A slow or heavily-loaded fleet box can occasionally flake a concurrency-
sensitive test (e.g. a daemon/lsh test under -j8 on a nested-VM Solaris box).
Rather than dropping the whole target to a lower -j, add a per-target
"max_retry" property: after a run, each failed test is re-run on its own up to
max_retry more times, and any that then pass are dropped from the failure list.
Recovered tests are listed in a new "RECOVERED" report section, so a flake is
surfaced, never silently hidden.
Applies to every pass for the target (pipe, tcp, protoNN, nonroot). Default 0
keeps the current no-retry behaviour.
A target can list older "protocols" (e.g. [30, 29]) in the fleet config;
each runs as an extra stdio-pipe pass with runtests --protocol=N, the fleet
analogue of a workflow's check30/check29 steps. The passes reuse the same
parsed RSYNC_EXPECT_SKIPPED list as the default pipe run and appear as protoNN
columns in the report and --timing breakdown. Targets without the key run only
the default protocol and show "-" there.
The example config's ubuntu-2604 target (mirroring ubuntu-build.yml, which has
check30/check29 steps) now sets protocols: [30, 29].
fleettest.py builds the committed HEAD of a checkout on a fleet of remote machines over ssh and runs the test suite under both the stdio-pipe and --use-tcp transports in parallel, reporting only the unexpected results. Each target mirrors a .github/workflows/*.yml job: its configure flags, and the RSYNC_EXPECT_SKIPPED list parsed from the workflow.
The fleet is described by a JSON file (testsuite/fleettest.json, git-ignored); fleettest.json.example is a worked template. Use --fleet to point at another config and --repo to build a tree other than the current directory.
A target with nonroot:true reruns, as the unprivileged ssh user, the tests that declare a module-level fleet_nonroot=True (here ownership-depth and daemon). The set lives in the test files, so new privilege-sensitive tests join the non-root pass with no fleet-config change.
Also rename testsuite/README.testsuite to README.md and rewrite it as markdown documenting the current testsuite: runtests.py, the make check/check29/check30/installcheck/coverage targets, the result/exit-code conventions, and fleettest.py.
