Code Inspection: Missing '.ConfigureAwait(false)' in library code
This inspection suggests adding
ConfigureAwait(false) calls to awaitables in the scope where ConfigureAwait analysis is enabled in the Library mode.
ConfigureAwait() calls work and their usage scenarios are explained in detail in this Microsoft .NET Blog article as well as in many other posts that you can find on the Internet, but the usage advice for
ConfigureAwait() boils down to the following:
To improve performance and avoid potential deadlocks, use
ConfigureAwait(false)in any non-UI code. The exception here is app-level code, such as Windows Forms, WPF, and ASP.NET.
ConfigureAwait(true)corresponds to the default behavior and does nothing meaningful, therefore such calls can be safely omitted.
To analyze usages of
ConfigureAwait(), ReSharper needs to know whether it is application-level code or general-purpose library code. By default, the ConfigureAwait analysis is disabled and you need to enable the analysis in each project choosing one of the two modes:
Library mode — ReSharper will suggest adding
ConfigureAwait(false)calls to awaitables.
UI mode — ReSharper will report
ConfigureAwait(true)calls as redundant.
Enable ConfigureAwait analysis and choose its mode
To enable ConfigureAwait analysis in a project, right-click the project in the Solution Explorer, select Library or UI., and then choose
To enable ConfigureAwait analysis in the current project, place the caret at any
awaitkeyword, press Alt+Enter, select ConfigureAwait analysis and then choose Library or UI.
If you use EditorConfig, you can specify the ConfigureAwait analysis mode for a project, a folder, or a file with the following properties:
configure_await_analysis_mode = libraryor
configure_await_analysis_mode = ui.