[test] update bridged string tests

- move to a new file
- create a new `NSString` object for each new test

Author: glessard

test/stdlib/Span/BridgedStringUTF8ViewSpanTests.swift

@@ -0,0 +1,97 @@
+//===--- BridgedStringSpanTests.swift -------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2025 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+// RUN: %target-run-stdlib-swift -enable-experimental-feature LifetimeDependence
+
+// REQUIRES: executable_test
+// REQUIRES: objc_interop
+// REQUIRES: swift_feature_LifetimeDependence
+
+import StdlibUnittest
+
+import Foundation
+
+var suite = TestSuite("EagerLazyBridging String Tests")
+defer { runAllTests() }
+
+let strings = [
+  "Hello, World!",
+  "A long ASCII string exceeding 16 code units.",
+  "🇯🇵",
+  "🏂☃❅❆❄︎⛄️❄️",
+]
+
+strings.forEach { expected in
+  suite.test("Span from Bridged String Stability: \(expected)")
+  .require(.stdlib_6_2).code {
+    guard #available(SwiftStdlib 6.2, *) else { return }
+
+    let string = NSString(utf8String: expected)
+    expectNotNil(string)
+    guard let string = NSString(utf8String: expected) else { return }
+
+    let bridged = String(string).utf8
+    var p: ObjectIdentifier? = nil
+    for (i, j) in zip(0..<3, bridged.indices) {
+      let span = bridged.span
+      let c = span.withUnsafeBufferPointer {
+        let o = unsafeBitCast($0.baseAddress, to: ObjectIdentifier.self)
+        if p == nil {
+          p = o
+        } else {
+          expectEqual(p, o)
+        }
+        return $0[i]
+      }
+      expectEqual(c, bridged[j])
+    }
+  }
+}
+
+strings.forEach { expected in
+  suite.test("Span from Bridged String: \(expected)")
+  .require(.stdlib_6_2).code {
+    guard #available(SwiftStdlib 6.2, *) else { return }
+
+    let string = NSString(utf8String: expected)
+    expectNotNil(string)
+    guard let string = NSString(utf8String: expected) else { return }
+
+    let bridged = String(string)
+    let utf8 = bridged.utf8
+    let span = utf8.span
+    expectEqual(span.count, expected.utf8.count)
+    for (i,j) in zip(span.indices, expected.utf8.indices) {
+      expectEqual(span[i], expected.utf8[j])
+    }
+  }
+}
+
+strings.forEach { expected in
+  suite.test("Span from Bridged String Substring: \(expected)")
+  .require(.stdlib_6_2).code {
+    guard #available(SwiftStdlib 6.2, *) else { return }
+
+    let string = NSString(utf8String: expected)
+    expectNotNil(string)
+    guard let string = NSString(utf8String: expected) else { return }
+
+    let bridged = String(string).dropFirst()
+    let utf8 = bridged.utf8
+    let span = utf8.span
+    let expected = expected.dropFirst()
+    expectEqual(span.count, expected.utf8.count)
+    for (i,j) in zip(span.indices, expected.utf8.indices) {
+      expectEqual(span[i], expected.utf8[j])
+    }
+  }
+}

test/stdlib/Span/StringUTF8SpanProperty.swift

@@ -85,43 +85,3 @@ suite.test("Span from Large Native String's Substring")
     expectEqual(span[i], u[i])
   }
 }
-
-import Foundation
-
-let strings: [NSString: String] = [
-  "Hello, World!" as NSString: "Hello, World!",
-  "A long ASCII string exceeding 16 code units." as NSString: "A long ASCII string exceeding 16 code units.",
-  "🇯🇵" as NSString: "🇯🇵",
-  NSString(utf8String: "🏂☃❅❆❄︎⛄️❄️")!: "🏂☃❅❆❄︎⛄️❄️",
-]
-
-strings.forEach { string, expected in
-  suite.test("Span from Bridged String: \(expected)")
-  .require(.stdlib_6_2).code {
-    guard #available(SwiftStdlib 6.2, *) else { return }
-
-    let bridged = String(string)
-    let utf8 = bridged.utf8
-    let span = utf8.span
-    expectEqual(span.count, expected.utf8.count)
-    for (i,j) in zip(span.indices, expected.utf8.indices) {
-      expectEqual(span[i], expected.utf8[j])
-    }
-  }
-}
-
-strings.forEach { string, expected in
-  suite.test("Span from Bridged String Substring: \(expected)")
-  .require(.stdlib_6_2).code {
-    guard #available(SwiftStdlib 6.2, *) else { return }
-
-    let bridged = String(string).dropFirst()
-    let utf8 = bridged.utf8
-    let span = utf8.span
-    let expected = expected.dropFirst()
-    expectEqual(span.count, expected.utf8.count)
-    for (i,j) in zip(span.indices, expected.utf8.indices) {
-      expectEqual(span[i], expected.utf8[j])
-    }
-  }
-}