message: Fail tests if diagnostics are returned on open
  Summary: Tested files should generally lint clean. If a need for getting errors on open is required later, we can add that capability in.
diff: @@ -48,7 +48,6 @@ use lsp_types::InitializeParams;
  use lsp_types::InitializeResult;
  use lsp_types::InitializedParams;
  use lsp_types::Position;
  -use lsp_types::PublishDiagnosticsParams;
  use lsp_types::Range;
  use lsp_types::TextDocumentClientCapabilities;
  use lsp_types::TextDocumentContentChangeEvent;
  @@ -550,11 +549,9 @@ impl TestServer {
  }
  /// Send a notification saying that a file was opened with the given contents.
  - pub fn open_file(
  - &mut self,
  - uri: Url,
  - contents: String,
  - ) -> anyhow::Result<PublishDiagnosticsParams> {
  + ///
  + /// This will return an error if there were any diagnostic messages.
  + pub fn open_file(&mut self, uri: Url, contents: String) -> anyhow::Result<()> {
  let open_params = DidOpenTextDocumentParams {
  text_document: TextDocumentItem {
  uri: uri.clone(),
  @@ -572,8 +569,13 @@ impl TestServer {
  notification.uri,
  uri
  ))
  + } else if !notification.diagnostics.is_empty() {
  + Err(anyhow::anyhow!(
  + "Got unexpected diagnostic messages when opening {}",
  + uri
  + ))
  } else {
  - Ok(notification)
  + Ok(())
  }
  }
  