Since commit d10e1148 "Add initial support for preinstalling flatpaks",
the test suite sets FLATPAK_DATA_DIR to a temporary directory, both
while running uninstalled and as-installed.
While running uninstalled we already set FLATPAK_TRIGGERSDIR to the
trigger scripts in the source tree, but when running "as-installed",
we need to run the triggers that the OS installs as part of the flatpak
package (or equivalent).
Not having this caused autopkgtests (automated as-installed tests) in
Debian to regress with 1.17.x.
Fixes: d10e1148 "Add initial support for preinstalling flatpaks"
Signed-off-by: Simon McVittie <smcv@debian.org>
c324778b07
