1) non-default derived settings, if they produce anything, the settings
they produce must supersede previous assignents (in the settings seq)
to the same key.
2) even if a derived setting is scoped at a higher scope (e.g.
ThisBuild) the settings it produces are scoped at the intersection of
that (the defining) scope and the scope of the triggering dependency.
2 is particularly nice as it enables this behaviour:
derive(b in ThisBuild := a.value + 1)
a in project1 := 0
// a could be defined in all projects
==>
Now (b in project1).value == (a in project1).value + 1 == 1
and similarly in all other projects
all with a single derived setting
* Create a new EvaluateTaskConfig which gives us a bit more freedom
over changign config options to EvaluateTask in the future.
* Create adapted from old EvaluateTask to new EvaluateTask
* Add hooks into signals class to register/remote a signal listener
directly, rather than in an "arm" block.
* Create TaskEvaluationCancelHandler to control the strategy of
who/whom can cancel (sbt-server vs. sbt-terminal).
* Create a null-object for the "can't cancel" scenario so the
code path is exactly the same.
This commit does not wire settings into the build yet, nor does it
fix the config extractio methods.
We shouldn't assume that the qualifier of a `Select` is a
`SymTree`; it may be a `Block`. One place that happens
is after the transformation of named/defaults applications.
That causes the reported `NullPointerException'.
In any case, using `qual.symbol.pos` sense here; it yields the
position of the defintions *referred to* by `qual`, not the
position of `qual` itself.
Both problems are easily fixed: use `qual.pos` instead.
Fixes#1107
The qualifier of the `.value` call may contain `DefTree`s (e.g.
vals, defs) or `Function` trees. When we snip them out of the
tree and graft them into a new context, we must also call
`changeOwner`, so that the symbol owner structure and the tree
structure are coherent.
Failure to do so resulted in a crash in the compiler backend.
Fixes#1150
The qualifier of the `.value` call may contain `DefTree`s (e.g.
vals, defs) or `Function` trees. When we snip them out of the
tree and graft them into a new context, we must also call
`changeOwner`, so that the symbol owner structure and the tree
structure are coherent.
Failure to do so resulted in a crash in the compiler backend.
Fixes#1150
This commit makes the code source compatible across Scala 2.10.3
and https://github.com/scala/scala/pull/3452, which is proposed
for inclusion in Scala 2.11.0-RC1.
We only strictly need the incremental compiler to build on Scala
2.11, as that is integrated into the IDE. But we gain valuable
insight into compiler regressions by building *all* of SBT with
2.11.
We only got there recently (the 0.13 branch of SBT now fully cross
compiles with 2.10.3 and 2.11.0-SNAPSHOT), and this aims to keep
things that way.
Once 2.10 support is dropped, SBT macros will be able to exploit
the new reflection APIs in 2.11 to avoid the need for casting
to compiler internals, which aren't governed by binary compatibility.
This has been prototyped by @xeno-by: https://github.com/sbt/sbt/pull/1121
Since the fix for SI-2066, Scala 2.11 calls logicallyEnclosingMember on the
`x` in the expansion of the task macro:
InitializeInstance.app[[T0[x]](T0[java.io.File], T0[java.io.File]), Seq[java.io.File]]
This exposed the fact that SBT has created `T0` with `NoSymbol` as
the owner. This led to the a SOE.
I will also change the compiler to be more tolerant of this, but we
can observe good discipline in the macro and pick a sensible owner.
Still TODO for auto-plugins/logic:
* property-based tests for logic system
* user documentation
* (optional) 'about plugins' or similar to show more information about the auto-plugins for a project
* (deferred) allow AutoPlugin to inject Commands directly?
* (deferred) provide AutoPlugin functionality to arbitrary scopes instead of just at the Project level?
This requires a Format[T] to be implicitly available at the call site and requires the task
to be referenced statically (not in a settingDyn call). References to previous task values
in the form of a ScopedKey[Task[T]] + Format[T] are collected at setting load time in the
'references' setting. These are used to know which tasks should be persisted (the ScopedKey)
and how to persist them (the Format).
When checking/delegating previous references, rules are slightly different.
A normal reference from a task t in scope s cannot refer to t in s unless
there is an earlier definition of t in s. However, a previous reference
does not have this restriction. This commit modifies validateReferenced
to allow this.
