Exemplo n.º 1
0
func (c *typeFilterConstraint) solve(a *analysis, delta *nodeset) {
	for _, x := range delta.AppendTo(a.deltaSpace) {
		ifaceObj := nodeid(x)
		tDyn, _, indirect := a.taggedValue(ifaceObj)
		if indirect {
			// TODO(adonovan): we'll need to implement this
			// when we start creating indirect tagged objects.
			panic("indirect tagged object")
		}

		if types.AssignableTo(tDyn, c.typ) {
			if a.addLabel(c.dst, ifaceObj) {
				a.addWork(c.dst)
			}
		}
	}
}
Exemplo n.º 2
0
// findVisibleConsts returns a mapping from each package-level constant assignable to type "error", to nil.
func findVisibleConsts(prog *ssa.Program, qpos *QueryPos) map[ssa.Const]*ssa.NamedConst {
	constants := make(map[ssa.Const]*ssa.NamedConst)
	for _, pkg := range prog.AllPackages() {
		for _, mem := range pkg.Members {
			obj, ok := mem.(*ssa.NamedConst)
			if !ok {
				continue
			}
			consttype := obj.Type()
			if !types.AssignableTo(consttype, builtinErrorType) {
				continue
			}
			if !isAccessibleFrom(obj.Object(), qpos.info.Pkg) {
				continue
			}
			constants[*obj.Value] = obj
		}
	}

	return constants
}
Exemplo n.º 3
0
// Implements displays the "implements" relation as it pertains to the
// selected type.  If the selection is a method, 'implements' displays
// the corresponding methods of the types that would have been reported
// by an implements query on the receiver type.
//
func implements(o *Oracle, qpos *QueryPos) (queryResult, error) {
	// Find the selected type.
	path, action := findInterestingNode(qpos.info, qpos.path)

	var method *types.Func
	var T types.Type // selected type (receiver if method != nil)

	switch action {
	case actionExpr:
		// method?
		if id, ok := path[0].(*ast.Ident); ok {
			if obj, ok := qpos.info.ObjectOf(id).(*types.Func); ok {
				recv := obj.Type().(*types.Signature).Recv()
				if recv == nil {
					return nil, fmt.Errorf("this function is not a method")
				}
				method = obj
				T = recv.Type()
			}
		}
	case actionType:
		T = qpos.info.TypeOf(path[0].(ast.Expr))
	}
	if T == nil {
		return nil, fmt.Errorf("no type or method here")
	}

	// Find all named types, even local types (which can have
	// methods via promotion) and the built-in "error".
	//
	// TODO(adonovan): include all packages in PTA scope too?
	// i.e. don't reduceScope?
	//
	var allNamed []types.Type
	for _, info := range o.typeInfo {
		for _, obj := range info.Defs {
			if obj, ok := obj.(*types.TypeName); ok {
				allNamed = append(allNamed, obj.Type())
			}
		}
	}
	allNamed = append(allNamed, types.Universe.Lookup("error").Type())

	var msets types.MethodSetCache

	// Test each named type.
	var to, from, fromPtr []types.Type
	for _, U := range allNamed {
		if isInterface(T) {
			if msets.MethodSet(T).Len() == 0 {
				continue // empty interface
			}
			if isInterface(U) {
				if msets.MethodSet(U).Len() == 0 {
					continue // empty interface
				}

				// T interface, U interface
				if !types.Identical(T, U) {
					if types.AssignableTo(U, T) {
						to = append(to, U)
					}
					if types.AssignableTo(T, U) {
						from = append(from, U)
					}
				}
			} else {
				// T interface, U concrete
				if types.AssignableTo(U, T) {
					to = append(to, U)
				} else if pU := types.NewPointer(U); types.AssignableTo(pU, T) {
					to = append(to, pU)
				}
			}
		} else if isInterface(U) {
			if msets.MethodSet(U).Len() == 0 {
				continue // empty interface
			}

			// T concrete, U interface
			if types.AssignableTo(T, U) {
				from = append(from, U)
			} else if pT := types.NewPointer(T); types.AssignableTo(pT, U) {
				fromPtr = append(fromPtr, U)
			}
		}
	}

	var pos interface{} = qpos
	if nt, ok := deref(T).(*types.Named); ok {
		pos = nt.Obj()
	}

	// Sort types (arbitrarily) to ensure test determinism.
	sort.Sort(typesByString(to))
	sort.Sort(typesByString(from))
	sort.Sort(typesByString(fromPtr))

	var toMethod, fromMethod, fromPtrMethod []*types.Selection // contain nils
	if method != nil {
		for _, t := range to {
			toMethod = append(toMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
		for _, t := range from {
			fromMethod = append(fromMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
		for _, t := range fromPtr {
			fromPtrMethod = append(fromPtrMethod,
				types.NewMethodSet(t).Lookup(method.Pkg(), method.Name()))
		}
	}

	return &implementsResult{qpos, T, pos, to, from, fromPtr, method, toMethod, fromMethod, fromPtrMethod}, nil
}