appendix: 23 Code-Ausschnitte aus dem Houston-Repository

Pin nixpkgs to the revision used by itc.componentware: the channel version
ships a latexminted that crashes on Python 3.14, which made every listing
fail and sent latexmk into an endless error prompt. Also force
nonstopmode/halt-on-error so a broken listing can never loop again.

figures/code/tests-empty-bucket.cs

@@ -0,0 +1,44 @@
+
+/// <summary>
+/// A bucket without a single object: every lookup answers with a 404 and every listing is empty
+/// until a test puts something in via <see cref="GiveFolder"/>, <see cref="GiveTopLevelFolders"/>
+/// or <see cref="GiveObjects"/>.
+/// </summary>
+private static IAmazonS3 EmptyBucket()
+{
+    var s3 = Substitute.For<IAmazonS3>();
+
+    // Objects written during the test become visible to later lookups, just like in a real bucket.
+    var writtenObjects = new Dictionary<string, string?>(StringComparer.Ordinal);
+
+    s3.GetObjectMetadataAsync(Arg.Any<GetObjectMetadataRequest>(), Arg.Any<CancellationToken>())
+        .Returns(call =>
+        {
+            var key = call.Arg<GetObjectMetadataRequest>().Key;
+
+            if (!writtenObjects.TryGetValue(key, out var owner))
+                throw new AmazonS3Exception("not found") { StatusCode = System.Net.HttpStatusCode.NotFound };
+
+            return owner is null ? new GetObjectMetadataResponse() : MetadataResponse(owner);
+        });
+
+    s3.ListObjectsV2Async(Arg.Any<ListObjectsV2Request>(), Arg.Any<CancellationToken>())
+        .Returns(_ => new ListObjectsV2Response { IsTruncated = false });
+
+    s3.CopyObjectAsync(Arg.Any<CopyObjectRequest>(), Arg.Any<CancellationToken>())
+        .Returns(_ => new CopyObjectResponse());
+
+    s3.PutObjectAsync(Arg.Any<PutObjectRequest>(), Arg.Any<CancellationToken>())
+        .Returns(call =>
+        {
+            var request = call.Arg<PutObjectRequest>();
+            writtenObjects[request.Key] = request.Metadata["efecte-org-id"];
+            return new PutObjectResponse();
+        });
+
+    s3.DeleteObjectsAsync(Arg.Any<DeleteObjectsRequest>(), Arg.Any<CancellationToken>())
+        .Returns(_ => new DeleteObjectsResponse());
+
+    return s3;
+}
+