Add some new swift-format 5.9 rules (#356)

Add some new swift-format 5.9 rules

### Motivation

I scanned the swift-format 5.9 release notes and found a few new rules that can make our code further consistent.

### Modifications

Added those rules and reformatted.

The only hand-made change is in `.swift-format`, the rest is the result of rerunning swift-format.

### Result

More consistent code, fewer style discussions on PRs.

### Test Plan

CI.


Reviewed by: simonjbeaumont

Builds:
     ✔︎ pull request validation (5.10) - Build finished. 
     ✔︎ pull request validation (5.8) - Build finished. 
     ✔︎ pull request validation (5.9) - Build finished. 
     ✔︎ pull request validation (compatibility test) - Build finished. 
     ✔︎ pull request validation (docc test) - Build finished. 
     ✔︎ pull request validation (integration test) - Build finished. 
     ✔︎ pull request validation (nightly) - Build finished. 
     ✔︎ pull request validation (soundness) - Build finished. 

#356

.swift-format

@@ -18,6 +18,7 @@
   "rules" : {
     "AllPublicDeclarationsHaveDocumentation" : true,
     "AlwaysUseLowerCamelCase" : false,
+    "AlwaysUseLiteralForEmptyCollectionInit" : true,
     "AmbiguousTrailingClosureOverload" : true,
     "BeginDocumentationCommentWithOneLineSummary" : false,
     "DoNotUseSemicolons" : true,
@@ -38,10 +39,12 @@
     "NoLeadingUnderscores" : false,
     "NoParensAroundConditions" : true,
     "NoVoidReturnOnFunctionSignature" : true,
+    "OmitExplicitReturns" : true,
     "OneCasePerLine" : true,
     "OneVariableDeclarationPerLine" : true,
     "OnlyOneTrailingClosureArgument" : true,
     "OrderedImports" : false,
+    "ReplaceForEachWithForLoop" : true,
     "ReturnVoidInsteadOfEmptyTuple" : true,
     "UseEarlyExits" : false,
     "UseLetInEveryBoundCaseVariable" : false,

Plugins/OpenAPIGenerator/plugin.swift

@@ -62,7 +62,7 @@ import XcodeProjectPlugin
 
 extension SwiftOpenAPIGeneratorPlugin: XcodeBuildToolPlugin {
     func createBuildCommands(context: XcodePluginContext, target: XcodeTarget) throws -> [Command] {
-        return try createBuildCommands(
+        try createBuildCommands(
             pluginWorkDirectory: context.pluginWorkDirectory,
             tool: context.tool,
             sourceFiles: target.inputFiles,

Sources/_OpenAPIGeneratorCore/Layers/StructuredSwiftRepresentation.swift

@@ -1251,7 +1251,7 @@ extension Declaration {
 
 extension FunctionKind {
     /// Returns a non-failable initializer, for example `init()`.
-    static var initializer: Self { return .initializer(failable: false) }
+    static var initializer: Self { .initializer(failable: false) }
 
     /// Returns a non-static function kind.
     static func function(name: String) -> Self { .function(name: name, isStatic: false) }
@@ -1262,12 +1262,12 @@ extension CodeBlock {
     /// Returns a new declaration code block wrapping the provided declaration.
     /// - Parameter declaration: The declaration to wrap.
     /// - Returns: A new `CodeBlock` instance containing the provided declaration.
-    static func declaration(_ declaration: Declaration) -> Self { return CodeBlock(item: .declaration(declaration)) }
+    static func declaration(_ declaration: Declaration) -> Self { CodeBlock(item: .declaration(declaration)) }
 
     /// Returns a new expression code block wrapping the provided expression.
     /// - Parameter expression: The expression to wrap.
     /// - Returns: A new `CodeBlock` instance containing the provided declaration.
-    static func expression(_ expression: Expression) -> Self { return CodeBlock(item: .expression(expression)) }
+    static func expression(_ expression: Expression) -> Self { CodeBlock(item: .expression(expression)) }
 }
 
 extension Expression {
@@ -1290,7 +1290,7 @@ extension Expression {
     /// expression.
     /// - Parameter member: The name of the member to access on the expression.
     /// - Returns: A new expression representing member access.
-    func dot(_ member: String) -> Expression { return .memberAccess(.init(left: self, right: member)) }
+    func dot(_ member: String) -> Expression { .memberAccess(.init(left: self, right: member)) }
 
     /// Returns a new expression that calls the current expression as a function
     /// with the specified arguments.
@@ -1306,7 +1306,7 @@ extension Expression {
     /// For example: `.foo`, where `member` is `foo`.
     /// - Parameter member: The name of the member to access.
     /// - Returns: A new expression representing member access with a dot prefix.
-    static func dot(_ member: String) -> Self { return Self.memberAccess(.init(right: member)) }
+    static func dot(_ member: String) -> Self { Self.memberAccess(.init(right: member)) }
 
     /// Returns a new identifier expression for the provided pattern, such
     /// as a variable or function name.

