Test suite: If the deprecation_exec test fails, print the subcommand's stdout and stderr to the log
#46059
Conversation
…d's `stdout` and `stderr` to the log
| flags = Cmd(filter(a->!occursin("depwarn", a), collect(test_exeflags))) | ||
| cmd = `$test_exename $flags --depwarn=yes deprecation_exec.jl` | ||
| io = IOBuffer() | ||
| pipln = pipeline(cmd; stdout=io, stderr=io) |
There was a problem hiding this comment.
I'm away from computer and can't check myself: can you have stdout and stderr writing to the same buffer? It's nice if that just works, I guess it'd be similar to &> redirection in shell.
There was a problem hiding this comment.
From a quick test, it seems to work fine.
julia> println(read("foo.jl", String))
println(stdout, "out1")
println(stderr, "err1")
println(stdout, "out2")
println(stderr, "err2")
println(stdout, "out3")
println(stderr, "err3")
julia> cmd = `julia foo.jl`;
julia> io = IOBuffer();
julia> run(pipeline(cmd; stdout=io, stderr=io));
julia> println(String(take!(io)))
out1
err1
out2
err2
out3
err3
julia>
There was a problem hiding this comment.
You are not allowed to use an IOBuffer as output, as such types are not stream-oriented, so they lack the required EOF capabilities. Use a BufferStream instead
There was a problem hiding this comment.
I've switched this PR to use Base.BufferStream().
There was a problem hiding this comment.
@vtjnash Is it legal for me to send both stdout and stderr to the same BufferStream? E.g.
io = Base.BufferStream()
run(pipeline(cmd; stdout=io, stderr=io))
close(io)
There was a problem hiding this comment.
Not really. It will result in the program getting 2 different streams, while you probably wanted it to get only one file description
There was a problem hiding this comment.
Hmmm. What's the correct way to capture the stdout and stderr from a command into a single string?
This should help a little bit when trying to diagnose failures in the
deprecation_exectest set (e.g. the failures seen in #46039).