These classloaders which are created if sbt is launched with a legacy
launcher (or one that doesn't follow the current classloading hierarchy
convention), were implemented in scala, but that meant that they were
not parallel capable. I fix that by moving the implementations to java.
I also move the static method that creates a MetaBuildLoader into the
java class.
A number of users were reporting issues with deadlocking when using
1.3.2: https://github.com/sbt/sbt/issues/5116. This seems to be because
most of the sbt created classloaders were not actually parallel capable.
In order for a classloader to be registered as a parallel capable, ALL
of the parent classes except for object in the class hierarchy must be
registered as a parallel capable:
https://docs.oracle.com/javase/8/docs/api/java/lang/ClassLoader.html#registerAsParallelCapable--.
If a classloader is not registered as parallel capable, then a global
lock will be used internally for classloading and this can lead to deadlock.
It is impossible to register a scala 2 classloader as parallel capable
so I ported all of the classloaders to java.
This commit updates the java-serialization scripted test. Prior to the
port, the new version of the test would more or less always deadlock.
After this change, I haven't been able to reproduce a deadlock.
This had no significant performance impact when I reran
https://github.com/eatkins/scala-build-watch-performance
Fixes#1458
Running sbt from `/` results to sbt getting stuck trying to load the directories recursively, and eventually erroring with a java.lang.OutOfMemoryError (after freezing for a long time) even on an Alpine container.
To prevent it, this adds a check to see if the absolute path is `/` or not.
```
/ $ sbt -Dsbt.version=1.4.0-SNAPSHOT
[error] java.lang.IllegalStateException: cannot run sbt from root directory without -Dsbt.rootdir=true; see sbt/sbt#1458
[error] Use 'last' for the full log.
```
The message:
```
Project loading failed: (r)etry, (q)uit, (l)ast, or (i)gnore?
```
is not explicit about retry being the option used when pressing return.
Fixessbt/sbt#2695
By the time the arguments are passed to a batch script,
it seems like is parsed away.
for /F did not work since it would not handle double quoted
paths that include whitespaces.
This adds special handling for -D parameters only.
On the off chance that in some configurations the terminal width is set
to zero, avoid an exception by returning 0 for terminal lines. It is
likely that supershell will not work well if terminal width is zero, but
that's better than a potential crash (I think the crash would be in the
progress background thread, so I'm not sure how bad it would be, but
still its good to avoid).
It is necessary to close the run classloader in order to reuse the
dependency layer in the next run. If the loader needs to survive past
the main method, as is the case with `run` and `runMain`, then the
runWithLoader api should be used instead.
This mostly restores the behavior of classloader closing to 1.3.0 for
the tasks that use ScalaRun except for `run` and `runMain`. But unlike
1.3.0, if the classloader is closed it can still spawn a zombie
classloader.
Fixes#5124.
I don't think that dummy tasks really make sense for task progress
because they are evaluated outside of the normal task evaluation. This
came up because I was seeing streams-manager in supershell which didn't
seem useful.
I noticed some flickering in super shell progress lines and realized
that it was because there were multiple progress threads running
concurrently. This is problematic because each thread has a completely
different state so if each thread has an active task, the display will
flicker between the two tasks. I think this is caused primarily by
dynamic tasks. At least the example where I was seeing it was caused by
a dynamic task.
Sometimes if the progress lines are wider than the terminal width,
the supershell blank zone can expand indefinitely because be do not move
the cursor far enough up to properly re-fill the blank zone.
If a project had a meta-meta build (project/project), the build sources
in the project directory were ignored. This was because the projectGlobs
method did not correctly handle recursion. It inadvertently
discarded the accumulator globs and only returned the most recently
generated globs. This commit fixes that and adds a regression test to
the nio/reload scripted test.
I was looking into sbt start up time and in profiling was able to
identify a number of classloading bottlenecks. To speed up
initialization, we can preload those classes in the background. I saw
average speedups of roughly .75 seconds after this change. Also, the `time`
command would consistently report cpu system time very close to 400% and
I have 4 cores on my laptop. With 1.3.0 it would be more like 350%.
There have been a number of complaints about the new classloader closing
behavior. It is too aggressive about closing classloaders after test and
run. This commit softens the behavior by allowing a classloader to be
resurrected after close by creating a new zombie classloader that has
the same urls as the original classloader. After this commit, we always
close the classloaders when we are done, but they can still leak
file descriptors if a zombie is created.
To configure the behavior, I add the allowZombieClassLoaders key. If it
is false (which is default), we will warn but still allow them. If it
is true, then we silence the warning. In a later version of sbt, we can
change the semantics to be strict.
I verified after this change that I could add a shutdown hook in `run`
and it would be evaluated so long as I set `bgCopyClasspath := false`.
Otherwise the needed jars were deleted before the hooks could run.
Bonus: delete unused ResourceLoaderImpl class
Ethan Atkins
Eugene Yokota
Ignasi Marimon-Clos
Eric Peters
Josh Soref