Update XCSharedData Writable conformance to include WorkspaceSettings (…

…#743)

Resolves #738

### Short description 📝
- Update `XCSharedData` `Writable` conformance so that `WorkspaceSettings` are written.

### Solution 📦

- There was already a pattern defined for writing `XCSharedData` properties (`schemes` and `breakpoints`), and so I followed the same pattern to write the `workspaceSettings` property.

Sources/XcodeProj/Project/WorkspaceSettings.swift

@@ -153,3 +153,9 @@ public class WorkspaceSettings: Codable, Equatable, Writable {
         try path.write(data)
     }
 }
+
+extension WorkspaceSettings {
+    static func path(_ path: Path) -> Path {
+        path + "WorkspaceSettings.xcsettings"
+    }
+}

Sources/XcodeProj/Project/XCSharedData.swift

@@ -63,6 +63,7 @@ public final class XCSharedData: Equatable, Writable {
     public func write(path: Path, override: Bool) throws {
         try writeSchemes(path: path, override: override)
         try writeBreakpoints(path: path, override: override)
+        try writeWorkspaceSettings(path: path, override: override)
     }
 
     func writeSchemes(path: Path, override: Bool) throws {
@@ -91,6 +92,20 @@ public final class XCSharedData: Equatable, Writable {
         try debuggerPath.mkpath()
         try breakpoints.write(path: XCBreakpointList.path(debuggerPath), override: override)
     }
+
+    func writeWorkspaceSettings(path: Path, override: Bool) throws {
+        /**
+         * We don't want to delete this path when `override` is `true` because
+         * that will delete everything in the folder, including schemes and breakpoints.
+         * Instead, just create the path if it doesn't exist and let the `write` method
+         * in `WorkspaceSettings` handle the override.
+         */
+        if !path.exists {
+            try path.mkpath()
+        }
+
+        try workspaceSettings?.write(path: WorkspaceSettings.path(path), override: override)
+    }
 }
 
 extension XCSharedData {

Tests/XcodeProjTests/Project/XcodeProjTests.swift

@@ -24,6 +24,25 @@ final class XcodeProjIntegrationTests: XCTestCase {
         try testReadWriteProducesNoDiff(from: iosProjectPath,
                                         initModel: XcodeProj.init(path:))
     }
+
+    func test_write_includes_workspace_settings() throws {
+        // Define workspace settings that should be written
+        let workspaceSettings = WorkspaceSettings(buildSystem: .new, derivedDataLocationStyle: .default, autoCreateSchemes: false)
+
+        testWrite(from: iosProjectPath,
+                  initModel: { try? XcodeProj(path: $0) },
+                  modify: { project in
+                      project.sharedData?.workspaceSettings = workspaceSettings
+                      return project
+                  },
+                  assertion: {
+                      /**
+                       * Expect that the workspace settings read from file are equal to the
+                       * workspace settings we expected to write.
+                       */
+                      XCTAssertEqual($1.sharedData?.workspaceSettings, workspaceSettings)
+                  })
+    }
 
     // MARK: - Private