view tests/test-hghave.t @ 30761:7283719e2bfd

util: declare wire protocol support of compression engines

This patch implements a new compression engine API allowing
compression engines to declare support for the wire protocol.

Support is declared by returning a compression format string
identifier that will be added to payloads to signal the compression
type of data that follows and default integer priorities of the
engine.

Accessor methods have been added to the compression engine manager
class to facilitate use.

Note that the "none" and "bz2" engines declare wire protocol support
but aren't enabled by default due to their priorities being 0. It
is essentially free from a coding perspective to support these
compression formats, so we do it in case anyone may derive use from
it.

Testing that hghave does not crash when checking features

  $ hghave --test-features 2>/dev/null

Testing hghave extensibility for third party tools

  $ cat > hghaveaddon.py <<EOF
  > import hghave
  > @hghave.check("custom", "custom hghave feature")
  > def has_custom():
  >     return True
  > EOF

(invocation via run-tests.py)

  $ cat > test-hghaveaddon.t <<EOF
  > #require custom
  >   $ echo foo
  >   foo
  > EOF
  $ run-tests.py $HGTEST_RUN_TESTS_PURE test-hghaveaddon.t
  .
  # Ran 1 tests, 0 skipped, 0 warned, 0 failed.

(invocation via command line)

  $ unset TESTDIR
  $ hghave custom

(terminate with exit code 2 at failure of importing hghaveaddon.py)

  $ rm hghaveaddon.*
  $ cat > hghaveaddon.py <<EOF
  > importing this file should cause syntax error
  > EOF

  $ hghave custom
  failed to import hghaveaddon.py from '.': invalid syntax (hghaveaddon.py, line 1)
  [2]