predicate.signal no longer appears to work with switch operator

[brenc]

Description

I was experimenting with this pattern from the book and noticed it no longer appears to work:

jingle_signal = predicate.signal()
radio =
  switch(
    track_sensitive=false, [(jingle_signal, sine(220.)), ({true}, sine(440.))]
  )
thread.run(every=10., {jingle_signal.signal()})

440 plays continuously but 220 (the "jingle") never does. Every time the signal runs, I see this in the logs:

liquidsoap-1  | 2024/12/22 20:14:55 [switch:3] Switch to sine with transition.
liquidsoap-1  | 2024/12/22 20:14:55 [switch:3] Switch to sine.2 with transition.

I'm using sine here but this happens with single, playlist, etc.

Steps to reproduce

Steps above.

Expected behavior

A signal should make the source available.

Liquidsoap version

2.3.0

Liquidsoap build config

* Liquidsoap version  : 2.3.0

 * Compilation options
   - Release build       : true
   - Git SHA             : (none)
   - OCaml version       : 4.14.2
   - OS type             : Unix
   - Libs versions       : alsa=0.3.0 angstrom=0.16.1 ao=0.2.4 asetmap=0.8.1 asn1-combinators=0.3.2 astring=0.8.5 base=v0.16.3 base.base_internalhash_types=v0.16.3 base.caml=v0.16.3 base.shadow_stdlib=v0.16.3 base64=3.5.1 bigarray=[distributed with Ocaml] bigarray-compat=1.1.0 bigstringaf=0.10.0 bjack=0.1.6 bos=0.2.1 bytes=[distributed with OCaml 4.02 or above] ca-certs=v1.0.0 camlp-streams camomile.lib=2.0 cohttp=5.3.1 cohttp-lwt=5.3.0 cohttp-lwt-unix=5.3.0 conduit=7.1.0 conduit-lwt=7.1.0 conduit-lwt-unix=7.1.0 cry=1.0.3 cstruct=6.2.0 ctypes=0.23.0 ctypes-foreign=0.23.0 ctypes.stubs=0.23.0 curl=0.9.2 digestif.c=1.2.0 domain-name=0.4.0 domain_shims dssi=0.1.5 dtools=0.4.5 dune-build-info=3.16.1 dune-private-libs.dune-section=3.16.1 dune-site=3.16.1 dune-site.private=3.16.1 duppy=0.9.4 eqaf=0.10 faad=0.5.2 fdkaac=0.3.3 ffmpeg-av=1.2.1 ffmpeg-avcodec=1.2.1 ffmpeg-avdevice=1.2.1 ffmpeg-avfilter=1.2.1 ffmpeg-avutil=1.2.1 ffmpeg-swresample=1.2.1 ffmpeg-swscale=1.2.1 fileutils=0.6.4 flac=0.5.1 flac.decoder=0.5.1 flac.ogg=0.5.1 fmt=0.9.0 fpath=0.7.3 frei0r=0.1.2 gd=1.1 gen=1.1 gmap=0.3.0 inotify=v2.6 integers ipaddr=5.6.0 ipaddr-sexp=5.6.0 ipaddr.unix=5.6.0 irc-client irc-client-unix kdf.hkdf=1.0.0 kdf.pbkdf=1.0.0 ladspa=0.2.2 lame=0.3.7 lastfm=0.3.4 lilv=0.2.0 liquidsoap-lang=2.3.0 liquidsoap-lang.console=2.3.0 liquidsoap_alsa=v2.3.0-2-g658a641 liquidsoap_ao=v2.3.0-2-g658a641 liquidsoap_bjack=v2.3.0-2-g658a641 liquidsoap_builtins=v2.3.0-2-g658a641 liquidsoap_core=v2.3.0-2-g658a641 liquidsoap_dssi=v2.3.0-2-g658a641 liquidsoap_faad=v2.3.0-2-g658a641 liquidsoap_fdkaac=v2.3.0-2-g658a641 liquidsoap_ffmpeg=v2.3.0-2-g658a641 liquidsoap_flac=v2.3.0-2-g658a641 liquidsoap_frei0r=v2.3.0-2-g658a641 liquidsoap_gd=v2.3.0-2-g658a641 liquidsoap_irc=v2.3.0-2-g658a641 liquidsoap_ladspa=v2.3.0-2-g658a641 liquidsoap_lame=v2.3.0-2-g658a641 liquidsoap_lastfm=v2.3.0-2-g658a641 liquidsoap_lilv=v2.3.0-2-g658a641 liquidsoap_lo=v2.3.0-2-g658a641 liquidsoap_mad=v2.3.0-2-g658a641 liquidsoap_ndi=v2.3.0-2-g658a641 liquidsoap_ogg=v2.3.0-2-g658a641 liquidsoap_ogg_flac=v2.3.0-2-g658a641 liquidsoap_optionals=v2.3.0-2-g658a641 