public JsStatement VisitGotoStateStatement(JsGotoStateStatement statement, object data)
{
var result = new List <JsStatement>();
State targetState;
if (statement.TargetState == null)
{
if (!_labelStates.TryGetValue(statement.TargetLabel, out targetState))
{
throw new InvalidOperationException("The label " + statement.TargetLabel + " does not exist.");
}
}
else
{
targetState = statement.TargetState.Value;
}
var remaining = statement.CurrentState.FinallyStack;
for (int i = 0, n = remaining.Count() - targetState.FinallyStack.Count(); i < n; i++)
{
var current = remaining.Peek();
remaining = remaining.Pop();
result.Add(JsExpression.Assign(JsExpression.Identifier(_stateVariableName), JsExpression.Number(remaining.IsEmpty ? -1 : remaining.Peek().Item1)));
result.Add(JsExpression.Invocation(JsExpression.Member(JsExpression.Identifier(current.Item2), "call"), JsExpression.This));
}
result.Add(MakeSetNextStateStatement(targetState.StateValue));
result.Add(targetState.StateValue == -1 ? (JsStatement)JsStatement.Break(targetState.LoopLabelName) : JsStatement.Continue(targetState.LoopLabelName));
return(JsStatement.BlockMerged(result));
}
public override JsStatement VisitVariableDeclarationStatement(JsVariableDeclarationStatement statement, object data)
{
List <JsExpression> list = null;
foreach (var d in statement.Declarations)
{
_variables.Add(d.Name);
if (d.Initializer != null)
{
list = list ?? new List <JsExpression>();
list.Add(JsExpression.Assign(JsExpression.Identifier(d.Name), d.Initializer));
}
}
if (list == null)
{
return(JsStatement.BlockMerged(new JsStatement[0]));
}
else if (list.Count == 1)
{
return(list[0]);
}
else
{
return(JsExpression.Comma(list));
}
}
public override JsStatement VisitReturnStatement(JsReturnStatement statement, object data)
{
if (_makeSetResult != null)
{
return(JsStatement.BlockMerged(_makeSetResult(statement.Value), JsStatement.Return()));
}
else
{
return(statement);
}
}
private bool HandleTryStatement(JsTryStatement stmt, StackEntry location, ImmutableStack <StackEntry> stack, ImmutableStack <Tuple <string, State> > breakStack, ImmutableStack <Tuple <string, State> > continueStack, State currentState, State returnState, IList <JsStatement> currentBlock, bool isFirstStatement)
{
if (_isIteratorBlock && (FindInterestingConstructsVisitor.Analyze(stmt.GuardedStatement, InterestingConstruct.YieldReturn) || (stmt.Finally != null && stmt.Catch == null && !currentState.FinallyStack.IsEmpty)))
{
if (stmt.Catch != null)
{
throw new InvalidOperationException("Cannot yield return from try with catch");
}
string handlerName = _allocateFinallyHandler();
JsBlockStatement handler;
if (FindInterestingConstructsVisitor.Analyze(stmt.Finally, InterestingConstruct.Label))
{
var inner = ProcessInner(stmt.Finally, breakStack, continueStack, currentState.FinallyStack, currentState.StateValue);
handler = JsStatement.Block(new[] { new JsSetNextStateStatement(inner.Item2) }.Concat(inner.Item1));
handler = new FinalizerRewriter(_stateVariableName, _labelStates).Process(handler);
}
else
{
handler = stmt.Finally;
}
_finallyHandlers.Add(Tuple.Create(handlerName, handler));
var stateAfter = GetStateAfterStatement(location, stack, currentState.FinallyStack, returnState);
var innerState = CreateNewStateValue(currentState.FinallyStack, handlerName);
var stateBeforeFinally = CreateNewStateValue(innerState.FinallyStack);
currentBlock.Add(new JsSetNextStateStatement(innerState.StateValue));
currentBlock.AddRange(Handle(ImmutableStack <StackEntry> .Empty.Push(new StackEntry(stmt.GuardedStatement, 0)), breakStack, continueStack, new State(currentState.LoopLabelName, currentState.StateValue, innerState.FinallyStack), stateBeforeFinally, false, false));
Enqueue(ImmutableStack <StackEntry> .Empty.Push(new StackEntry(JsStatement.Block(JsStatement.BlockMerged(new JsStatement[0])), 0)), breakStack, continueStack, stateBeforeFinally, stateAfter.Item1);
if (!stack.IsEmpty || location.Index < location.Block.Statements.Count - 1)
{
Enqueue(PushFollowing(stack, location), breakStack, continueStack, stateAfter.Item1, returnState);
}
return(false);
}
else if (_isIteratorBlock && stmt.Finally != null && !currentState.FinallyStack.IsEmpty)
{
// This is necessary to special-case in order to ensure that the inner finally block is executed before all outer ones.
