Golang astutil.RemoveParens函数代码示例

func (c *funcContext) translateAssign(lhs ast.Expr, rhs string, typ types.Type, define bool) string {
	lhs = astutil.RemoveParens(lhs)
	if isBlank(lhs) {
		panic("translateAssign with blank lhs")
	}

	isReflectValue := false
	if named, ok := typ.(*types.Named); ok && named.Obj().Pkg() != nil && named.Obj().Pkg().Path() == "reflect" && named.Obj().Name() == "Value" {
		isReflectValue = true
	}
	if !isReflectValue { // this is a performance hack, but it is safe since reflect.Value has no exported fields and the reflect package does not violate this assumption
		switch typ.Underlying().(type) {
		case *types.Array, *types.Struct:
			if define {
				return fmt.Sprintf("%s = $clone(%s, %s);", c.translateExpr(lhs), rhs, c.typeName(typ))
			}
			return fmt.Sprintf("$copy(%s, %s, %s);", c.translateExpr(lhs), rhs, c.typeName(typ))
		}
	}

	switch l := lhs.(type) {
	case *ast.Ident:
		o := c.p.Defs[l]
		if o == nil {
			o = c.p.Uses[l]
		}
		return fmt.Sprintf("%s = %s;", c.objectName(o), rhs)
	case *ast.SelectorExpr:
		sel, ok := c.p.Selections[l]
		if !ok {
			// qualified identifier
			return fmt.Sprintf("%s = %s;", c.objectName(c.p.Uses[l.Sel]), rhs)
		}
		fields, jsTag := c.translateSelection(sel, l.Pos())
		if jsTag != "" {
			return fmt.Sprintf("%s.%s.%s = %s;", c.translateExpr(l.X), strings.Join(fields, "."), jsTag, c.externalize(rhs, sel.Type()))
		}
		return fmt.Sprintf("%s.%s = %s;", c.translateExpr(l.X), strings.Join(fields, "."), rhs)
	case *ast.StarExpr:
		return fmt.Sprintf("%s.$set(%s);", c.translateExpr(l.X), rhs)
	case *ast.IndexExpr:
		switch t := c.p.Types[l.X].Type.Underlying().(type) {
		case *types.Array, *types.Pointer:
			pattern := rangeCheck("%1e[%2f] = %3s", c.p.Types[l.Index].Value != nil, true)
			if _, ok := t.(*types.Pointer); ok { // check pointer for nix (attribute getter causes a panic)
				pattern = `%1e.nilCheck, ` + pattern
			}
			return c.formatExpr(pattern, l.X, l.Index, rhs).String() + ";"
		case *types.Slice:
			return c.formatExpr(rangeCheck("%1e.$array[%1e.$offset + %2f] = %3s", c.p.Types[l.Index].Value != nil, false), l.X, l.Index, rhs).String() + ";"
		default:
			panic(fmt.Sprintf("Unhandled lhs type: %T\n", t))
		}
	default:
		panic(fmt.Sprintf("Unhandled lhs type: %T\n", l))
	}
}

//.........这里部分代码省略.........
				v := c.newVariable("_arg")
				vars[i] = v
				callArgs[i] = c.newIdent(v, c.p.Types[arg].Type)
			}
			call := c.translateExpr(&ast.CallExpr{
				Fun:      s.Call.Fun,
				Args:     callArgs,
				Ellipsis: s.Call.Ellipsis,
			})
			c.Printf("$deferred.push([function(%s) { %s; }, [%s]]);", strings.Join(vars, ", "), call, strings.Join(args, ", "))
			return
		}
		c.Printf("$deferred.push([%s, [%s]]);", c.translateExpr(s.Call.Fun), strings.Join(args, ", "))

	case *ast.AssignStmt:
		if s.Tok != token.ASSIGN && s.Tok != token.DEFINE {
			panic(s.Tok)
		}

		if s.Tok == token.DEFINE {
			for _, lhs := range s.Lhs {
				if !isBlank(lhs) {
					obj := c.p.Defs[lhs.(*ast.Ident)]
					if obj == nil {
						obj = c.p.Uses[lhs.(*ast.Ident)]
					}
					c.setType(lhs, obj.Type())
				}
			}
		}

