Golang Object.Pkg方法代码示例

//getFullName is returning unique name of obj.
func getFullName(obj types.Object, ctx *getDefinitionsContext, isType bool) string {
	if obj == nil {
		return ""
	}
	if isType {
		return obj.Type().String()
	}

	result := ""

	switch obj.(type) {
	case *types.Func:
		f := obj.(*types.Func)
		r := strings.NewReplacer("(", "", "*", "", ")", "")
		result = r.Replace(f.FullName())
	default:
		if obj.Pkg() != nil {
			result += obj.Pkg().Path()
			result += "."
		}

		if packageName, ok := ctx.structs[posToStr(ctx.fset, obj.Pos())]; ok {
			result += packageName
			result += "."
		}
		result += obj.Name()
	}

	return result
}

func formatMember(obj types.Object, maxname int) string {
	qualifier := types.RelativeTo(obj.Pkg())
	var buf bytes.Buffer
	fmt.Fprintf(&buf, "%-5s %-*s", tokenOf(obj), maxname, obj.Name())
	switch obj := obj.(type) {
	case *types.Const:
		fmt.Fprintf(&buf, " %s = %s", types.TypeString(obj.Type(), qualifier), obj.Val().String())

	case *types.Func:
		fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type(), qualifier))

	case *types.TypeName:
		// Abbreviate long aggregate type names.
		var abbrev string
		switch t := obj.Type().Underlying().(type) {
		case *types.Interface:
			if t.NumMethods() > 1 {
				abbrev = "interface{...}"
			}
		case *types.Struct:
			if t.NumFields() > 1 {
				abbrev = "struct{...}"
			}
		}
		if abbrev == "" {
			fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type().Underlying(), qualifier))
		} else {
			fmt.Fprintf(&buf, " %s", abbrev)
		}

	case *types.Var:
		fmt.Fprintf(&buf, " %s", types.TypeString(obj.Type(), qualifier))
	}
	return buf.String()
}

// checkSelection checks that all uses and selections that resolve to
// the specified object would continue to do so after the renaming.
func (r *renamer) checkSelections(from types.Object) {
	for pkg, info := range r.packages {
		if id := someUse(info, from); id != nil {
			if !r.checkExport(id, pkg, from) {
				return
			}
		}

		for syntax, sel := range info.Selections {
			// There may be extant selections of only the old
			// name or only the new name, so we must check both.
			// (If neither, the renaming is sound.)
			//
			// In both cases, we wish to compare the lengths
			// of the implicit field path (Selection.Index)
			// to see if the renaming would change it.
			//
			// If a selection that resolves to 'from', when renamed,
			// would yield a path of the same or shorter length,
			// this indicates ambiguity or a changed referent,
			// analogous to same- or sub-block lexical conflict.
			//
			// If a selection using the name 'to' would
			// yield a path of the same or shorter length,
			// this indicates ambiguity or shadowing,
			// analogous to same- or super-block lexical conflict.

			// TODO(adonovan): fix: derive from Types[syntax.X].Mode
			// TODO(adonovan): test with pointer, value, addressable value.
			isAddressable := true

			if sel.Obj() == from {
				if obj, indices, _ := types.LookupFieldOrMethod(sel.Recv(), isAddressable, from.Pkg(), r.to); obj != nil {
					// Renaming this existing selection of
					// 'from' may block access to an existing
					// type member named 'to'.
					delta := len(indices) - len(sel.Index())
					if delta > 0 {
						continue // no ambiguity
					}
					r.selectionConflict(from, delta, syntax, obj)
					return
				}

			} else if sel.Obj().Name() == r.to {
				if obj, indices, _ := types.LookupFieldOrMethod(sel.Recv(), isAddressable, from.Pkg(), from.Name()); obj == from {
					// Renaming 'from' may cause this existing
					// selection of the name 'to' to change
					// its meaning.
					delta := len(indices) - len(sel.Index())
					if delta > 0 {
						continue //  no ambiguity
					}
					r.selectionConflict(from, -delta, syntax, sel.Obj())
					return
				}
			}
		}
	}
}

func createDef(obj types.Object, ident *ast.Ident, ctx *getDefinitionsContext, isType bool) *Definition {
	fullName := getFullName(obj, ctx, isType)

	if def, ok := ctx.defs[fullName]; ok {
		return def
	}

	def := new(Definition)
	def.Name = fullName
	def.Pkg = obj.Pkg()
	def.IsExported = obj.Exported()
	def.TypeOf = reflect.TypeOf(obj)
	def.SimpleName = obj.Name()
	def.Usages = make([]*Usage, 0)
	def.InterfacesDefs = make([]*Definition, 0)

	if ident != nil {
		position := ctx.fset.Position(ident.Pos())
		def.File = position.Filename
		def.Line = position.Line
		def.Offset = position.Offset
		def.Col = position.Column
	}

	if !types.IsInterface(obj.Type()) {
		fillInterfaces(def, obj, ctx)
	}

	ctx.defs[def.Name] = def
	logDefinition(def, obj, ident, ctx)

	return def
}

func (r *renamer) checkInLocalScope(from types.Object) {
	info := r.packages[from.Pkg()]

