autospider.py is intended both as the harness for running automation builds, as
well as a way to easily reproduce automation builds on a developer workstation.
Some brave souls also use it as the basis for doing their normal local builds.

Basic usage:

  ./js/src/devtools/automation/autospider.py plain

The script may be run from any directory. This will configure and build the
source, then run a series of tests. See the --help message for many different
ways of suppressing various actions or changing the output.

The different possible build+test configurations are controlled mostly by JSON
files in a variants/ directory (eg there is a .../variants/plain file for the
above command).

In automation, the test jobs will run with a dynamically loaded library that
catches crashes and generates minidumps, so that autospider.py can produce a
readable stack trace at the end of the run. Currently this library is only
available on linux64, and is built via the following procedure:

    % git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git
    % export PATH=$PATH:$(pwd)/depot_tools
    % mkdir breakpad
    % cd breakpad
    # python must be python2.7
    % fetch breakpad
    % cd src
    % git fetch https://github.com/hotsphink/breakpad injector
    % git checkout FETCH_HEAD
    % cd ..
    % mkdir obj
    % cd obj
    # Possibly set $PATH to include a recent gcc
    % ../src/configure --enable-static
    % mkdir ../root
    % make install DESTDIR=$(pwd)/../root

The shared library will now be in root/usr/local/lib64/libbreakpadinjector.so
