Fix how we check if a range expression covers one value. (#815)

My previous fix, #806, had the wrong logic to determine if a confirmation's expected count as-a-`RangeExpression` had exactly one value, so we were printing sub-optimal messages on test failures. Specifically, this: ```swift await confirmation(expectedCount: 1) { // transformed to 1...1 // fail to confirm } ``` Would report "1...1 time(s)" instead of "1 time". ### Checklist: - [x] Code and documentation should follow the style of the [Style Guide](https://github.com/apple/swift-testing/blob/main/Documentation/StyleGuide.md). - [x] If public symbols are renamed or modified, DocC references should be updated.

Author: grynspan

Sources/Testing/Issues/Issue.swift

@@ -204,7 +204,7 @@ extension Issue.Kind: CustomStringConvertible {
  // bound." That's sufficient for us to determine if the range contains
  // a single value.
  let upperBound = expected.first { $0 > lowerBound }
- if let upperBound, upperBound > lowerBound && lowerBound == upperBound - 1 {
+ if upperBound == nil {
  return "Confirmation was confirmed \(actual.counting("time")), but expected to be confirmed \(lowerBound.counting("time"))"
  }
  }

Tests/TestingTests/ConfirmationTests.swift

@@ -51,12 +51,36 @@ struct ConfirmationTests {
  var configuration = Configuration()
  configuration.eventHandler = { event, _ in
  if case let .issueRecorded(issue) = event.kind {
- #expect(String(describing: issue) != "")
+ #expect(String(describing: issue).contains("time(s)"))
  }
  }
 
  await Test {
  await confirmation(expectedCount: 1...) { _ in }
+ await confirmation(expectedCount: 1...2) { _ in }
+ await confirmation(expectedCount: 1..<3) { _ in }
+ }.run(configuration: configuration)
+ }
+
+ @Test func confirmationFailureCanBeDescribedAsSingleValue() async {
+ var configuration = Configuration()
+ configuration.eventHandler = { event, _ in
+ if case let .issueRecorded(issue) = event.kind {
+ #expect(!String(describing: issue).contains("time(s)"))
+ }
+ }
+
+ await Test {
+ await confirmation(expectedCount: 1...1) { _ in }
+ await confirmation(expectedCount: 1..<2) { _ in }
+ await confirmation(expectedCount: Int.max...Int.max) { _ in }
+#if !SWT_NO_EXIT_TESTS
+ await withKnownIssue("Crashes in Swift standard library (rdar://139568287)") {
+ await #expect(exitsWith: .success) {
+ await confirmation(expectedCount: Int.max...) { _ in }
+ }
+ }
+#endif
  }.run(configuration: configuration)
  }