This builds on #2231 but was actually done before that. You see, the
cause for #2231 was that I got this error message:
Error: Error { kind: Io(Os { code: 2, kind: NotFound, message: "No such file or directory" }) }
Just switching to `anyhow::Result` got me stack traces (when setting
`RUST_LIB_BACKTRACE=1`) that at least showed
stack backtrace:
0: std::backtrace::Backtrace::create
1: std::backtrace::Backtrace::capture
2: anyhow::error::<impl core::convert::From<E> for anyhow::Error>::from
3: xtask::install_server
4: xtask::install
5: xtask::main
6: std::rt::lang_start::{{closure}}
7: std::panicking::try::do_call
8: __rust_maybe_catch_panic
9: std::rt::lang_start_internal
10: std::rt::lang_start
11: main
With the added contexts (not at all exhaustive), the error became
Error: install server
Caused by:
0: build AutoCfg with target directory
1: No such file or directory (os error 2)
Since anyhow is such a small thing (no new transitive dependencies!),
and in general gives you `Result<T, Box<dyn Error>>` on steroids, I
think this a nice small change. The only slightly annoying thing was to
replace all the `Err(format!(…))?` calls (haven't even looked at whether
we can make it support wrapping strings though), but the `bail!` macro
is shorter anyway :)
