Changed resources were causing the dependency layer to be invalidated on
resource changes in turbo mode because the resource layer was in between
the scala library layer. This commit reworks the layers for the
AllDependencyJars strategy so that the top layer is able to load _all_
of the resources during a test run.
The resource layer was added to address the problem that dependencies
may need to be able to load resources from the project classpath but
wouldn't be able to do so if the dependencies were in a separate layer
from the rest of the classpath. The resource layer was a classloader
that could load any resource on the full classpath but couldn't load any
classes. When I added the resource layer, I was thinking that when
resources changed, the resource class loader needed to be invalidated.
Resources, however, are different from classes in that the same
ClassLoader can find the same resources in a different place because
getResource and getResourceAsStream just return locations but do not
actually do any loading.
Taking advantage of this, I add a proxy classloader for finding
resource locations to ReverseLookupClassLoader. We can reset the
classpath of the resource loader in
ReverseLookupClassLoaderHolder.checkout. This allows us to see the new
versions of the resources without invalidating the dependency layer.
Sometimes turbo mode didn't work correctly for projects where resources
were modified. This was because it was possible for the resource
classloader to inadvertently evict the dependency classloader from the
classloader cache because they had the same file stamps. There were two
fixes:
1) remove expired entries from the cache based on the
(Parent, Classpath) pair rather than just classpath
2) do not close the classloaders during cache eviction. They may still
be in use when we evict them so we need to wait until they are
explicitly closed elsewhere or until the go out of scope and are
collected by the CleanupThread
I tested this change with a spark project in which I kept modifying the
resources. Prior to this change, I could get into a state where if I
modified the resources, the dependency layer would get evicted every
time so the benefits of turbo mode were not realized.
There have been numerous issues with the multi parser incorrectly
splitting commands like `alias foo = ; bar` into
`"alias foo =" :: "bar" :: Nil`. To fix this, I update the multi parser
implementation to accept a list of commands that cannot be part of a
multi command. For now, the only excluded command is "alias", but if
other issues come up, we can add more. I also thought about adding a
system property for excluding more commands but it didn't seem worth the
maintenance cost at this point.
In addition to adding a filter for the excluded commands, I also
reworked the multi parser so that I think its more clear (and should
hopefully have more predictable performance). I changed the cmdPart
parser to accept empty strings. Prior to this, the parser explicitly
handled the non-leading semicolon and leading semicolon cases
separately. With the relaxed cmdPart, we can handle both cases with a
single parser. We just have to strip any empty commands at the beginning
or end of the command list.
It was reported in https://github.com/sbt/sbt/issues/4890 that cosmetic
white space could cause problems for the paser. I tracked this down to
primarily being because of the
`val semi = token(OptSpace ~> ';' ~> OptSpace)` line. This would cause
excessive backtracking. I added a test for a multi line command with a
lot of cosmetic whitespace that was adapted from #4890 except that I
made it even more taxing by running adding 100 commands instead of the
roughly 10 in the report. Before the parser changes, the test would
more or less block indefinitely. I never saw it successfully complete.
After these changes, it completes in 30-50ms (which drops to about 2-3
ms if the number of commands is dropped from 100 to 3).
I verified manually in a different project that a number of different
multi command completions still worked. In particular, I tested that
`~foo/test; foo/tes` would expand to `~foo/test; foo/test` which is one
of the hardest cases to get right.
I also added a few extra test cases for the parser since I wasn't sure
what the impact of removing the OptSpace ~> from the semi parser would
be.
The use of '$' in the path names for streams is a pain because, since
'$' is a special character in the shell, it makes it impossible to
directly copy and paste the paths. If we make this change, some builds
will be left with vestigial directories with $global and $build in them
until they run clean. It also would break any scripts that manually
delete these paths. That doesn't seem like a common use case, but it's
worth mentioning.
Fixes#4889#4329 switched from using Map to Seq during packaging. That allowed multiple files to be included with different paths, but it also started admitting duplicate files causing ZipException.
We tried to prevent users from doing something like running a multi
command "foo; bar" where foo is valid but bar is invalid so that we
wouldn't run foo only to discover bar was an invalid key. It isn't
possible to know in general if any command other than the first command
in a multi command is valid because it might update the state and add
the initially invalid command.