		switch {
		case len(s.Lhs) == 1 && len(s.Rhs) == 1:
			lhs := astutil.RemoveParens(s.Lhs[0])
			if isBlank(lhs) {
				if analysis.HasSideEffect(s.Rhs[0], c.p.Info.Info) {
					c.Printf("%s;", c.translateExpr(s.Rhs[0]).String())
				}
				return
			}
			lhsType := c.p.Types[s.Lhs[0]].Type
			c.Printf("%s", c.translateAssignOfExpr(lhs, s.Rhs[0], lhsType, s.Tok == token.DEFINE))

		case len(s.Lhs) > 1 && len(s.Rhs) == 1:
			tupleVar := c.newVariable("_tuple")
			out := tupleVar + " = " + c.translateExpr(s.Rhs[0]).String() + ";"
			tuple := c.p.Types[s.Rhs[0]].Type.(*types.Tuple)
			for i, lhs := range s.Lhs {
				lhs = astutil.RemoveParens(lhs)
				if !isBlank(lhs) {
					lhsType := c.p.Types[s.Lhs[i]].Type
					out += " " + c.translateAssignOfExpr(lhs, c.newIdent(fmt.Sprintf("%s[%d]", tupleVar, i), tuple.At(i).Type()), lhsType, s.Tok == token.DEFINE)
				}
			}
			c.Printf("%s", out)
		case len(s.Lhs) == len(s.Rhs):
			tmpVars := make([]string, len(s.Rhs))
			var parts []string
			for i, rhs := range s.Rhs {
				tmpVars[i] = c.newVariable("_tmp")
				if isBlank(astutil.RemoveParens(s.Lhs[i])) {
					if analysis.HasSideEffect(rhs, c.p.Info.Info) {
						c.Printf("%s;", c.translateExpr(rhs).String())
					}
					continue
				}

//.........这里部分代码省略.........
				}
			}
			return c.formatExpr("new %s.ptr(%s)", c.typeName(exprType), strings.Join(elements, ", "))
		default:
			panic(fmt.Sprintf("Unhandled CompositeLit type: %T\n", t))
		}

	case *ast.FuncLit:
		_, fun := translateFunction(e.Type, nil, e.Body, c, exprType.(*types.Signature), c.p.FuncLitInfos[e], "")
		if len(c.p.escapingVars) != 0 {
			names := make([]string, 0, len(c.p.escapingVars))
			for obj := range c.p.escapingVars {
				names = append(names, c.p.objectNames[obj])
			}
			sort.Strings(names)
			list := strings.Join(names, ", ")
			return c.formatExpr("(function(%s) { return %s; })(%s)", list, fun, list)
		}
		return c.formatExpr("(%s)", fun)

	case *ast.UnaryExpr:
		t := c.p.TypeOf(e.X)
		switch e.Op {
		case token.AND:
			if typesutil.IsJsObject(exprType) {
				return c.formatExpr("%e.object", e.X)
			}

			switch t.Underlying().(type) {
			case *types.Struct, *types.Array:
				return c.translateExpr(e.X)
			}

