rustc-dev-guide/src/rustc-driver-getting-diagnostics.md

Example: Getting diagnostic through rustc_interface

rustc_interface allows you to intercept diagnostics that would otherwise be printed to stderr.

Getting diagnostics

To get diagnostics from the compiler, configure rustc_interface::Config to output diagnostic to a buffer, and run TyCtxt.analysis. The following was tested with nightly-2023-03-27:

{{#include ../examples/rustc-driver-getting-diagnostics.rs}}