Relax minimum platforms to macOS 10.15, iOS 13, tvOS 13, and watchOS 6 (#18)

### Motivation

Reduce deployment target by 3 versions to gain more adoption.

### Modifications

- Reduced deployment targets by 3 versions
- Modified `Converter#renderedRequestPath` to support iOS 13

### Result

Deployment target will be reduced by 3 versions.

### Related issues

- Related to apple/swift-openapi-generator#62

### Related PRs

- Paired with apple/swift-openapi-generator#63

---------

Co-authored-by: andrewelliott <>
Co-authored-by: Honza Dvorsky <[email protected]>

Author: andrewse02

Package.swift

@@ -17,7 +17,7 @@ import PackageDescription
 let package = Package(
     name: "swift-openapi-runtime",
     platforms: [
-        .macOS(.v13), .iOS(.v16), .tvOS(.v16), .watchOS(.v9),
+        .macOS(.v10_15), .iOS(.v13), .tvOS(.v13), .watchOS(.v6),
     ],
     products: [
         .library(

Sources/OpenAPIRuntime/Conversion/Converter+Client.swift

@@ -22,11 +22,13 @@ extension Converter {
     ) throws -> String {
         var renderedString = template
         for parameter in parameters {
-            renderedString.replace(
-                "{}",
-                with: parameter.description,
-                maxReplacements: 1
-            )
+            if let range = renderedString.range(of: "{}") {
+                renderedString = renderedString.replacingOccurrences(
+                    of: "{}",
+                    with: parameter.description,
+                    range: range
+                )
+            }
         }
         return renderedString
     }