Lower Apple Platform requirement in Package.swift (#102)

* Lower Apple Platform requirement in Package.swift

* Update TemporaryGettingStarted.md to match version

Author: Kyle-Ye

Package.swift

@@ -17,10 +17,11 @@ let package = Package(
   name: "swift-testing",
 
   platforms: [
-    .macOS(.v13),
-    .iOS(.v16),
-    .watchOS(.v9),
-    .tvOS(.v16),
+    .macOS(.v10_15),
+    .iOS(.v13),
+    .watchOS(.v6),
+    .tvOS(.v13),
+    .macCatalyst(.v13),
     .visionOS(.v1),
   ],
 

Sources/GitStatus/main.swift

@@ -56,10 +56,17 @@ func _runGit(passing arguments: String..., readingUpToCount maxOutputCount: Int)
   defer {
     process.terminate()
   }
-  guard let output = try? stdoutPipe.fileHandleForReading.read(upToCount: maxOutputCount) else {
-    return nil
+  if #available(macOS 10.15.4, *) {
+    guard let output = try? stdoutPipe.fileHandleForReading.read(upToCount: maxOutputCount) else {
+      return nil
+    }
+    return String(data: output, encoding: .utf8)
+  } else {
+    guard let output = try? stdoutPipe.fileHandleForReading.readData(ofLength: maxOutputCount) else {
+      return nil
+    }
+    return String(data: output, encoding: .utf8)
   }
-  return String(data: output, encoding: .utf8)
 #else
   return nil
 #endif

Sources/Testing/Testing.docc/TemporaryGettingStarted.md

@@ -65,7 +65,7 @@ can be used with):
 
 ```swift
 platforms: [
-  .macOS(.v13), .iOS(.v16), .watchOS(.v9), .tvOS(.v16), .visionOS(.v1)
+  .macOS(.v10_15), .iOS(.v13), .watchOS(.v6), .tvOS(.v13), .macCatalyst(.v13), .visionOS(.v1)
 ],
 ```