	// Is this object an implicit local var for a type switch?
	// Each case has its own var, whose position is the decl of y,
	// but Ident in that decl does not appear in the Uses map.
	//
	//   switch y := x.(type) {	 // Defs[Ident(y)] is undefined
	//   case int:    print(y)       // Implicits[CaseClause(int)]    = Var(y_int)
	//   case string: print(y)       // Implicits[CaseClause(string)] = Var(y_string)
	//   }
	//
	var isCaseVar bool
	for syntax, obj := range info.Implicits {
		if _, ok := syntax.(*ast.CaseClause); ok && obj.Pos() == from.Pos() {
			isCaseVar = true
			r.check(obj)
		}
	}

	r.checkInLexicalScope(from, info)

	// Finally, if this was a type switch, change the variable y.
	if isCaseVar {
		_, path, _ := r.iprog.PathEnclosingInterval(from.Pos(), from.Pos())
		path[0].(*ast.Ident).Name = r.to // path is [Ident AssignStmt TypeSwitchStmt...]
	}
}

func (b *candidateCollector) appendObject(obj types.Object) {
	// TODO(mdempsky): Change this to true.
	const proposeBuiltins = false

	if obj.Pkg() != b.localpkg {
		if obj.Parent() == types.Universe {
			if !proposeBuiltins {
				return
			}
		} else if !obj.Exported() {
			return
		}
	}

	// TODO(mdempsky): Reconsider this functionality.
	if b.filter != nil && !b.filter(obj) {
		return
	}

	if b.filter != nil || strings.HasPrefix(obj.Name(), b.partial) {
		b.exact = append(b.exact, obj)
	} else if strings.HasPrefix(strings.ToLower(obj.Name()), strings.ToLower(b.partial)) {
		b.badcase = append(b.badcase, obj)
	}
}

// checkInPackageBlock performs safety checks for renames of
// func/var/const/type objects in the package block.
func (r *renamer) checkInPackageBlock(from types.Object) {
	// Check that there are no references to the name from another
	// package if the renaming would make it unexported.
	if ast.IsExported(from.Name()) && !ast.IsExported(r.to) {
		for pkg, info := range r.packages {
			if pkg == from.Pkg() {
				continue
			}
			if id := someUse(info, from); id != nil &&
				!r.checkExport(id, pkg, from) {
				break
			}
		}
	}

	info := r.packages[from.Pkg()]

	// Check that in the package block, "init" is a function, and never referenced.
	if r.to == "init" {
		kind := objectKind(from)
		if kind == "func" {
			// Reject if intra-package references to it exist.
			for id, obj := range info.Uses {
				if obj == from {
					r.errorf(from.Pos(),
						"renaming this func %q to %q would make it a package initializer",
						from.Name(), r.to)
					r.errorf(id.Pos(), "\tbut references to it exist")
					break
				}
			}
		} else {
			r.errorf(from.Pos(), "you cannot have a %s at package level named %q",
				kind, r.to)
		}
	}

	// Check for conflicts between package block and all file blocks.
	for _, f := range info.Files {
		fileScope := info.Info.Scopes[f]
		b, prev := fileScope.LookupParent(r.to, token.NoPos)
		if b == fileScope {
			r.errorf(from.Pos(), "renaming this %s %q to %q would conflict",
				objectKind(from), from.Name(), r.to)
			r.errorf(prev.Pos(), "\twith this %s",
				objectKind(prev))
			return // since checkInPackageBlock would report redundant errors
		}
	}

	// Check for conflicts in lexical scope.
	if from.Exported() {
		for _, info := range r.packages {
			r.checkInLexicalScope(from, info)
		}
	} else {
		r.checkInLexicalScope(from, info)
	}
}

func (p *exporter) qualifiedName(obj types.Object) {
	if obj == nil {
		p.string("")
		return
	}
	p.string(obj.Name())
	p.pkg(obj.Pkg(), false)
}

