public static bool Analyze(JsStatement statement)
{
var obj = new UsesThisVisitor();
obj.VisitStatement(statement, null);
return(obj._result);
}
public static bool Analyze(JsExpression expression)
{
var obj = new UsesThisVisitor();
obj.VisitExpression(expression, null);
return(obj._result);
}
private JsBlockStatement ProcessAsyncMethod(JsBlockStatement statement, string stateMachineMethodName, string doFinallyBlocksVariableName, JsVariableDeclaration taskCompletionSource, Func <JsExpression, JsExpression> makeSetResult, Func <JsExpression, JsExpression> makeSetException, Func <JsExpression> getTask, Func <JsExpression, JsExpression, JsExpression> bindToContext)
{
_stateMachineMethodName = stateMachineMethodName;
_doFinallyBlocksVariableName = doFinallyBlocksVariableName;
_makeSetResult = taskCompletionSource != null ? makeSetResult : null;
_needDoFinallyBlocksVariable = new HasAwaitInsideTryWithFinallyVisitor().Analyze(statement);
var result = Process(statement, isIteratorBlock: false, isAsync: true);
var hoistResult = VariableHoistingVisitor.Process(result);
string catchVariable = _allocateTempVariable();
JsStatement body;
if (taskCompletionSource != null && (statement.Statements.Count == 0 || IsNextStatementReachable(statement.Statements[statement.Statements.Count - 1]))) // If we return the task, and if we risk falling out of the original method, we need to add a setResult call.
{
body = JsStatement.Block(hoistResult.Item1.Statements.Concat(new JsStatement[] { makeSetResult(null) }));
}
else
{
body = hoistResult.Item1;
}
if (taskCompletionSource != null)
{
body = JsStatement.Try(body, JsStatement.Catch(catchVariable, JsStatement.Block(makeSetException(JsExpression.Identifier(catchVariable)))), null);
}
IEnumerable <JsVariableDeclaration> declarations = new[] { JsStatement.Declaration(_stateVariableName, JsExpression.Number(0)) };
if (taskCompletionSource != null)
{
declarations = declarations.Concat(new[] { taskCompletionSource });
}
declarations = declarations.Concat(hoistResult.Item2.Select(v => JsStatement.Declaration(v, null)));
if (_needDoFinallyBlocksVariable)
{
body = JsStatement.Block(new[] { JsStatement.Var(_doFinallyBlocksVariableName, JsExpression.True) }.Concat(body is JsBlockStatement ? ((JsBlockStatement)body).Statements : (IEnumerable <JsStatement>) new[] { body }));
}
var stateMachine = JsExpression.FunctionDefinition(new string[0], body);
var boundStateMachine = UsesThisVisitor.Analyze(stateMachine.Body) ? bindToContext(stateMachine, JsExpression.This) : stateMachine;
IEnumerable <JsStatement> stmts = new JsStatement[] { JsStatement.Var(declarations),
JsStatement.Var(stateMachineMethodName, boundStateMachine),
JsExpression.Invocation(JsExpression.Identifier(stateMachineMethodName)) };
if (taskCompletionSource != null)
{
stmts = stmts.Concat(new[] { JsStatement.Return(getTask()) });
}
return(JsStatement.Block(stmts));
}