return(HandleTryStatement(JsStatement.Try(JsStatement.Try(stmt.GuardedStatement, stmt.Catch, null), null, stmt.Finally), location, stack, breakStack, continueStack, currentState, returnState, currentBlock, isFirstStatement));
}
else
{
var rewriter = new NestedStatementFixer(breakStack, continueStack, currentState, _exitState.Value, _makeSetResult);
JsBlockStatement guarded;
var guardedConstructs = FindInterestingConstructsVisitor.Analyze(stmt.GuardedStatement);
if ((guardedConstructs & (InterestingConstruct.Label | InterestingConstruct.Await)) != InterestingConstruct.None)
{
if (!isFirstStatement)
{
var sv = CreateNewStateValue(currentState.FinallyStack);
Enqueue(stack.Push(location), breakStack, continueStack, sv, returnState);
currentBlock.Add(new JsGotoStateStatement(sv, currentState));
return(false);
}
var inner = ProcessInner(stmt.GuardedStatement, breakStack, continueStack, currentState.FinallyStack, currentState.StateValue);
guarded = JsStatement.Block(inner.Item1);
currentBlock.Add(new JsSetNextStateStatement(inner.Item2));
}
else
{
guarded = rewriter.Process(stmt.GuardedStatement);
}
JsCatchClause @catch;
if (stmt.Catch != null)
{
if (FindInterestingConstructsVisitor.Analyze(stmt.Catch.Body, InterestingConstruct.Label))
{
var inner = ProcessInner(stmt.Catch.Body, breakStack, continueStack, currentState.FinallyStack, null);
@catch = JsStatement.Catch(stmt.Catch.Identifier, JsStatement.Block(new[] { new JsSetNextStateStatement(inner.Item2) }.Concat(inner.Item1)));
}
else
{
var body = rewriter.Process(stmt.Catch.Body);
@catch = ReferenceEquals(body, stmt.Catch.Body) ? stmt.Catch : JsStatement.Catch(stmt.Catch.Identifier, body);
}
}
else
{
@catch = null;
}
JsBlockStatement @finally;
if (stmt.Finally != null)
{
if (FindInterestingConstructsVisitor.Analyze(stmt.Finally, InterestingConstruct.Label))
{
var inner = ProcessInner(stmt.Finally, breakStack, continueStack, currentState.FinallyStack, null);
@finally = JsStatement.Block(new[] { new JsSetNextStateStatement(inner.Item2) }.Concat(inner.Item1));
}
else
{
@finally = rewriter.Process(stmt.Finally);
}
if ((guardedConstructs & InterestingConstruct.Await) != InterestingConstruct.None)
{
// Wrap the finally block inside an 'if (doFinallyBlocks) {}'
@finally = JsStatement.Block(JsStatement.If(JsExpression.Identifier(_doFinallyBlocksVariableName), @finally, null));
}
}
else
{
@finally = null;
}
if (currentBlock.Count > 0 && _childStates.ContainsKey(currentState.StateValue))
{
var newBlock = JsStatement.If(JsExpression.Same(JsExpression.Identifier(_stateVariableName), JsExpression.Number(currentState.StateValue)), JsStatement.Block(currentBlock), null);
currentBlock.Clear();
currentBlock.Add(newBlock);
}
currentBlock.Add(JsStatement.Try(guarded, @catch, @finally));
return(true);
}
}
private bool HandleAwaitStatement(JsAwaitStatement stmt, StackEntry location, ImmutableStack <StackEntry> stack, ImmutableStack <Tuple <string, State> > breakStack, ImmutableStack <Tuple <string, State> > continueStack, State currentState, State returnState, IList <JsStatement> currentBlock)
{
var stateAfter = GetStateAfterStatement(location, stack, currentState.FinallyStack, returnState).Item1;
bool createDummyState = false;
if (stateAfter.StateValue == returnState.StateValue)
{
stateAfter = CreateNewStateValue(currentState.FinallyStack);
createDummyState = true; // We must never return to our parent state after an await because
}
currentBlock.Add(new JsSetNextStateStatement(stateAfter.StateValue));
currentBlock.Add(JsExpression.Invocation(JsExpression.Member(stmt.Awaiter, stmt.OnCompletedMethodName), JsExpression.Identifier(_stateMachineMethodName)));
if (_needDoFinallyBlocksVariable)
{
currentBlock.Add(JsExpression.Assign(JsExpression.Identifier(_doFinallyBlocksVariableName), JsExpression.False));
}
currentBlock.Add(JsStatement.Return());
if (!stack.IsEmpty || location.Index < location.Block.Statements.Count - 1)
{
Enqueue(PushFollowing(stack, location), breakStack, continueStack, stateAfter, returnState);
}
if (createDummyState)
{
Enqueue(ImmutableStack <StackEntry> .Empty.Push(new StackEntry(JsStatement.Block(JsStatement.BlockMerged(new JsStatement[0])), 0)), breakStack, continueStack, stateAfter, returnState);
}
return(false);
}
public virtual JsStatement VisitBlockStatement(JsBlockStatement statement, TData data)
{
var after = VisitStatements(statement.Statements, data);
return(ReferenceEquals(after, statement.Statements) ? statement : (statement.MergeWithParent ? JsStatement.BlockMerged(after) : JsStatement.Block(after)));
}