liquidsoap_opus=v2.3.0-2-g658a641 liquidsoap_osc=v2.3.0-2-g658a641 liquidsoap_oss=v2.3.0-2-g658a641 liquidsoap_portaudio=v2.3.0-2-g658a641 liquidsoap_posix_time=v2.3.0-2-g658a641 liquidsoap_prometheus=v2.3.0-2-g658a641 liquidsoap_pulseaudio=v2.3.0-2-g658a641 liquidsoap_runtime=v2.3.0-2-g658a641 liquidsoap_samplerate=v2.3.0-2-g658a641 liquidsoap_sdl=v2.3.0-2-g658a641 liquidsoap_sdl_log_level=v2.3.0-2-g658a641 liquidsoap_shine=v2.3.0-2-g658a641 liquidsoap_soundtouch=v2.3.0-2-g658a641 liquidsoap_speex=v2.3.0-2-g658a641 liquidsoap_sqlite=v2.3.0-2-g658a641 liquidsoap_srt=v2.3.0-2-g658a641 liquidsoap_ssl=v2.3.0-2-g658a641 liquidsoap_stereotool=v2.3.0-2-g658a641 liquidsoap_theora=v2.3.0-2-g658a641 liquidsoap_tls=v2.3.0-2-g658a641 liquidsoap_vorbis=v2.3.0-2-g658a641 liquidsoap_xmlplaylist=v2.3.0-2-g658a641 liquidsoap_yaml=v2.3.0-2-g658a641 lo=0.2.0 logs=0.7.0 logs.fmt=0.7.0 logs.lwt=0.7.0 lwt lwt.unix macaddr=5.6.0 mad=0.5.3 magic-mime=1.3.1 mem_usage=0.1.1 memtrace=0.2.3 menhirLib=20240715 metadata=0.3.0 mirage-crypto=1.1.0 mirage-crypto-ec=1.1.0 mirage-crypto-pk=1.1.0 mirage-crypto-rng=1.1.0 mirage-crypto-rng.unix=1.1.0 mm=0.8.6 mm.audio=0.8.6 mm.base=0.8.6 mm.image=0.8.6 mm.midi=0.8.6 mm.video=0.8.6 ndi=v2.3.0-2-g658a641 ocplib-endian ocplib-endian.bigstring ogg=0.7.4 ogg.decoder=0.7.4 ohex opus=0.2.3 opus.decoder=0.2.3 osc osc-unix portaudio=0.2.3 posix-base=5a7f328 posix-socket=5a7f328 posix-socket.constants=5a7f328 posix-socket.stubs=5a7f328 posix-socket.types=5a7f328 posix-time2=5a7f328 posix-time2.constants=5a7f328 posix-time2.stubs=5a7f328 posix-time2.types=5a7f328 posix-types=5a7f328 posix-types.constants=5a7f328 ppx_compare.runtime-lib=v0.16.0 ppx_hash.runtime-lib=v0.16.0 ppx_sexp_conv.runtime-lib=v0.16.0 prometheus=1.2 prometheus-app=1.2 ptime=1.2.0 ptime.clock=1.2.0 ptime.clock.os=1.2.0 pulseaudio=0.1.6 re=1.12.0 result=1.5 rresult=0.7.0 samplerate=0.1.7 saturn_lockfree=0.4.1 sedlex=3.3 seq=[distributed with OCaml 4.07 or above] sexplib0=v0.16.0 shine=0.2.3 soundtouch=0.1.9 speex=0.4.2 speex.decoder=0.4.2 sqlite3=5.2.0 srt=0.3.1 srt.constants=0.3.1 srt.stubs=0.3.1 srt.stubs.locked=0.3.1 srt.types=0.3.1 ssl=0.7.0 stdlib-shims=0.3.0 stereotool=v2.3.0-2-g658a641 str=[distributed with Ocaml] stringext=1.6.0 theora=0.4.1 theora.decoder=0.4.1 threads=[distributed with Ocaml] threads.posix=[internal] tls=1.0.2 tsdl=v1.1.0 tsdl-image=0.5 tsdl-ttf=0.6 unix=[distributed with Ocaml] unix-errno=52c6ecb unix-errno.errno_bindings=52c6ecb unix-errno.errno_types=52c6ecb unix-errno.errno_types_detected=52c6ecb unix-errno.unix=52c6ecb uri=4.4.0 uri-sexp=4.4.0 uri.services=4.4.0 vorbis=0.8.1 vorbis.decoder=0.8.1 x509=1.0.5 xmlm=1.4.0 xmlplaylist=0.1.5 yaml=3.2.0 yaml.bindings=3.2.0 yaml.bindings.types=3.2.0 yaml.c=3.2.0 yaml.ffi=3.2.0 yaml.types=3.2.0 zarith=1.14
   - architecture        : amd64
   - host                : x86_64-pc-linux-gnu
   - target              : x86_64-pc-linux-gnu
   - system              : linux
   - ocamlopt_cflags     : -O2 -fno-strict-aliasing -fwrapv -pthread -fPIC
   - native_c_compiler   : gcc -O2 -fno-strict-aliasing -fwrapv -pthread -fPIC -D_FILE_OFFSET_BITS=64
   - native_c_libraries  : -lm