			switch x := astutil.RemoveParens(e.X).(type) {
			case *ast.CompositeLit:
				return c.formatExpr("$newDataPointer(%e, %s)", x, c.typeName(c.p.TypeOf(e)))
			case *ast.Ident:
				obj := c.p.Uses[x].(*types.Var)
				if c.p.escapingVars[obj] {
					return c.formatExpr("(%1s.$ptr || (%1s.$ptr = new %2s(function() { return this.$target[0]; }, function($v) { this.$target[0] = $v; }, %1s)))", c.p.objectNames[obj], c.typeName(exprType))
				}
				return c.formatExpr(`(%1s || (%1s = new %2s(function() { return %3s; }, function($v) { %4s })))`, c.varPtrName(obj), c.typeName(exprType), c.objectName(obj), c.translateAssign(x, c.newIdent("$v", exprType), false))
			case *ast.SelectorExpr:
				sel, ok := c.p.Selections[x]
				if !ok {
					// qualified identifier
					obj := c.p.Uses[x.Sel].(*types.Var)
					return c.formatExpr(`(%1s || (%1s = new %2s(function() { return %3s; }, function($v) { %4s })))`, c.varPtrName(obj), c.typeName(exprType), c.objectName(obj), c.translateAssign(x, c.newIdent("$v", exprType), false))
				}
				newSel := &ast.SelectorExpr{X: c.newIdent("this.$target", c.p.TypeOf(x.X)), Sel: x.Sel}
				c.setType(newSel, exprType)
				c.p.Selections[newSel] = sel
				return c.formatExpr("(%1e.$ptr_%2s || (%1e.$ptr_%2s = new %3s(function() { return %4e; }, function($v) { %5s }, %1e)))", x.X, x.Sel.Name, c.typeName(exprType), newSel, c.translateAssign(newSel, c.newIdent("$v", exprType), false))
			case *ast.IndexExpr:
				if _, ok := c.p.TypeOf(x.X).Underlying().(*types.Slice); ok {
					return c.formatExpr("$indexPtr(%1e.$array, %1e.$offset + %2e, %3s)", x.X, x.Index, c.typeName(exprType))
				}
				return c.formatExpr("$indexPtr(%e, %e, %s)", x.X, x.Index, c.typeName(exprType))
			case *ast.StarExpr:
				return c.translateExpr(x.X)
			default:
				panic(fmt.Sprintf("Unhandled: %T\n", x))
			}

		case token.ARROW:
			call := &ast.CallExpr{

func (c *FuncInfo) Visit(node ast.Node) ast.Visitor {
	if node == nil {
		if len(c.analyzeStack) != 0 {
			c.analyzeStack = c.analyzeStack[:len(c.analyzeStack)-1]
		}
		return nil
	}
	c.analyzeStack = append(c.analyzeStack, node)

	switch n := node.(type) {
	case *ast.FuncDecl:
		newInfo := c.p.newFuncInfo()
		c.p.FuncDeclInfos[c.p.Defs[n.Name].(*types.Func)] = newInfo
		return newInfo
	case *ast.FuncLit:
		newInfo := c.p.newFuncInfo()
		c.p.FuncLitInfos[n] = newInfo
		return newInfo
	case *ast.BranchStmt:
		switch n.Tok {
		case token.GOTO:
			for _, n2 := range c.analyzeStack {
				c.Flattened[n2] = true
			}
			c.GotoLabel[c.p.Uses[n.Label].(*types.Label)] = true
		case token.CONTINUE:
			if n.Label != nil {
				label := c.p.Uses[n.Label].(*types.Label)
				for i := len(c.analyzeStack) - 1; i >= 0; i-- {
					if labelStmt, ok := c.analyzeStack[i].(*ast.LabeledStmt); ok && c.p.Defs[labelStmt.Label] == label {
						if _, ok := labelStmt.Stmt.(*ast.RangeStmt); ok {
							return nil
						}
						stack := make([]ast.Node, len(c.analyzeStack))
						copy(stack, c.analyzeStack)
						c.ContinueStmts = append(c.ContinueStmts, continueStmt{labelStmt.Stmt.(*ast.ForStmt), stack})
						return nil
					}
				}
				return nil
			}
			for i := len(c.analyzeStack) - 1; i >= 0; i-- {
				if _, ok := c.analyzeStack[i].(*ast.RangeStmt); ok {
					return nil
				}
				if forStmt, ok := c.analyzeStack[i].(*ast.ForStmt); ok {
					stack := make([]ast.Node, len(c.analyzeStack))
					copy(stack, c.analyzeStack)
					c.ContinueStmts = append(c.ContinueStmts, continueStmt{forStmt, stack})
					return nil
				}
			}
		}
	case *ast.CallExpr:
		callTo := func(obj types.Object) {
			switch o := obj.(type) {
			case *types.Func:
				if recv := o.Type().(*types.Signature).Recv(); recv != nil {
					if _, ok := recv.Type().Underlying().(*types.Interface); ok {
						c.markBlocking(c.analyzeStack)
						return
					}
				}
				if o.Pkg() != c.p.Pkg {
					if c.p.IsBlocking(o) {
						c.markBlocking(c.analyzeStack)
					}
					return
				}
				stack := make([]ast.Node, len(c.analyzeStack))
				copy(stack, c.analyzeStack)
				c.LocalCalls[o] = append(c.LocalCalls[o], stack)
			case *types.Var:
				c.markBlocking(c.analyzeStack)
			}
		}
		switch f := astutil.RemoveParens(n.Fun).(type) {
		case *ast.Ident:
			callTo(c.p.Uses[f])
		case *ast.SelectorExpr:
			if sel := c.p.Selections[f]; sel != nil && typesutil.IsJsObject(sel.Recv()) {
				break
			}
			callTo(c.p.Uses[f.Sel])
		case *ast.FuncLit:
			ast.Walk(c, n.Fun)
			for _, arg := range n.Args {
				ast.Walk(c, arg)
			}
			if len(c.p.FuncLitInfos[f].Blocking) != 0 {
				c.markBlocking(c.analyzeStack)
			}
			return nil
		default:
			if !astutil.IsTypeExpr(f, c.p.Info) {
				c.markBlocking(c.analyzeStack)
			}
		}
	case *ast.SendStmt:
		c.markBlocking(c.analyzeStack)
//.........这里部分代码省略.........

