Unit test wrapping adjacent pairs collection

apple · May 7, 2021 · 98a5278 · 98a5278
1 parent 8d96786
commit 98a5278
Showing 1 changed file with 41 additions and 0 deletions.
diff --git a/Tests/SwiftAlgorithmsTests/AdjacentPairsTests.swift b/Tests/SwiftAlgorithmsTests/AdjacentPairsTests.swift
@@ -73,29 +73,57 @@ final class AdjacentPairsTests: XCTestCase {
     XCTAssertEqualSequences(pairs, [], by: ==)
   }
 
+  func testZeroElementsWrapping() {
+    let pairs = (0..<0).adjacentPairs(wrapping: true)
+    XCTAssertEqual(pairs.startIndex, pairs.endIndex)
+    XCTAssertEqualSequences(pairs, [], by: ==)
+  }
+
   func testOneElement() {
     let pairs = (0..<1).adjacentPairs()
     XCTAssertEqual(pairs.startIndex, pairs.endIndex)
     XCTAssertEqualSequences(pairs, [], by: ==)
   }
 
+  func testOneElementWrapping() {
+    let pairs = (0..<1).adjacentPairs(wrapping: true)
+    XCTAssertEqualSequences(pairs, [(0, 0)], by: ==)
+  }
+
   func testTwoElements() {
     let pairs = (0..<2).adjacentPairs()
     XCTAssertEqualSequences(pairs, [(0, 1)], by: ==)
   }
 
+  func testTwoElementsWrapping() {
+    let pairs = (0..<2).adjacentPairs(wrapping: true)
+    XCTAssertEqualSequences(pairs, [(0, 1), (1, 0)], by: ==)
+  }
+
   func testThreeElements() {
     let pairs = (0..<3).adjacentPairs()
     XCTAssertEqualSequences(pairs, [(0, 1), (1, 2)], by: ==)
   }
 
+  func testThreeElementsWrapping() {
+    let pairs = (0..<3).adjacentPairs(wrapping: true)
+    XCTAssertEqualSequences(pairs, [(0, 1), (1, 2), (2, 0)], by: ==)
+  }
+
   func testManyElements() {
     for n in 4...100 {
       let pairs = (0..<n).adjacentPairs()
       XCTAssertEqualSequences(pairs, zip(0..., 1...).prefix(n - 1), by: ==)
     }
   }
 
+  func testManyElementsWrapping() {
+    for n in 4...100 {
+      let pairs = (0..<n).adjacentPairs(wrapping: true)
+      XCTAssertEqualSequences(pairs, chain(zip(0..., 1...).prefix(n - 1), [((n - 1), 0)]), by: ==)
+    }
+  }
+
   func testIndexTraversals() {
     validateIndexTraversals(
       (0..<0).adjacentPairs(),
@@ -104,8 +132,21 @@ final class AdjacentPairsTests: XCTestCase {
       (0..<5).adjacentPairs())
   }
 
+  func testIndexTraversalsWrapping() {
+    validateIndexTraversals(
+      (0..<0).adjacentPairs(wrapping: true),
+      (0..<1).adjacentPairs(wrapping: true),
+      (0..<2).adjacentPairs(wrapping: true),
+      (0..<5).adjacentPairs(wrapping: true))
+  }
+
   func testLaziness() {
     XCTAssertLazySequence((0...).lazy.adjacentPairs())
     XCTAssertLazyCollection((0..<100).lazy.adjacentPairs())
   }
+
+  func testLazinessWrapping() {
+    XCTAssertLazySequence((0...).lazy.adjacentPairs(wrapping: true))
+    XCTAssertLazyCollection((0..<100).lazy.adjacentPairs(wrapping: true))
+  }
 }