Proxies created by Import are undefined

[costleya]

var artifactBucket = BucketRef.Import(this, "PipelineArtifactBucket", new BucketRefProps()
{
    BucketName = "TestBucket"
});
var pipeline = new Pipeline(this, "Pipeline", new PipelineProps
{
    ArtifactBucket = artifactBucket,
    RestartExecutionOnUpdate = true
});
Console.WriteLine(pipeline.ArtifactBucket.BucketName == artifactBucket.BucketName);

Returns False.

var codeCommit = RepositoryRef.Import(this, "CodeCommit", new RepositoryRefProps
{
    RepositoryName = "test-repo"
});
new PipelineSourceAction(this, "CodeCommitSourceAction",
    new PipelineSourceActionProps
    {
        Stage = sourceStage,
        Branch = "master",
        Repository = codeCommit
    });

Throws an exception - "Unhandled Exception: Amazon.JSII.Runtime.JsiiException: Cannot read property 'repositoryName' of undefined."

[costleya]

The thrown are now "Interfaces should not used directly, bindings should use a proxy type" (paraphrase).