add PluginExample for UseAccessLevelOnImports option

PluginExamples/Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version: 5.6
+// swift-tools-version: 5.8
 
 import PackageDescription
 
@@ -14,6 +14,7 @@ let package = Package(
                 .target(name: "Simple"),
                 .target(name: "Nested"),
                 .target(name: "Import"),
+                .target(name: "AccessLevelOnImport"),
             ]
         ),
         .target(
@@ -43,5 +44,17 @@ let package = Package(
                 .plugin(name: "SwiftProtobufPlugin", package: "swift-protobuf")
             ]
         ),
+        .target(
+            name: "AccessLevelOnImport",
+            dependencies: [
+                .product(name: "SwiftProtobuf", package: "swift-protobuf"),
+            ],
+            swiftSettings: [
+                .enableExperimentalFeature("AccessLevelOnImport"),
+            ],
+            plugins: [
+                .plugin(name: "SwiftProtobufPlugin", package: "swift-protobuf")
+            ]
+        )
     ]
 )

PluginExamples/Sources/AccessLevelOnImport/AccessLevelOnImport/AccessLevelOnImport.proto

@@ -0,0 +1,7 @@
+syntax = "proto3";
+
+import "Dependency/Dependency.proto";
+
+message AccessLevelOnImport {
+  Dependency dependency = 1;
+}

PluginExamples/Sources/AccessLevelOnImport/Dependency/Dependency.proto

@@ -0,0 +1,5 @@
+syntax = "proto3";
+
+message Dependency {
+  string name = 1;
+}

PluginExamples/Sources/AccessLevelOnImport/empty.swift

@@ -0,0 +1,3 @@
+/// DO NOT DELETE.
+///
+/// We need to keep this file otherwise the plugin is not running.

PluginExamples/Sources/AccessLevelOnImport/swift-protobuf-config.json

@@ -0,0 +1,12 @@
+{
+    "invocations": [
+        {
+            "protoFiles": [
+                "AccessLevelOnImport/AccessLevelOnImport.proto",
+                "Dependency/Dependency.proto",
+            ],
+            "visibility": "public",
+            "useAccessLevelOnImports": true
+        }
+    ]
+}

PluginExamples/Sources/ExampleTests/ExampleTests.swift

@@ -1,6 +1,7 @@
 import Simple
 import Nested
 import Import
+import AccessLevelOnImport
 
 import XCTest
 
@@ -19,4 +20,13 @@ final class ExampleTests: XCTestCase {
         let foo = Foo.with { $0.bar = .with { $0.name = "Bar" } }
         XCTAssertEqual(foo.bar.name, "Bar")
     }
+
+#if compiler(>=5.9)
+    #if hasFeature(AccessLevelOnImport)
+    func testAccessLevelOnImport() {
+        let foo = Foo.with { $0.bar = .with { $0.name = "Bar" } }
+        XCTAssertEqual(foo.bar.name, "Bar")
+    }
+    #endif
+#endif
 }