Fixes#2460Fixes#2851
Ref #2707, #2708, #2469
Unlike the previous attempts at fixing the handling of build-level
keys, this change does not change the main parsing logic, which uses
`getKey` to retrieve the key from the key map.
The fact that shell worked pre-0.13.11 means that the parsing was ok.
What this changes is just the "example" keys supplied to the parser so
the tab completion works.
Fixes#2761
With sbt 0.13.13-RC1 rediscovered that the dependency pulled in from
Giter8 was affecting the plugins. To avoid this, this change splits up
the template resolver implementation to another module called
sbt-giter8-resolver, and it will be downloaded using Ivy into
`~/.sbt/0.13/templates/`, and then launched reflectively using Java as
the interface.
This adds `new` command, which helps create a new build definition. The
`new` command is extensible via a mechanism called the template
resolver,
which evaluates the arbitrary arguments passed to the command to find
and run a template.
As a reference implementation [Giter8][g8] is provided as follows:
sbt new eed3si9n/hello.g8
This will run eed3si9n/hello.g8 using Giter8.
[g8]: http://www.foundweekends.org/giter8/
The compiler interface subclasses `scala.tools.nsc.Global`,
and loading this new subclass before each `compile` task forces
HotSpot JIT to deoptimize larges swathes of compiled code. It's
a bit like SBT has rigged the dice to always descend the longest
ladder in a game of Snakes and Ladders.
The slowdown seems to be larger with Scala 2.12. There are a number
of variables at play, but I think the main factor here is that
we now rely on JIT to devirtualize calls to final methods in traits
whereas we used to emit static calls. JIT does a good job at this,
so long as classloading doesn't undo that good work.
This commit extends the existing `ClassLoaderCache` to encompass
the classloader that includes the compiler interface JAR. I've
resorted to adding a var to `AnalyzingCompiler` to inject the
dependency to get the cache to the spot I need it without binary
incompatible changes to the intervening method signatures.