public async Task HandleAnnotatedExpressionAsync(ExpressionWithAnnotation expr, IMember value, CancellationToken cancellationToken = default)
{
if (expr?.Annotation == null)
{
return;
}
var variableType = await Eval.GetTypeFromAnnotationAsync(expr.Annotation, cancellationToken);
// If value is null, then this is a pure declaration like
// x: List[str]
// without a value. If value is provided, then this is
// x: List[str] = [...]
// Check value type for compatibility
IMember instance = null;
if (value != null)
{
var valueType = value.GetPythonType();
if (!variableType.IsUnknown() && !valueType.Equals(variableType))
{
// TODO: warn incompatible value type.
// TODO: verify values. Value may be list() while variable type is List[str].
// Leave it as variable type.
}
else
{
instance = value;
}
}
instance = instance ?? variableType?.CreateInstance(variableType.Name, Eval.GetLoc(expr.Expression), ArgumentSet.Empty) ?? Eval.UnknownType;
if (expr.Expression is NameExpression ne)
{
Eval.DeclareVariable(ne.Name, instance, expr.Expression);
return;
}
if (expr.Expression is MemberExpression m)
{
// self.x : int = 42
var self = Eval.LookupNameInScopes("self", out var scope);
var argType = self?.GetPythonType();
if (argType is PythonClassType cls && scope != null)
{
cls.AddMember(m.Name, instance, true);
}
}
}
public override async Task EvaluateAsync(CancellationToken cancellationToken = default)
{
if (SymbolTable.ReplacedByStubs.Contains(Target))
{
return;
}
cancellationToken.ThrowIfCancellationRequested();
// Process annotations.
var annotationType = await Eval.GetTypeFromAnnotationAsync(FunctionDefinition.ReturnAnnotation, cancellationToken);
if (!annotationType.IsUnknown())
{
// Annotations are typically types while actually functions return
// instances unless specifically annotated to a type such as Type[T].
var instance = annotationType.CreateInstance(annotationType.Name, Eval.GetLoc(FunctionDefinition), ArgumentSet.Empty);
_overload.SetReturnValue(instance, true);
}
else
{
// Check if function is a generator
var suite = FunctionDefinition.Body as SuiteStatement;
var yieldExpr = suite?.Statements.OfType <ExpressionStatement>().Select(s => s.Expression as YieldExpression).ExcludeDefault().FirstOrDefault();
if (yieldExpr != null)
{
// Function return is an iterator
var yieldValue = await Eval.GetValueFromExpressionAsync(yieldExpr.Expression, cancellationToken) ?? Eval.UnknownType;
var returnValue = new PythonGenerator(Eval.Interpreter, yieldValue);
_overload.SetReturnValue(returnValue, true);
}
}
using (Eval.OpenScope(FunctionDefinition, out _)) {
await DeclareParametersAsync(cancellationToken);
if (annotationType.IsUnknown() || Module.ModuleType == ModuleType.User)
{
// Return type from the annotation is sufficient for libraries
// and stubs, no need to walk the body.
if (FunctionDefinition.Body != null && Module.ModuleType != ModuleType.Specialized)
{
await FunctionDefinition.Body.WalkAsync(this, cancellationToken);
}
}
}
}
public async Task EvaluateClassAsync(CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
// Open class scope chain
using (Eval.OpenScope(_classDef, out var outerScope)) {
var instance = Eval.GetInScope(_classDef.Name, outerScope);
if (!(instance?.GetPythonType() is PythonClassType classInfo))
{
if (instance != null)
{
// TODO: warning that variable is already declared of a different type.
}
// May be odd case like class inside a class.
return;
}
// Evaluate inner classes, if any
await EvaluateInnerClassesAsync(_classDef, cancellationToken);
_class = classInfo;
// Set bases to the class.
var bases = new List <IPythonType>();
foreach (var a in _classDef.Bases.Where(a => string.IsNullOrEmpty(a.Name)))
{
// We cheat slightly and treat base classes as annotations.
var b = await Eval.GetTypeFromAnnotationAsync(a.Expression, cancellationToken);
if (b != null)
{
bases.Add(b.GetPythonType());
}
}
_class.SetBases(Interpreter, bases);
// Declare __class__ variable in the scope.
Eval.DeclareVariable("__class__", _class, _classDef);
await ProcessClassBody(cancellationToken);
}
}
private async Task DeclareParametersAsync(CancellationToken cancellationToken = default)
{
// For class method no need to add extra parameters, but first parameter type should be the class.
// For static and unbound methods do not add or set anything.
// For regular bound methods add first parameter and set it to the class.
var parameters = new List <ParameterInfo>();
var skip = 0;
if (_self != null && _function.HasClassFirstArgument())
{
var p0 = FunctionDefinition.Parameters.FirstOrDefault();
if (p0 != null && !string.IsNullOrEmpty(p0.Name))
{
// Actual parameter type will be determined when method is invoked.
// The reason is that if method might be called on a derived class.
// Declare self or cls in this scope.
Eval.DeclareVariable(p0.Name, _self, p0.NameExpression);
// Set parameter info.
var pi = new ParameterInfo(Ast, p0, _self);
pi.SetType(_self);
parameters.Add(pi);
skip++;
}
}
// Declare parameters in scope
for (var i = skip; i < FunctionDefinition.Parameters.Length; i++)
{
cancellationToken.ThrowIfCancellationRequested();
var p = FunctionDefinition.Parameters[i];
if (!string.IsNullOrEmpty(p.Name))
{
// If parameter has default value, look for the annotation locally first
// since outer type may be getting redefined. Consider 's = None; def f(s: s = 123): ...
IPythonType paramType = null;
if (p.DefaultValue != null)
{
paramType = await Eval.GetTypeFromAnnotationAsync(p.Annotation, cancellationToken, LookupOptions.Local | LookupOptions.Builtins);
if (paramType == null)
{
var defaultValue = await Eval.GetValueFromExpressionAsync(p.DefaultValue, cancellationToken);
if (!defaultValue.IsUnknown())
{
paramType = defaultValue.GetPythonType();
}
}
}
// If all else fails, look up globally.
paramType = paramType ?? await Eval.GetTypeFromAnnotationAsync(p.Annotation, cancellationToken);
var pi = new ParameterInfo(Ast, p, paramType);
await DeclareParameterAsync(p, i, pi, cancellationToken);
parameters.Add(pi);
}
}
_overload.SetParameters(parameters);
}