Remove swift-syntax/swift-format as generator dependencies (#343)

Remove swift-syntax/swift-format as generator dependencies

### Motivation

The swift-syntax/swift-format dependencies were only used to reformat the code before writing to disk, and significantly increased build and execution times, as well as leading to more dependency graph conflicts for our adopters. Turns out we can relatively easily remove the dependency, so doing that in this PR.

### Modifications

Removed swift-format/swift-syntax as dependencies and replaced them with an improved version of `TextBasedRenderer`, which now adds some basic indentation, surprisingly getting us pretty close to the previous formatting.

### Result

No more swift-syntax/swift-format dependency, but the generated code still looks very reasonable, and build/execution times should get noticably faster.

### Test Plan

Adapted unit tests, integration tests: snippet and file-based tests. All passing now.


Reviewed by: glbrntt

Builds:
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#343

Package.swift

@@ -52,18 +52,6 @@ let package = Package(
     ],
     dependencies: [
 
-        // Generate Swift code
-        .package(
-            url: "https://github.com/apple/swift-syntax.git",
-            "508.0.1"..<"510.0.0"
-        ),
-
-        // Format Swift code
-        .package(
-            url: "https://github.com/apple/swift-format.git",
-            "508.0.1"..<"510.0.0"
-        ),
-
         // General algorithms
         .package(
             url: "https://github.com/apple/swift-algorithms",
@@ -105,10 +93,6 @@ let package = Package(
                 .product(name: "OpenAPIKitCompat", package: "OpenAPIKit"),
                 .product(name: "Algorithms", package: "swift-algorithms"),
                 .product(name: "Yams", package: "Yams"),
-                .product(name: "SwiftSyntax", package: "swift-syntax"),
-                .product(name: "SwiftSyntaxBuilder", package: "swift-syntax"),
-                .product(name: "SwiftFormat", package: "swift-format"),
-                .product(name: "SwiftFormatConfiguration", package: "swift-format"),
             ],
             swiftSettings: swiftSettings
         ),
@@ -126,9 +110,7 @@ let package = Package(
         .testTarget(
             name: "OpenAPIGeneratorReferenceTests",
             dependencies: [
-                "_OpenAPIGeneratorCore",
-                .product(name: "SwiftFormat", package: "swift-format"),
-                .product(name: "SwiftFormatConfiguration", package: "swift-format"),
+                "_OpenAPIGeneratorCore"
             ],
             resources: [
                 .copy("Resources")

Sources/_OpenAPIGeneratorCore/Extensions/Foundation.swift

@@ -13,20 +13,6 @@
 //===----------------------------------------------------------------------===//
 import Foundation
 
-extension Data {
-    /// A copy of the data formatted using swift-format.
-    ///
-    /// Data is assumed to contain Swift code encoded using UTF-8.
-    ///
-    /// - Throws: When data is not valid UTF-8.
-    var swiftFormatted: Data {
-        get throws {
-            let string = String(decoding: self, as: UTF8.self)
-            return try Self(string.swiftFormatted.utf8)
-        }
-    }
-}
-
 extension InMemoryInputFile {
     /// Creates a new in-memory file by reading the contents at the specified path.
     /// - Parameter url: The path to the file to read.
@@ -36,17 +22,6 @@ extension InMemoryInputFile {
     }
 }
 
-extension InMemoryOutputFile {
-    /// A copy of the file formatted using swift-format.
-    public var swiftFormatted: InMemoryOutputFile {
-        get throws {
-            var new = self
-            new.contents = try contents.swiftFormatted
-            return new
-        }
-    }
-}
-
 /// File handle to stderr.
 let stdErrHandle = FileHandle.standardError
 

Sources/_OpenAPIGeneratorCore/GeneratorPipeline.swift

@@ -101,7 +101,6 @@ public func runGenerator(
 ///   - validator: A validator for parsed OpenAPI documents.
 ///   - translator: A translator from OpenAPI to Swift.
 ///   - renderer: A Swift code renderer.
-///   - formatter: A Swift code formatter.
 ///   - config: A set of configuration values for the generator.
 ///   - diagnostics: A collector to which the generator emits diagnostics.
 /// - Returns: A configured generator pipeline that can be executed with
@@ -110,8 +109,7 @@ func makeGeneratorPipeline(
     parser: any ParserProtocol = YamsParser(),
     validator: @escaping (ParsedOpenAPIRepresentation, Config) throws -> [Diagnostic] = validateDoc,
     translator: any TranslatorProtocol = MultiplexTranslator(),
-    renderer: any RendererProtocol = TextBasedRenderer(),
-    formatter: @escaping (InMemoryOutputFile) throws -> InMemoryOutputFile = { try $0.swiftFormatted },
+    renderer: any RendererProtocol = TextBasedRenderer.default,
     config: Config,
     diagnostics: any DiagnosticCollector
 ) -> GeneratorPipeline {
@@ -161,9 +159,7 @@ func makeGeneratorPipeline(
                     diagnostics: diagnostics
                 )
             },
-            postTransitionHooks: [
-                formatter
-            ]
+            postTransitionHooks: []
         )
     )
 }