[swift-users] Debugging XCTests on Linux

[Robert Atkins]

Hi all,

I'm trying to solve a simple (?) problem where a test suite runs fine on
macOS but fails on Linux
(https://github.com/antitypical/Result/pull/210#pullrequestreview-14963305).
I've downloaded and installed the Swift Linux Docker image
(https://ashfurrow.com/blog/swift-on-linux/) and got the project
building and testing, and, mercifully, I get the same failure locally as
I'm getting on Travis CI. But at this point I'm stuck.

1) I can't get the SPM-built module the project produces working
properly in the Swift REPL in order to just play around with it
(https://bugs.swift.org/browse/SR-1191). Can anyone help me with this?

2a) How do I use LLDB to set a breakpoint in a test method and step into
its execution so I can trace through the source of the test failure?
Saying "lldb swift test" does something, but doesn't know about any of
the lines I'm trying to set a breakpoint on—I suspect it thinks I'm
trying to set breakpoints in the swift binary itself, rather than the
test suite?

2b) Saying "swift -warnings-as-errors test" doesn't seem to do what I
want, complaining about "no such file or directory: 'test'", whereas
"swift test" works fine. Is there a way to pass flags to the swift
interpreter when it runs tests? 

Thanks, Robert.