 * Configured paths
   - mode              : posix
   - standard library  : /usr/share/liquidsoap/libs
   - scripted binaries : /usr/share/liquidsoap/bin
   - rundir            : /var/run/liquidsoap
   - logdir            : /var/log/liquidsoap
   - user cache        : $HOME/.cache/liquidsoap (override with $LIQ_CACHE_USER_DIR)
   - system cache      : /var/cache/liquidsoap (override with $LIQ_CACHE_SYSTEM_DIR)
   - camomile files    : /usr/share/liquidsoap/camomile

 * Supported input formats
   - MP3               : yes
   - AAC               : yes
   - Ffmpeg            : yes
   - Flac (native)     : yes
   - Flac (ogg)        : yes
   - Opus              : yes
   - Speex             : yes
   - Theora            : yes
   - Vorbis            : yes
   - WAV/AIFF          : yes (native)

 * Supported output formats
   - FDK-AAC           : yes
   - FFmpeg            : yes
   - MP3               : yes
   - MP3 (fixed-point) : yes
   - Flac (native)     : yes
   - Flac (ogg)        : yes
   - Opus              : yes
   - Speex             : yes
   - Theora            : yes
   - Vorbis            : yes
   - WAV/AIFF          : yes (native)

 * Tags
   - AAC               : yes
   - FFmpeg            : yes
   - FLAC (native)     : yes
   - Flac (ogg)        : yes
   - Native decoder    : yes
   - Vorbis            : yes

 * Input / output
   - ALSA              : yes
   - AO                : yes
   - FFmpeg            : yes
   - JACK              : yes
   - NDI               : yes
   - OSS               : yes
   - Portaudio         : yes
   - Pulseaudio        : yes
   - SRT               : yes

 * Audio manipulation
   - FFmpeg            : yes
   - LADSPA            : yes
   - Lilv              : yes
   - Samplerate        : yes
   - SoundTouch        : yes
   - StereoTool        : yes

 * Video manipulation
   - camlimages        : no (requires camlimages)
   - FFmpeg            : yes
   - frei0r            : yes
   - ImageLib          : no (requires imagelib)
   - SDL               : yes

 * MIDI manipulation
   - DSSI              : yes

 * Visualization
   - GD                : yes
   - Graphics          : no (requires graphics)
   - SDL               : yes

 * Additional libraries
   - FFmpeg filters    : yes
   - FFmpeg devices    : yes
   - inotify           : yes
   - irc               : yes
   - jemalloc          : no (requires jemalloc)
   - lastfm            : yes
   - lo                : yes
   - memtrace          : yes
   - osc               : yes
   - ssl               : yes
   - sqlite3           : yes
   - tls               : yes
   - posix-time2       : yes
   - windows service   : no (requires winsvc)
   - YAML support      : yes
   - XML playlists     : yes

 * Monitoring
   - Prometheus        : yes

Installation method

From official container image

Additional Info

No response