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SI-6829, SI-6788, NPEs during erroneous compilation.

Have to intercept trees which have a null type due to errors
before they leave the warm confines of 'def typed' because from
that point everything assumes tree.tpe != null.
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1 parent 5666468 commit 231d59dcf57af99a9e2a1366afd18680c13cd6ce @paulp paulp committed Dec 22, 2012
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12 src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -5264,7 +5264,7 @@ trait Typers extends Modes with Adaptations with Tags {
def typedDocDef(docdef: DocDef) = {
if (forScaladoc && (sym ne null) && (sym ne NoSymbol)) {
- val comment = docdef.comment
+ val comment = docdef.comment
docComments(sym) = comment
comment.defineVariables(sym)
val typer1 = newTyper(context.makeNewScope(tree, context.owner))
@@ -5595,12 +5595,18 @@ trait Typers extends Modes with Adaptations with Tags {
"context.owner" -> context.owner
)
)
- val tree1 = typed1(tree, mode, dropExistential(pt))
+ typed1(tree, mode, dropExistential(pt))
+ }
+ // Can happen during erroneous compilation - error(s) have been
+ // reported, but we need to avoid causing an NPE with this tree
+ if (tree1.tpe eq null)
+ return setError(tree)
+
+ if (!alreadyTyped) {
printTyping("typed %s: %s%s".format(
ptTree(tree1), tree1.tpe,
if (isSingleType(tree1.tpe)) " with underlying "+tree1.tpe.widen else "")
)
- tree1
}
tree1.tpe = addAnnotations(tree1, tree1.tpe)
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5 test/files/neg/t6788.check
@@ -0,0 +1,5 @@
+t6788.scala:6: error: not found: value foo
+Error occurred in an application involving default arguments.
+ s.copy(b = foo)
+ ^
+one error found
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7 test/files/neg/t6788.scala
@@ -0,0 +1,7 @@
+case class B[T](b: T, a: List[Int]) // need two args, B must be polymorphic
+
+class A {
+ var s: B[Int] = _ // has to be a var
+
+ s.copy(b = foo)
+}
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36 test/files/neg/t6829.check
@@ -0,0 +1,36 @@
+t6829.scala:35: error: type mismatch;
+ found : AgentSimulation.this.state.type (with underlying type G#State)
+ required: _10.State
+ lazy val actions: Map[G#Agent,G#Action] = agents.map(a => a -> a.chooseAction(state)).toMap
+ ^
+t6829.scala:45: error: trait AgentSimulation takes type parameters
+ pastHistory: List[G#State] = Nil) extends AgentSimulation
+ ^
+t6829.scala:47: error: class LearningSimulation takes type parameters
+ lazy val step: LearningSimulation = {
+ ^
+t6829.scala:49: error: not found: value actions
+ val (s,a,s2) = (state,actions(agent),nextState)
+ ^
+t6829.scala:49: error: not found: value nextState
+ val (s,a,s2) = (state,actions(agent),nextState)
+ ^
+t6829.scala:50: error: type mismatch;
+ found : s.type (with underlying type Any)
+ required: _54.State where val _54: G
+ val r = rewards(agent).r(s,a,s2)
+ ^
+t6829.scala:51: error: type mismatch;
+ found : s.type (with underlying type Any)
+ required: _51.State
+ agent.learn(s,a,s2,r): G#Agent
+ ^
+t6829.scala:53: error: not found: value nextState
+Error occurred in an application involving default arguments.
+ copy(agents = updatedAgents, state = nextState, pastHistory = currentHistory)
+ ^
+t6829.scala:53: error: not found: value currentHistory
+Error occurred in an application involving default arguments.
+ copy(agents = updatedAgents, state = nextState, pastHistory = currentHistory)
+ ^
+9 errors found
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64 test/files/neg/t6829.scala
@@ -0,0 +1,64 @@
+package bugs
+
+/**
+ * Created with IntelliJ IDEA.
+ * User: arya
+ * Date: 12/18/12
+ * Time: 4:17 PM
+ * To change this template use File | Settings | File Templates.
+ */
+object currenttype2 {
+
+ type Reward = Double
+
+ trait AbstractAgent[State,Action] {
+ type A = AbstractAgent[State,Action]
+ def chooseAction(s: State): Action
+ def startEpisode: A = this
+ def learn(s1: State, a: Action, s2: State, r: Reward): A
+ }
+
+ case class RewardFunction[State,Action](r: (State,Action,State) => Reward)
+
+ trait Rules[G<:GameDomain] {
+ def simulate(state: G#State, agentActions: List[(G#Agent,G#Action)]): G#State
+ }
+
+ trait AgentSimulation[G<:GameDomain] {
+ val agents: List[G#Agent]
+ val state: G#State
+ val rewards: Map[G#Agent,G#Rewards]
+ val rules: Rules[G]
+ val pastHistory: List[G#State]
+ lazy val currentHistory = state :: pastHistory
+
+ lazy val actions: Map[G#Agent,G#Action] = agents.map(a => a -> a.chooseAction(state)).toMap
+ lazy val nextState: G#State = rules.simulate(state, actions.toList)
+
+ def step: AgentSimulation[G]
+ }
+
+ case class LearningSimulation[G<:GameDomain](agents: List[G#Agent],
+ state: G#State,
+ rewards: Map[G#Agent,G#Rewards],
+ rules: Rules[G],
+ pastHistory: List[G#State] = Nil) extends AgentSimulation
+ {
+ lazy val step: LearningSimulation = {
+ val updatedAgents: List[G#Agent] = agents map { agent =>
+ val (s,a,s2) = (state,actions(agent),nextState)
+ val r = rewards(agent).r(s,a,s2)
+ agent.learn(s,a,s2,r): G#Agent
+ }
+ copy(agents = updatedAgents, state = nextState, pastHistory = currentHistory)
+ }
+ }
+
+ trait GameDomain {
+ domain =>
+ type State
+ type Action
+ type Agent = AbstractAgent[State, Action] // agent supertype
+ type Rewards = RewardFunction[State,Action]
+ }
+ }

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