TODO: user documentation
TODO: stable selection of the Format when there are multiple .previous calls on the same task
TODO: make it usable in InputTasks, specifically Parsers
The fix was made possible by the very helpful information provided by @retronym.
This commit does two key things:
1. changes the owner when splicing original trees into new trees
2. ensures the synthetic trees that get spliced into original trees do not need typechecking
Given this original source (from Defaults.scala):
...
lazy val sourceConfigPaths = Seq(
...
unmanagedSourceDirectories := Seq(scalaSource.value, javaSource.value),
...
)
...
After expansion of .value, this looks something like:
unmanagedSourceDirectories := Seq(
InputWrapper.wrapInit[File](scalaSource),
InputWrapper.wrapInit[File](javaSource)
)
where wrapInit is something like:
def wrapInit[T](a: Any): T
After expansion of := we have (approximately):
unmanagedSourceDirectories <<=
Instance.app( (scalaSource, javaSource) ) {
$p1: (File, File) =>
val $q4: File = $p1._1
val $q3: File = $p1._2
Seq($q3, $q4)
}
So,
a) `scalaSource` and `javaSource` are user trees that are spliced into a tuple constructor after being temporarily held in `InputWrapper.wrapInit`
b) the constructed tuple `(scalaSource, javaSource)` is passed as an argument to another method call (without going through a val or anything) and shouldn't need owner changing
c) the synthetic vals $q3 and $q4 need their owner properly set to the anonymous function
d) the references (Idents) $q3 and $q4 are spliced into the user tree `Seq(..., ...)` and their symbols need to be the Symbol for the referenced vals
e) generally, treeCopy needs to be used when substituting Trees in order to preserve attributes, like Types and Positions
changeOwner is called on the body `Seq($q3, $q4)` with the original owner sourceConfigPaths to be changed to the new anonymous function.
In this example, no owners are actually changed, but when the body contains vals or anonymous functions, they will.
An example of the compiler crash seen when the symbol of the references is not that of the vals:
symbol value $q3 does not exist in sbt.Defaults.sourceConfigPaths$lzycompute
at scala.reflect.internal.SymbolTable.abort(SymbolTable.scala:49)
at scala.tools.nsc.Global.abort(Global.scala:254)
at scala.tools.nsc.backend.icode.GenICode$ICodePhase.genLoadIdent$1(GenICode.scala:1038)
at scala.tools.nsc.backend.icode.GenICode$ICodePhase.scala$tools$nsc$backend$icode$GenICode$ICodePhase$$genLoad(GenICode.scala:1044)
at scala.tools.nsc.backend.icode.GenICode$ICodePhase$$anonfun$genLoadArguments$1.apply(GenICode.scala:1246)
at scala.tools.nsc.backend.icode.GenICode$ICodePhase$$anonfun$genLoadArguments$1.apply(GenICode.scala:1244)
...
Other problems with the synthetic tree when it is spliced under the original tree often result in type mismatches or some other compiler error that doesn't result in a crash.
If the owner is not changed correctly on the original tree that gets spliced under a synthetic tree, one way it can crash the compiler is:
java.lang.IllegalArgumentException: Could not find proxy for val $q23: java.io.File in List(value $q23, method apply, anonymous class $anonfun$globalCore$5, value globalCore, object Defaults, package sbt, package <root>) (currentOwner= value dir )
...
while compiling: /home/mark/code/sbt/main/src/main/scala/sbt/Defaults.scala
during phase: global=lambdalift, atPhase=constructors
...
last tree to typer: term $outer
symbol: value $outer (flags: <synthetic> <paramaccessor> <triedcooking> private[this])
symbol definition: private[this] val $outer: sbt.BuildCommon
tpe: <notype>
symbol owners: value $outer -> anonymous class $anonfun$87 -> value x$298 -> method derive -> class BuildCommon$class -> package sbt
context owners: value dir -> value globalCore -> object Defaults -> package sbt
...
The problem here is the difference between context owners and the proxy search chain.
Eugene Yokota
Dan Sanduleac
Dan Sanduleac
Matej Urbas
Josh Suereth
Jason Zaugg
Mark Harrah
Benjy
Bruno Bieth