test(generator): golden files for openapi (#66)

This introduces (incomplete, not usable) golden files for the openapi branch of
the generator. I decided to just regenerate the golden files on each run, and
then let `git diff` detect any changes.

generator/cmd/openapi/main_test.go

@@ -0,0 +1,32 @@
+// Copyright 2024 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"flag"
+	"os"
+	"testing"
+)
+
+func TestMain(m *testing.M) {
+	flag.Parse()
+	os.Exit(m.Run())
+}
+
+func TestRun_Rust(t *testing.T) {
+	if err := run("testdata/secretmanager_openapi_v1.json", "rust", "testdata/rust/golden", "../../templates"); err != nil {
+		t.Fatal(err)
+	}
+}

generator/cmd/openapi/testdata/rust/golden/lib.rs

@@ -0,0 +1,28 @@
+use std::sync::Arc;
+
+pub mod model;
+
+#[derive(Clone, Debug)]
+pub struct Client {
+    inner: Arc<ClientRef>,
+}
+
+#[derive(Debug)]
+struct ClientRef {
+    http_client: reqwest::Client,
+    token: String,
+}
+
+impl Client {
+    pub fn new(tok: String) -> Self {
+        let client = reqwest::Client::builder().build().unwrap();
+        let inner = ClientRef {
+            http_client: client,
+            token: tok,
+        };
+        Self {
+            inner: Arc::new(inner),
+        }
+    }
+}
+