Every file tsc-ts reads goes through scriptc's file system callbacks,
including the ~80 files of tsc-ts's own default library directory: one
round trip from the checker to the compiler and back for each. Those
files belong to the installed tsc-ts (the build caches key on its
executable's identity), and no build serves them differently.
When tsc-ts takes --default-libraries-from-disk, the native compiler
passes it to the checker it starts and to the shared checker server, so
tsc-ts reads those files itself; every other path keeps the callbacks.
Released tsc-ts versions reject the flag, so checker-features.ts asks
each tsc-ts executable once (tsc-ts --api --default-libraries-from-disk
with an empty input exits with 0 only when it knows the flag) and keeps
the answer in the native cache, keyed by the executable's identity. With
a tsc-ts that does not know the flag, builds run as before.
Edit builds of small programs through the shared checker server are
about 18 ms faster, and 6-9 ms faster without it.
With SCRIPTC_CHECKER_SERVER=1 on Linux and macOS, the native compiler's
checker connections go to a shared `tsc-ts --api --listen` server, which
keeps the files it parsed for the next build. When the variable is unset,
nothing changes.
checkerServerName names the server by a digest of the tsc-ts executable's
identity, the working directory, the file system callbacks, the timing
flag and the TSC_TS_* environment. scriptc_ts7_attach takes the server's
lock file with a non-blocking flock, connects to its socket in this
user's private server directory ($XDG_RUNTIME_DIR/scriptc or
/tmp/scriptc-<uid>), and starts the server when none answers: in its own
process group, with its standard streams on /dev/null and no other
descriptor of the build, with --idle-exit 300 and TSC_TS_LISTEN_MEMORY=2048
unless the environment sets it. A build that finds the server in use,
cannot start or reach it, or gets no answer to a ping checks with its own
tsc-ts process, as without the variable; so does a tsc-ts without
--listen, which exits as it starts. The syntax-only source parser, which
reads no libraries, always uses its own process and leaves the server to
the program's checker.
- Launch and manage TypeScript server processes through a portable native FFI boundary.
- Share the production session API between Node and statically compiled clients.
- Preserve Unicode command-line arguments and release server resources on every exit path.
Chris Tate