func (c *funcContext) translateAssign(lhs, rhs ast.Expr, define bool) string {
	lhs = astutil.RemoveParens(lhs)
	if isBlank(lhs) {
		panic("translateAssign with blank lhs")
	}

	if l, ok := lhs.(*ast.IndexExpr); ok {
		if t, ok := c.p.TypeOf(l.X).Underlying().(*types.Map); ok {
			if typesutil.IsJsObject(c.p.TypeOf(l.Index)) {
				c.p.errList = append(c.p.errList, types.Error{Fset: c.p.fileSet, Pos: l.Index.Pos(), Msg: "cannot use js.Object as map key"})
			}
			keyVar := c.newVariable("_key")
			return fmt.Sprintf(`%s = %s; (%s || $throwRuntimeError("assignment to entry in nil map"))[%s.keyFor(%s)] = { k: %s, v: %s };`, keyVar, c.translateImplicitConversionWithCloning(l.Index, t.Key()), c.translateExpr(l.X), c.typeName(t.Key()), keyVar, keyVar, c.translateImplicitConversionWithCloning(rhs, t.Elem()))
		}
	}

	lhsType := c.p.TypeOf(lhs)
	rhsExpr := c.translateImplicitConversion(rhs, lhsType)
	if _, ok := rhs.(*ast.CompositeLit); ok && define {
		return fmt.Sprintf("%s = %s;", c.translateExpr(lhs), rhsExpr) // skip $copy
	}

	isReflectValue := false
	if named, ok := lhsType.(*types.Named); ok && named.Obj().Pkg() != nil && named.Obj().Pkg().Path() == "reflect" && named.Obj().Name() == "Value" {
		isReflectValue = true
	}
	if !isReflectValue { // this is a performance hack, but it is safe since reflect.Value has no exported fields and the reflect package does not violate this assumption
		switch lhsType.Underlying().(type) {
		case *types.Array, *types.Struct:
			if define {
				return fmt.Sprintf("%s = $clone(%s, %s);", c.translateExpr(lhs), rhsExpr, c.typeName(lhsType))
			}
			return fmt.Sprintf("%s.copy(%s, %s);", c.typeName(lhsType), c.translateExpr(lhs), rhsExpr)
		}
	}