// VName returns a VName for obj relative to that of its package.
func (pi *PackageInfo) VName(obj types.Object) *spb.VName {
	sig := pi.Signature(obj)
	base := pi.VNames[obj.Pkg()]
	if base == nil {
		return govname.ForBuiltin(sig)
	}
	vname := proto.Clone(base).(*spb.VName)
	vname.Signature = sig
	return vname
}

func (sym *symtab) addSymbol(obj types.Object) {
	fn := types.ObjectString(obj, nil)
	n := obj.Name()
	pkg := obj.Pkg()
	id := n
	if pkg != nil {
		id = pkg.Name() + "_" + n
	}
	switch obj.(type) {
	case *types.Const:
		sym.syms[fn] = &symbol{
			gopkg:   pkg,
			goobj:   obj,
			kind:    skConst,
			id:      id,
			goname:  n,
			cgoname: "cgo_const_" + id,
			cpyname: "cpy_const_" + id,
		}
		sym.addType(obj, obj.Type())

	case *types.Var:
		sym.syms[fn] = &symbol{
			gopkg:   pkg,
			goobj:   obj,
			kind:    skVar,
			id:      id,
			goname:  n,
			cgoname: "cgo_var_" + id,
			cpyname: "cpy_var_" + id,
		}
		sym.addType(obj, obj.Type())

	case *types.Func:
		sym.syms[fn] = &symbol{
			gopkg:   pkg,
			goobj:   obj,
			kind:    skFunc,
			id:      id,
			goname:  n,
			cgoname: "cgo_func_" + id,
			cpyname: "cpy_func_" + id,
		}
		sig := obj.Type().Underlying().(*types.Signature)
		sym.processTuple(sig.Params())
		sym.processTuple(sig.Results())

	case *types.TypeName:
		sym.addType(obj, obj.Type())

	default:
		panic(fmt.Errorf("gopy: handled object [%#v]", obj))
	}
}

func (p *importer) declare(obj types.Object) {
	pkg := obj.Pkg()
	if alt := pkg.Scope().Insert(obj); alt != nil {
		// This could only trigger if we import a (non-type) object a second time.
		// This should never happen because 1) we only import a package once; and
		// b) we ignore compiler-specific export data which may contain functions
		// whose inlined function bodies refer to other functions that were already
		// imported.
		// (See also the comment in cmd/compile/internal/gc/bimport.go importer.obj,
		// switch case importing functions).
		panic(fmt.Sprintf("%s already declared", alt.Name()))
	}
}

// classify classifies objects by how far
// we have to look to find references to them.
func classify(obj types.Object) (global, pkglevel bool) {
	if obj.Exported() {
		if obj.Parent() == nil {
			// selectable object (field or method)
			return true, false
		}
		if obj.Parent() == obj.Pkg().Scope() {
			// lexical object (package-level var/const/func/type)
			return true, true
		}
	}
	// object with unexported named or defined in local scope
	return false, false
}

func (r *renamer) checkExport(id *ast.Ident, pkg *types.Package, from types.Object) bool {
	// Reject cross-package references if r.to is unexported.
	// (Such references may be qualified identifiers or field/method
	// selections.)
	if !ast.IsExported(r.to) && pkg != from.Pkg() {
		r.errorf(from.Pos(),
			"renaming this %s %q to %q would make it unexported",
			objectKind(from), from.Name(), r.to)
		r.errorf(id.Pos(), "\tbreaking references from packages such as %q",
			pkg.Path())
		return false
	}
	return true
}

func getKey(obj types.Object) object {
	if obj == nil {
		return object{}
	}

	pkg := obj.Pkg()
	pkgPath := ""
	if pkg != nil {
		pkgPath = pkg.Path()
	}

	return object{
		pkgPath: pkgPath,
		name:    obj.Name(),
	}
}

func (p *importer) declare(obj types.Object) {
	pkg := obj.Pkg()
	if alt := pkg.Scope().Insert(obj); alt != nil {
		// This can only trigger if we import a (non-type) object a second time.
		// Excluding aliases, this cannot happen because 1) we only import a package
		// once; and b) we ignore compiler-specific export data which may contain
		// functions whose inlined function bodies refer to other functions that
		// were already imported.
		// However, aliases require reexporting the original object, so we need
		// to allow it (see also the comment in cmd/compile/internal/gc/bimport.go,
		// method importer.obj, switch case importing functions).
		// Note that the original itself cannot be an alias.
		if !sameObj(obj, alt) {
			errorf("inconsistent import:\n\t%v\npreviously imported as:\n\t%v\n", obj, alt)
		}
	}
}