fix(csharp): handle referencing System when a type named System exi…

…sts (#6005)

.github/actions/cached-seed/action.yaml

@@ -62,7 +62,7 @@ runs:
     - name: Install protoc-gen-openapi
       if: steps.cache.outputs.cache-hit != 'true'
       shell: bash
-      run: go install github.com/google/gnostic/cmd/protoc-gen-openapi@v0.7.0
+      run: go install github.com/fern-api/protoc-gen-openapi/cmd/protoc-gen-openapi@latest
 
     - name: Seed Test
       if: steps.cache.outputs.cache-hit != 'true'

generators/csharp/codegen/src/asIs/CollectionItemSerializer.cs

@@ -23,7 +23,7 @@ internal class CollectionItemSerializer<TDatatype, TConverterType>
     /// <returns>Created object.</returns>
     public override IEnumerable<TDatatype>? Read(
         ref Utf8JsonReader reader,
-        System.Type typeToConvert,
+        global::System.Type typeToConvert,
         JsonSerializerOptions options
     )
     {

generators/csharp/codegen/src/asIs/DateTimeSerializer.cs

@@ -8,7 +8,7 @@ internal class DateTimeSerializer : JsonConverter<DateTime>
 {
     public override DateTime Read(
         ref Utf8JsonReader reader,
-        System.Type typeToConvert,
+        global::System.Type typeToConvert,
         JsonSerializerOptions options
     )
     {

generators/csharp/codegen/src/asIs/EnumSerializer.Template.cs

@@ -5,7 +5,7 @@
 namespace <%= namespace%>;
 
 internal class EnumSerializer<TEnum> : JsonConverter<TEnum>
-    where TEnum : struct, System.Enum
+    where TEnum : struct, Enum
 {
     private readonly Dictionary<TEnum, string> _enumToString = new();
     private readonly Dictionary<string, TEnum> _stringToEnum = new();
@@ -36,7 +36,7 @@ public EnumSerializer()
 
     public override TEnum Read(
         ref Utf8JsonReader reader,
-        System.Type typeToConvert,
+        global::System.Type typeToConvert,
         JsonSerializerOptions options
     )
     {

generators/csharp/codegen/src/asIs/OneOfSerializer.cs

@@ -9,7 +9,7 @@ internal class OneOfSerializer : JsonConverter<IOneOf>
 {
     public override IOneOf? Read(
         ref Utf8JsonReader reader,
-        System.Type typeToConvert,
+        global::System.Type typeToConvert,
         JsonSerializerOptions options
     )
     {
@@ -38,7 +38,7 @@ public override void Write(Utf8JsonWriter writer, IOneOf value, JsonSerializerOp
         JsonSerializer.Serialize(writer, value.Value, options);
     }
 
-    private static (System.Type type, MethodInfo cast)[] GetOneOfTypes(System.Type typeToConvert)
+    private static (global::System.Type type, MethodInfo cast)[] GetOneOfTypes(global::System.Type typeToConvert)
     {
         var type = typeToConvert;
         if (Nullable.GetUnderlyingType(type) is { } underlyingType)

generators/csharp/sdk/versions.yml

@@ -7,6 +7,15 @@
 #         Set `enable-forward-compatible-enums` to `false` in the configuration to generate the old enums.
 #   irVersion: 53
 
+- version: 1.9.25
+  createdAt: "2025-02-14"
+  irVersion: 53
+  changelogEntry:
+    - type: fix
+      summary: |
+        Use `global::System.Type` instead of `System.Type` in generated code to avoid potential naming conflicts 
+        when a type named `System` exists in the current namespace.
+
 - version: 1.9.24
   createdAt: "2025-02-14"
   irVersion: 53

packages/seed/src/commands/test/test-runner/TestRunner.ts

@@ -108,61 +108,61 @@ export abstract class TestRunner {
      * Runs the generator.
      */
     public async run({ fixture, configuration }: TestRunner.RunArgs): Promise<TestRunner.TestResult> {
-        if (this.buildInvocation == null) {
-            this.buildInvocation = this.build();
-        }
-        await this.buildInvocation;
+        try {
+            if (this.buildInvocation == null) {
+                this.buildInvocation = this.build();
+            }
+            await this.buildInvocation;
 
-        const metrics: TestRunner.TestCaseMetrics = {};
+            const metrics: TestRunner.TestCaseMetrics = {};
 
