsorted: [5])
-        let index = sut.index(of: 5)
+        let index = sut.firstIndex(of: 5)
         XCTAssertEqual(index, 0)
     }
 
     func testIndexOfFindsFirstIndexOfDuplicateElements1() {
         let sut = SortedArray(unsorted: [1,2,3,3,3,3,3,3,3,3,4,5])
-        let index = sut.index(of: 3)
+        let index = sut.firstIndex(of: 3)
         XCTAssertEqual(index, 2)
     }
 
     func testIndexOfFindsFirstIndexOfDuplicateElements2() {
         let sut = SortedArray(unsorted: [1,4,4,4,4,4,4,4,4,3,2])
-        let index = sut.index(of: 4)
+        let index = sut.firstIndex(of: 4)
         XCTAssertEqual(index, 3)
     }
 
     func testIndexOfFindsFirstIndexOfDuplicateElements3() {
         let sut = SortedArray(unsorted: String(repeating: "A", count: 10))
-        let index = sut.index(of: "A")
+        let index = sut.firstIndex(of: "A")
         XCTAssertEqual(index, 0)
     }
 
     func testIndexOfFindsFirstIndexOfDuplicateElements4() {
         let sut = SortedArray<Character>(unsorted: Array(repeating: "a", count: 100_000))
-        let index = sut.index(of: "a")
+        let index = sut.firstIndex(of: "a")
         XCTAssertEqual(index, 0)
     }
 
     func testIndexOfFindsFirstIndexOfDuplicateElements5() {
         let sourceArray = Array(repeating: 5, count: 100_000) + [1,2,6,7,8,9]
         let sut = SortedArray(unsorted: sourceArray)
-        let index = sut.index(of: 5)
+        let index = sut.firstIndex(of: 5)
+        XCTAssertEqual(index, 2)
+    }
+
+    func testIndexOfExistsAndIsAnAliasForFirstIndexOf() {
+        let sut = SortedArray(unsorted: [1,2,3,3,3,3,3,3,3,3,4,5])
+        let index = sut.index(of: 3)
         XCTAssertEqual(index, 2)
     }
 
@@ -369,6 +375,7 @@ extension SortedArrayTests {
             ("testIndexOfFindsFirstIndexOfDuplicateElements3", testIndexOfFindsFirstIndexOfDuplicateElements3),
             ("testIndexOfFindsFirstIndexOfDuplicateElements4", testIndexOfFindsFirstIndexOfDuplicateElements4),
             ("testIndexOfFindsFirstIndexOfDuplicateElements5", testIndexOfFindsFirstIndexOfDuplicateElements4),
+            ("testIndexOfExistsAndIsAnAliasForFirstIndexOf", testIndexOfExistsAndIsAnAliasForFirstIndexOf),
             ("testLastIndexOfFindsElementInMiddle", testLastIndexOfFindsElementInMiddle),
             ("testLastIndexOfFindsFirstElement", testLastIndexOfFindsFirstElement),
             ("testLastIndexOfFindsLastElement", testLastIndexOfFindsLastElement),