	switch l := lhs.(type) {
	case *ast.Ident:
		return fmt.Sprintf("%s = %s;", c.objectName(c.p.ObjectOf(l)), rhsExpr)
	case *ast.SelectorExpr:
		sel, ok := c.p.SelectionOf(l)
		if !ok {
			// qualified identifier
			return fmt.Sprintf("%s = %s;", c.objectName(c.p.Uses[l.Sel]), rhsExpr)
		}
		fields, jsTag := c.translateSelection(sel, l.Pos())
		if jsTag != "" {
			return fmt.Sprintf("%s.%s.%s = %s;", c.translateExpr(l.X), strings.Join(fields, "."), jsTag, c.externalize(rhsExpr.String(), sel.Type()))
		}
		return fmt.Sprintf("%s.%s = %s;", c.translateExpr(l.X), strings.Join(fields, "."), rhsExpr)
	case *ast.StarExpr:
		return fmt.Sprintf("%s.$set(%s);", c.translateExpr(l.X), rhsExpr)
	case *ast.IndexExpr:
		switch t := c.p.TypeOf(l.X).Underlying().(type) {
		case *types.Array, *types.Pointer:
			pattern := rangeCheck("%1e[%2f] = %3s", c.p.Types[l.Index].Value != nil, true)
			if _, ok := t.(*types.Pointer); ok { // check pointer for nil (attribute getter causes a panic)
				pattern = `%1e.nilCheck, ` + pattern
			}
			return c.formatExpr(pattern, l.X, l.Index, rhsExpr).String() + ";"
		case *types.Slice:
			return c.formatExpr(rangeCheck("%1e.$array[%1e.$offset + %2f] = %3s", c.p.Types[l.Index].Value != nil, false), l.X, l.Index, rhsExpr).String() + ";"
		default:
			panic(fmt.Sprintf("Unhandled lhs type: %T\n", t))
		}
	default:
		panic(fmt.Sprintf("Unhandled lhs type: %T\n", l))
	}
}

func Assign(stmt ast.Stmt, info *analysis.Info) ast.Stmt {
	if s, ok := stmt.(*ast.AssignStmt); ok && s.Tok != token.ASSIGN && s.Tok != token.DEFINE {
		var op token.Token
		switch s.Tok {
		case token.ADD_ASSIGN:
			op = token.ADD
		case token.SUB_ASSIGN:
			op = token.SUB
		case token.MUL_ASSIGN:
			op = token.MUL
		case token.QUO_ASSIGN:
			op = token.QUO
		case token.REM_ASSIGN:
			op = token.REM
		case token.AND_ASSIGN:
			op = token.AND
		case token.OR_ASSIGN:
			op = token.OR
		case token.XOR_ASSIGN:
			op = token.XOR
		case token.SHL_ASSIGN:
			op = token.SHL
		case token.SHR_ASSIGN:
			op = token.SHR
		case token.AND_NOT_ASSIGN:
			op = token.AND_NOT
		default:
			panic(s.Tok)
		}

		var list []ast.Stmt

		var viaTmpVars func(expr ast.Expr, name string) ast.Expr
		viaTmpVars = func(expr ast.Expr, name string) ast.Expr {
			switch e := astutil.RemoveParens(expr).(type) {
			case *ast.IndexExpr:
				return astutil.SetType(info.Info, info.TypeOf(e), &ast.IndexExpr{
					X:     viaTmpVars(e.X, "_slice"),
					Index: viaTmpVars(e.Index, "_index"),
				})

			case *ast.SelectorExpr:
				sel, ok := info.Selections[e]
				if !ok {
					// qualified identifier
					return e
				}
				newSel := &ast.SelectorExpr{
					X:   viaTmpVars(e.X, "_struct"),
					Sel: e.Sel,
				}
				info.Selections[newSel] = sel
				return astutil.SetType(info.Info, info.TypeOf(e), newSel)

			case *ast.StarExpr:
				return astutil.SetType(info.Info, info.TypeOf(e), &ast.StarExpr{
					X: viaTmpVars(e.X, "_ptr"),
				})

			case *ast.Ident, *ast.BasicLit:
				return e

			default:
				tmpVar := astutil.NewIdent(name, info.TypeOf(e), info.Info, info.Pkg)
				list = append(list, &ast.AssignStmt{
					Lhs: []ast.Expr{tmpVar},
					Tok: token.DEFINE,
					Rhs: []ast.Expr{e},
				})
				return tmpVar

			}
		}

		lhs := viaTmpVars(s.Lhs[0], "_val")

		list = append(list, &ast.AssignStmt{
			Lhs: []ast.Expr{lhs},
			Tok: token.ASSIGN,
			Rhs: []ast.Expr{
				astutil.SetType(info.Info, info.TypeOf(s.Lhs[0]), &ast.BinaryExpr{
					X:  lhs,
					Op: op,
					Y: astutil.SetType(info.Info, info.TypeOf(s.Rhs[0]), &ast.ParenExpr{
						X: s.Rhs[0],
					}),
				}),
			},
		})

		return &ast.BlockStmt{
			List: list,
		}
	}
	return stmt
}