-        const id = configuration != null ? `${fixture}:${configuration.outputFolder}` : `${fixture}`;
-        const absolutePathToAPIDefinition = AbsoluteFilePath.of(
-            path.join(__dirname, FERN_DIRECTORY, APIS_DIRECTORY, fixture)
-        );
-        const taskContext = this.taskContextFactory.create(`${this.generator.workspaceName}:${id}`);
-        const outputFolder = configuration?.outputFolder ?? fixture;
-        const outputDir =
-            configuration == null
-                ? join(this.generator.absolutePathToWorkspace, RelativeFilePath.of(fixture))
-                : join(
-                      this.generator.absolutePathToWorkspace,
-                      RelativeFilePath.of(fixture),
-                      RelativeFilePath.of(configuration.outputFolder)
-                  );
-        const language = this.generator.workspaceConfig.language;
-        const outputVersion = configuration?.outputVersion ?? "0.0.1";
-        const customConfig =
-            this.generator.workspaceConfig.defaultCustomConfig != null || configuration?.customConfig != null
-                ? {
-                      ...(this.generator.workspaceConfig.defaultCustomConfig ?? {}),
-                      ...((configuration?.customConfig as Record<string, unknown>) ?? {})
-                  }
-                : undefined;
-        const publishConfig = configuration?.publishConfig;
-        const outputMode = configuration?.outputMode ?? this.generator.workspaceConfig.defaultOutputMode;
-        const irVersion = this.generator.workspaceConfig.irVersion;
-        const publishMetadata = configuration?.publishMetadata ?? undefined;
-        const readme = configuration?.readmeConfig ?? undefined;
-        const fernWorkspace = await (
-            await convertGeneratorWorkspaceToFernWorkspace({
-                absolutePathToAPIDefinition,
-                taskContext,
-                fixture
-            })
-        )?.toFernWorkspace({ context: taskContext });
-        if (fernWorkspace == null) {
-            return {
-                type: "failure",
-                cause: "invalid-fixture",
-                message: `Failed to validate fixture ${fixture}`,
-                id: fixture,
-                outputFolder,
-                metrics
-            };
-        }
+            const id = configuration != null ? `${fixture}:${configuration.outputFolder}` : `${fixture}`;
+            const absolutePathToAPIDefinition = AbsoluteFilePath.of(
+                path.join(__dirname, FERN_DIRECTORY, APIS_DIRECTORY, fixture)
+            );
+            const taskContext = this.taskContextFactory.create(`${this.generator.workspaceName}:${id}`);
+            const outputFolder = configuration?.outputFolder ?? fixture;
+            const outputDir =
+                configuration == null
+                    ? join(this.generator.absolutePathToWorkspace, RelativeFilePath.of(fixture))
+                    : join(
+                          this.generator.absolutePathToWorkspace,
+                          RelativeFilePath.of(fixture),
+                          RelativeFilePath.of(configuration.outputFolder)
+                      );
+            const language = this.generator.workspaceConfig.language;
+            const outputVersion = configuration?.outputVersion ?? "0.0.1";
+            const customConfig =
+                this.generator.workspaceConfig.defaultCustomConfig != null || configuration?.customConfig != null
+                    ? {
+                          ...(this.generator.workspaceConfig.defaultCustomConfig ?? {}),
+                          ...((configuration?.customConfig as Record<string, unknown>) ?? {})
+                      }
+                    : undefined;
+            const publishConfig = configuration?.publishConfig;
+            const outputMode = configuration?.outputMode ?? this.generator.workspaceConfig.defaultOutputMode;
+            const irVersion = this.generator.workspaceConfig.irVersion;
+            const publishMetadata = configuration?.publishMetadata ?? undefined;
+            const readme = configuration?.readmeConfig ?? undefined;
+            const fernWorkspace = await (
+                await convertGeneratorWorkspaceToFernWorkspace({
+                    absolutePathToAPIDefinition,
+                    taskContext,
+                    fixture
+                })
+            )?.toFernWorkspace({ context: taskContext });
+            if (fernWorkspace == null) {
+                return {
+                    type: "failure",
+                    cause: "invalid-fixture",
+                    message: `Failed to validate fixture ${fixture}`,
+                    id: fixture,
+                    outputFolder,
+                    metrics
+                };
+            }
 
-        taskContext.logger.debug("Acquiring lock...");
-        try {
+            taskContext.logger.debug("Acquiring lock...");
             await this.lock.acquire();
             taskContext.logger.info("Running generator...");
             try {