Missing newline in "dune exec -w"

[muzimuzhi]

Expected Behavior

When running "dune exec" with watch mode on (-w/--watch), it would be better to show program's output on a new line. Currently it's appended to the message "Success, waiting for filesystem changes...".

Similar to #7142 but with watch mode on.

Success, waiting for filesystem changes...
Hello, dune!

Actual Behavior

Success, waiting for filesystem changes...Hello, dune!

Reproduction

$ dune init project test
Entering directory '/private/tmp/test'
Success: initialized project component named test

$ cd test
$ dune exec -w test
Success, waiting for filesystem changes...Hello, World!
Hello, World!
Success, waiting for filesystem changes...
Success, waiting for filesystem changes...Hello, dune!

Specifications

• Version of dune (output of dune --version): 3.16.0
• Version of ocaml (output of ocamlc --version): 5.2.0
• Operating system (distribution and version): macOS 14.6.1 (darwin23.0)

[gridbugs]

I believe this is fixed now. @muzimuzhi can you test it out and let us know if #10983 solved the issue you were encountering?

[muzimuzhi]

I tried compiling dune from source but make release failed with

$ make release
Internal error, please report upstream including the contents of _build/log.
Description:
  ("Unexpected find result", { found = Not_found; lib.name = "pp" })
Raised at Stdune__Code_error.raise in file
  "otherlibs/stdune/src/code_error.ml", line 10, characters 30-62
Called from Fiber__Scheduler.exec in file "vendor/fiber/src/scheduler.ml",
  line 76, characters 8-11
-> required by ("<unnamed>", ())
-> required by ("<unnamed>", ())
-> required by ("<unnamed>", ())
-> required by ("load-dir", In_build_dir "default/test/blackbox-tests/utils")
-> required by ("toplevel", ())

I must not crash.  Uncertainty is the mind-killer. Exceptions are the
little-death that brings total obliteration.  I will fully express my cases.
Execution will pass over me and through me.  And when it has gone past, I
will unwind the stack along its path.  Where the cases are handled there will
be nothing.  Only I will remain.
make: *** [release] Error 1

$ cat _build/log

# ./_boot/dune.exe build @install -p dune --profile dune-bootstrap
# OCAMLPARAM: unset
# Shared cache: enabled-except-user-rules
# Shared cache location: /Users/username/.cache/dune/db
# Workspace root: /Users/username/Projects/dune
# Auto-detected concurrency: 12
# Dune context:
#  { name = "default"
#  ; kind = "default"
#  ; profile = User_defined "dune-bootstrap"
#  ; merlin = true
#  ; fdo_target_exe = None
#  ; build_dir = In_build_dir "default"
#  ; instrument_with = []
#  }
$ /Users/username/.opam/cs3110-2024fa/bin/ocamlc.opt -config > /var/folders/w9/x27qzw1913v53ry3lz2z3_pm0000gn/T/dune_63960d_output