I installed the latest Xcode : v10 (10A255) on macOS Mojave v10.14 (18A391)
> swift --version
Apple Swift version 4.2 (swiftlang-1000.0.37.1 clang-1000.10.44)
> swift build
used to build my project (which uses other packages)
but now I get:
> swift build
error: terminated(72): xcrun --sdk macosx --find xctest output:
I'm not trimming anything here; there's nothing after "output:" the following line is empty.
I can create a new package "swift init --type executable"; but I'll have the same error if I try to build it.
I can't tell what's wrong here and my internet search is unfruitful so far.