The adb wrapper can only aim a call that goes through it, and Gradle's
Android tasks do not: installDebug, uninstallDebug and connectedAndroidTest
ask the adb server for every attached device and act on all of them. One
session ran installDebug with two emulators up and replaced the app on both,
which Gradle reported as success and the other session read as its own build
never landing.
`emu check` answers the question the wrapper already answers for adb --
would a command that reaches every attached device reach a stranger's
emulator from here -- and install.sh links a Gradle init script into
~/.gradle/init.d so every build on this machine asks it, including checkouts
nobody has adopted it in.
It refuses narrowly: a lone emulator, a physical phone and a caller who
named a device are all fine. ANDROID_SERIAL naming another checkout's
emulator is not, because that is what a serial exported into a long-lived
shell decays into once an emulator restarts and another's takes the port.
ui-trace, the adb wrapper and its device recorder were loose files under
~/.local, and each Android checkout carried its own copy of the same
emulator boot sequence. This puts them together, with an install script that
symlinks them back so editing the repo is editing what runs.
Two things are new rather than moved. `emu` is the emulator lifecycle --
name, serial, list, up, down -- keyed on the AVD named after the enclosing
checkout, which is the rule that lets several sessions work here at once;
and `adb` now fills in `-s` from that same rule, because with two emulators
attached a bare `adb shell pm list packages` comes back empty rather than
failing, which reads as the app being uninstalled rather than the question
being ambiguous.
`emu up` refuses when the machine has no room. On 2026-08-30 an emulator
started with 2.8 GB available invoked the OOM killer, and what it took was
not the emulator that had just started: it walked the user slice and killed
pipewire, dbus-broker and another session's emulator first.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
iris
