public bool HandleFor(ForStatement node)
{
var iterable = Eval.GetValueFromExpression(node.List);
var iterator = (iterable as IPythonIterable)?.GetIterator();
var value = iterator?.Next ?? Eval.UnknownType;
switch (node.Left)
{
case NameExpression nex:
// for x in y:
if (!string.IsNullOrEmpty(nex.Name))
{
Eval.DeclareVariable(nex.Name, value, VariableSource.Declaration, nex);
}
break;
case SequenceExpression seq:
// x = [('abc', 42, True), ('abc', 23, False)]
// for some_str, (some_int, some_bool) in x:
var h = new SequenceExpressionHandler(Walker);
h.HandleAssignment(seq, value);
break;
}
node.Body?.Walk(Walker);
node.Else?.Walk(Walker);
return(false);
}
public void HandleWith(WithStatement node)
{
foreach (var item in node.Items.Where(x => x.Variable != null))
{
var contextManager = Eval.GetValueFromExpression(item.ContextManager);
var cmType = contextManager?.GetPythonType();
IMember context = Eval.UnknownType;
var enter = cmType?.GetMember(node.IsAsync ? @"__aenter__" : @"__enter__")?.GetPythonType <IPythonFunctionType>();
if (enter != null)
{
var instance = contextManager as IPythonInstance;
var callExpr = item.ContextManager as CallExpression;
context = Eval.GetValueFromFunctionType(enter, instance, callExpr);
// If fetching context from __enter__ failed, annotation in the stub may be using
// type from typing that we haven't specialized yet or there may be an issue in
// the stub itself, such as type or incorrect type. Try using context manager then.
context = context.IsUnknown() ? contextManager : context;
}
switch (item.Variable)
{
case NameExpression nameExpr when !string.IsNullOrEmpty(nameExpr.Name):
Eval.DeclareVariable(nameExpr.Name, context, VariableSource.Declaration, item);
break;
case ParenthesisExpression parExpr:
case SequenceExpression seqExpr:
var sequenceHandler = new SequenceExpressionHandler(Walker);
SequenceExpressionHandler.Assign(new[] { item.Variable }, context, Eval);
break;
}
}
}
public void HandleAssignment(AssignmentStatement node)
{
if (node.Right is ErrorExpression)
{
return;
}
var value = Eval.GetValueFromExpression(node.Right) ?? Eval.UnknownType;
// Filter out parenthesis expression in assignment because it makes no difference.
var lhs = node.Left.Select(s => s.RemoveParenthesis());
// Check PEP hint first
var valueType = Eval.GetTypeFromPepHint(node.Right);
if (valueType != null)
{
HandleTypedVariable(valueType, value, lhs.FirstOrDefault());
return;
}
if (value.IsUnknown())
{
Log?.Log(TraceEventType.Verbose, $"Undefined value: {node.Right.ToCodeString(Ast).Trim()}");
}
if (value?.GetPythonType().TypeId == BuiltinTypeId.Ellipsis)
{
value = Eval.UnknownType;
}
foreach (var expr in lhs)
{
switch (expr)
{
case SequenceExpression seq:
// Tuple = Tuple. Transfer values.
var seqHandler = new SequenceExpressionHandler(Walker);
seqHandler.HandleAssignment(seq, value);
break;
case ExpressionWithAnnotation annExpr:
HandleAnnotatedExpression(annExpr, value);
break;
case NameExpression nameExpr:
HandleNameExpression(nameExpr, value);
break;
case MemberExpression memberExpr:
TryHandleClassVariable(memberExpr, value);
break;
}
}
}
private void AssignToExpr(Expression expr, IMember value)
{
switch (expr)
{
case SequenceExpression seq:
// Tuple = Tuple. Transfer values.
var seqHandler = new SequenceExpressionHandler(Walker);
seqHandler.HandleAssignment(seq, value);
break;
case ExpressionWithAnnotation annExpr:
HandleAnnotatedExpression(annExpr, value);
break;
case NameExpression nameExpr:
HandleNameExpression(nameExpr, value);
break;
case MemberExpression memberExpr:
TryHandleClassVariable(memberExpr, value);
break;
}
}
public void HandleAssignment(AssignmentStatement node)
{
if (node.Right is ErrorExpression)
{
return;
}
var value = Eval.GetValueFromExpression(node.Right) ?? Eval.UnknownType;
// Check PEP hint first
var valueType = Eval.GetTypeFromPepHint(node.Right);
if (valueType != null)
{
HandleTypedVariable(valueType, value, node.Left.FirstOrDefault());
return;
}
if (value.IsUnknown())
{
Log?.Log(TraceEventType.Verbose, $"Undefined value: {node.Right.ToCodeString(Ast).Trim()}");
}
if (value?.GetPythonType().TypeId == BuiltinTypeId.Ellipsis)
{
value = Eval.UnknownType;
}
if (node.Left.FirstOrDefault() is SequenceExpression seq)
{
// Tuple = Tuple. Transfer values.
var seqHandler = new SequenceExpressionHandler(Walker);
seqHandler.HandleAssignment(seq.Items, node.Right, value);
return;
}
// Process annotations, if any.
foreach (var expr in node.Left.OfType <ExpressionWithAnnotation>())
{
// x: List[str] = [...]
HandleAnnotatedExpression(expr, value);
}
foreach (var ne in node.Left.OfType <NameExpression>())
{
if (Eval.CurrentScope.NonLocals[ne.Name] != null)
{
Eval.LookupNameInScopes(ne.Name, out var scope, LookupOptions.Nonlocal);
scope?.Variables[ne.Name].Assign(value, Eval.GetLocationOfName(ne));
continue;
}
if (Eval.CurrentScope.Globals[ne.Name] != null)
{
Eval.LookupNameInScopes(ne.Name, out var scope, LookupOptions.Global);
scope?.Variables[ne.Name].Assign(value, Eval.GetLocationOfName(ne));
continue;
}
var source = value.IsGeneric() ? VariableSource.Generic : VariableSource.Declaration;
var location = Eval.GetLocationOfName(ne);
if (IsValidAssignment(ne.Name, location))
{
Eval.DeclareVariable(ne.Name, value ?? Module.Interpreter.UnknownType, source, location);
}
}
TryHandleClassVariable(node, value);
}