If node is already in PATH and functional, we don't need to spend a
bunch of time running all of Boxen's setup scripts.
This reduces clean build time on my MacBook Pro from 46 seconds to 31
seconds.
Instead of finding and compiling all .coffee/.cson files in
script/copy-files-to-bundle, we now tell gyp how to do this for us. It
works like this:
1. Rakefile invokes the new script/generate-sources-gypi script to
generate sources.gypi. This file lists all the .coffee/.cson files in
the src, static, and vendor directories, as well as a new
compiled_sources_dir variable that specifies where the compiled
versions of the files should be placed.
2. atom.gyp includes sources.gypi.
3. atom.gyp has a new target, generated_sources, which contains all the
.coffee/.cson files, and uses two rules to tell gyp how to compile
them. The rules invoke the new script/compile-coffee and
script/compile-cson files once for each file.
4. gyp generates one Makefile for each rule to actually perform the
compilation.
5. script/copy-files-to-bundle now takes the compiled_sources_dir
variable as an argument, and copies files both from there and from
the repository into the Resources directory.
By putting the compilation into a different target, we can do it in
parallel with compiling/linking our binaries. And gyp automatically runs
make using -j$(sysctl -n hw.ncpu), so compilation of .coffee/.cson files
happens in parallel, too.
These changes reduce clean build time on my MacBook Pro from 55 seconds
to 46 seconds.