Sources/_OpenAPIGeneratorCore/Parser/YamsParser.swift

@@ -27,7 +27,7 @@ public struct YamsParser: ParserProtocol {
     /// - Returns: An array of top-level keys as strings.
     /// - Throws: An error if there are any issues with parsing the YAML string.
     public static func extractTopLevelKeys(fromYAMLString yamlString: String) throws -> [String] {
-        var yamlKeys = [String]()
+        var yamlKeys: [String] = []
         let parser = try Parser(yaml: yamlString)
 
         if let rootNode = try parser.singleRoot(), case let .mapping(mapping) = rootNode {
@@ -126,7 +126,7 @@ extension Diagnostic {
     ///   - location: Describes the input file being worked on when the error occurred.
     /// - Returns: An error diagnostic.
     static func openAPIVersionError(versionString: String, location: Location) -> Diagnostic {
-        return error(
+        error(
             message:
                 "Unsupported document version: \(versionString). Please provide a document with OpenAPI versions in the 3.0.x or 3.1.x sets.",
             location: location
@@ -137,7 +137,7 @@ extension Diagnostic {
     /// - Parameter location: Describes the input file being worked on when the error occurred
     /// - Returns: An error diagnostic.
     static func openAPIMissingVersionError(location: Location) -> Diagnostic {
-        return error(
+        error(
             message:
                 "No openapi key found, please provide a valid OpenAPI document with OpenAPI versions in the 3.0.x or 3.1.x sets.",
             location: location

Sources/_OpenAPIGeneratorCore/Translator/Operations/OperationDescription.swift

@@ -102,7 +102,7 @@ extension OperationDescription {
 
     /// Returns the type name of the namespace unique to the operation.
     var operationNamespace: TypeName {
-        return .init(
+        .init(
             components: [.root, .init(swift: Constants.Operations.namespace, json: "paths")]
                 + path.components.map { .init(swift: nil, json: $0) } + [
                     .init(swift: methodName, json: httpMethod.rawValue)

Sources/_OpenAPIGeneratorCore/Translator/Responses/translateResponseHeader.swift

@@ -126,7 +126,7 @@ extension ServerFileTranslator {
     func translateResponseHeaderInServer(_ header: TypedResponseHeader, responseVariableName: String) throws
         -> Expression
     {
-        return .try(
+        .try(
             .identifierPattern("converter").dot("setHeaderFieldAs\(header.codingStrategy.runtimeName)")
                 .call([
                     .init(

Sources/swift-openapi-generator/GenerateOptions.swift

@@ -98,7 +98,7 @@ extension _GenerateOptions {
         do {
             let data = try Data(contentsOf: config)
             let configAsString = String(decoding: data, as: UTF8.self)
-            var yamlKeys = [String]()
+            var yamlKeys: [String] = []
 
             do { yamlKeys = try YamsParser.extractTopLevelKeys(fromYAMLString: configAsString) } catch {
                 throw ValidationError("The config isn't valid. \(error)")

Tests/PetstoreConsumerTests/Test_Client.swift

@@ -676,7 +676,7 @@ final class Test_Client: XCTestCase {
 
     func testUploadAvatarForPet_500() async throws {
         transport = .init { request, requestBody, baseURL, operationID in
-            return try HTTPResponse(status: .internalServerError, headerFields: [.contentType: "text/plain"])
+            try HTTPResponse(status: .internalServerError, headerFields: [.contentType: "text/plain"])
                 .withEncodedBody(Data.efghString)
         }
         let response = try await client.uploadAvatarForPet(.init(path: .init(petId: 1), body: .binary(.init(.abcd))))

Tests/PetstoreConsumerTests/Test_Server.swift

@@ -79,7 +79,7 @@ final class Test_Server: XCTestCase {
 
     func testListPets_default() async throws {
         client = .init(listPetsBlock: { input in
-            return .default(statusCode: 400, .init(body: .json(.init(code: 1, me_dollar_sage: "Oh no!"))))
+            .default(statusCode: 400, .init(body: .json(.init(code: 1, me_dollar_sage: "Oh no!"))))
         })
         let (response, responseBody) = try await server.listPets(
             .init(soar_path: "/api/pets", method: .get),
@@ -377,7 +377,7 @@ final class Test_Server: XCTestCase {
     }
 
     func testGetStats_200_json() async throws {
-        client = .init(getStatsBlock: { input in return .ok(.init(body: .json(.init(count: 1)))) })
+        client = .init(getStatsBlock: { input in .ok(.init(body: .json(.init(count: 1)))) })
         let (response, responseBody) = try await server.getStats(
             .init(
                 soar_path: "/api/pets/stats",
@@ -400,7 +400,7 @@ final class Test_Server: XCTestCase {
     }
 
     func testGetStats_200_unexpectedAccept() async throws {
-        client = .init(getStatsBlock: { input in return .ok(.init(body: .json(.init(count: 1)))) })
+        client = .init(getStatsBlock: { input in .ok(.init(body: .json(.init(count: 1)))) })
         do {
             _ = try await server.getStats(
                 .init(soar_path: "/api/pets/stats", method: .patch, headerFields: [.accept: "foo/bar"]),
@@ -412,7 +412,7 @@ final class Test_Server: XCTestCase {
     }
 
     func testGetStats_200_text() async throws {
-        client = .init(getStatsBlock: { input in return .ok(.init(body: .plainText("count is 1"))) })
+        client = .init(getStatsBlock: { input in .ok(.init(body: .plainText("count is 1"))) })
         let (response, responseBody) = try await server.getStats(
             .init(
                 soar_path: "/api/pets/stats",
@@ -521,7 +521,7 @@ final class Test_Server: XCTestCase {
     }
 
     func testGetStats_200_binary() async throws {
-        client = .init(getStatsBlock: { input in return .ok(.init(body: .binary("count_is_1"))) })
+        client = .init(getStatsBlock: { input in .ok(.init(body: .binary("count_is_1"))) })
         let (response, responseBody) = try await server.getStats(
             .init(
                 soar_path: "/api/pets/stats",
@@ -634,7 +634,7 @@ final class Test_Server: XCTestCase {
     }
 
     func testProbe_204() async throws {
-        client = .init(probeBlock: { input in return .noContent(.init()) })
+        client = .init(probeBlock: { input in .noContent(.init()) })
         let (response, responseBody) = try await server.probe(
             .init(soar_path: "/api/probe/", method: .post),
             nil,