The validation caused the intellij plugin to not work with 1.3.0-RC3.
This scripted tests failed on the linux travis ci build with an
error around relocation. It said to use -fPIC in the compilation so
that's what I'm doing. It also said I needed to set the -std=c99 flag.
It was reported in #4868 that exclueFilters didn't work correctly if
there was an || in the filter. This was an upstream issue in io, but
this commit adds a scripted test in sbt.
The recent changes to make the multi parser strict broke any multi
command, or alias, where the multi command contained a command or task
that was not yet defined, but was possibly added by reload. This was
reported as #4869. I had had to work around this issue in ScriptedTests
by running `reload` and `setUpScripted` separately instead of as a multi
command. This workaround doesn't work for aliasing boot, which has been
a recommended approach by Mark Harrah since 2011.
To fix this, I relax the strict parser. We don't require that the parser
be valid to create a multi command string. In the multiApplied state
transformation, however, we validate all of the commands up to 'reload'.
Since there is no way to validate any commands to the right of 'reload,
we optimistically allow those commands to run.
So long as there is no 'reload' in the multi commands, all of the
commands will be validated.
The use of the persistent file stamp cache between watch runs didn't
seem to cause any issues, but there was some chance for inconsistency
between the file stamp cache and the file system so it makes sense to
put it behind the turbo flag.
After changing the default, the watch/on-change scripted test started
failing. It turns out that the reason is that the file stamp cache
managed by the watch process was not pre-filled by task evaluation. For
this reason, the first time a source file was modified, it was treated
as a creation regardless of whether or not it actually was.
To fix this, I add logic to pre-fill the watch file stamp cache if we
are _not_ persisting the file stamps between runs.
I ran a before and after with the scala build performance benchmark tool
and setting the watchPersistFileStamps key to true reduced the median
run time by about 200ms in the non-turbo case.
There was a bug where sometimes a source file change would not trigger a
new build if the change occurred during a build. Based on the logs, it
seemed to be because a number of redundant events were generated for the
same path and they triggered the anti-entropy constraint of the file
event monitor.
To fix this, I consolidated a number of observers of the global file
tree repository into a single observer. This way, I am able to ensure
that only one event is generated per file event.
I also reworked the onEvent callback to only stamp the file once. It was
previously stamping the modified source file for all of the aggregated
tasks. In the sbt project running `~compile` meant that we were stamping
a source file 22 times whenever the file changed.
This actually uncovered a zinc issue though as well. Zinc computes and
writes the hash of the source file to the analysis file after
compilation has completed. If a source file is modified during
compilation, then the new hash is written to the analysis file even when
the compilation may have been made against the previous version of the
file. Zinc will then refuse to re-compile that file until another change
is made.
I manually verified that in the sbt project if I ran `~compile` before
this change and modified a file during compilation, then no event was
triggered (there was a log message about the event being dropped due to
the anti-entropy constraint though). After this change, if I changed a
file during compilation, it seemed to always trigger, but due to the
zinc bug, it didn't always re-compile.
This was causing an abstract type pattern T is unchecked since it is
eliminated by erasure. It was unneeded because store.get[T] return
Option[(T, Long)]. I'm surprised that the compiler complained about
this.
@olegych reported that sbt would silently swallow the 'compile' command
in the multi-command, 'run;compile;reload'. I tracked this down to the
build source check. When the build has
Global / onChangedBuildSource := ReloadOnSourceChanges, the check build
sources command return a new state with "reload" prefixed. To actually
perform the reload, I returned this modified state with the prefixed
reload command.
There were two problems with this:
1) In the auto-reload case, the current command was not run after the
reload
2) If the multi-command contained reload, the auto-reload check would
have a false positive which triggered the bug in (1)
To fix this, I clear out the remaining commands before I run the check
command. That way, we know that if the remaining commands has a reload,
then it is an auto-reload. We then prefix the state with both the reload
and the current command.
I updated the scripted test for auto-reload to handle multi commands
containing reload.
Ethan Atkins
eugene yokota
Johannes Rudolph
Nafer Sanabria
kenji yoshida