如何在 dart 中使用 Analyzer 编辑节点答案

【问题标题】：how to edit node using Analyser in dart如何在 dart 中使用 Analyzer 编辑节点
【发布时间】：2018-11-13 17:09:00
【问题描述】：

如何使用分析器在 dart 中编辑源文件。这是我尝试过的

import 'package:analyzer/src/generated/ast.dart';
import 'package:analyzer/src/generated/error.dart';
import 'package:analyzer/src/generated/parser.dart';
import 'package:analyzer/src/generated/scanner.dart';

String src = """
Dynamism d = new Dynamism(expert:true);
main(){
var o = new Object();
d.on(o).hi = 'bye';
}
""";
main() {
var ast = parseCompilationUnit(src, parseFunctionBodies: true);
print('initial value: ');
print(ast.toSource());
var v = new Visitor();
ast.visitChildren(v);
print('After modification:');
print(ast.toSource());
}
class Visitor extends RecursiveAstVisitor {
@override
 visitAssignmentExpression(AssignmentExpression node) {
//filter
var p = new RegExp(r'.*\.on\(\w\)');
if (!p.hasMatch(node.toString())) return;

//replace
SimpleStringLiteral ssl = _create_SimpleStringLiteral(node);
node.parent.accept(new NodeReplacer(node, ssl));
}
}

SimpleStringLiteral _create_SimpleStringLiteral(AstNode node) {
String new_string = modify(node.toString());
int line_num = node.offset;
//holds the position and type
StringToken st = new StringToken(TokenType.STRING, new_string, 
line_num);
return new SimpleStringLiteral(st, new_string);
}

String modify(String s) {
List parts = s.split('=');
var value = parts[1];
List l = parts[0].split('.');
String dynamism = l.sublist(0, l.length - 1).join('.');
String propertyName = l.last.trim();
return '${dynamism}.set("${propertyName}",${value})';
}

但它在 SimpleStringLiteral 上抛出错误，说它是一个抽象类。请帮我将“再见”编辑为“再见”。我认为以前版本的 dart 有它的实现，但现在它是抽象的。

【问题讨论】：

标签： dart dart-analyzer

【解决方案1】：

而不是使用 return new SimpleStringLiteral(st, new_string) 试试 返回 astFactory.simpleStringLiteral(st, new_string);

import 'package:analyzer/src/generated/ast.dart';
import 'package:analyzer/dart/ast/standard_ast_factory.dart';
import 'package:analyzer/src/generated/error.dart';
import 'package:analyzer/src/generated/parser.dart';
import 'package:analyzer/src/generated/scanner.dart';

String src = """
Dynamism d = new Dynamism(expert:true);
main(){
var o = new Object();
d.on(o).hi = 'bye';
}
""";
main() {
var ast = parseCompilationUnit(src, parseFunctionBodies: true);
print('initial value: ');
print(ast.toSource());
var v = new Visitor();
ast.visitChildren(v);
print('After modification:');
print(ast.toSource());
}
class Visitor extends RecursiveAstVisitor {
@override
 visitAssignmentExpression(AssignmentExpression node) {
//filter
var p = new RegExp(r'.*\.on\(\w\)');
if (!p.hasMatch(node.toString())) return;

//replace
SimpleStringLiteral ssl = _create_SimpleStringLiteral(node);
node.parent.accept(new NodeReplacer(node, ssl));
}
}

SimpleStringLiteral _create_SimpleStringLiteral(AstNode node) {
String new_string = modify(node.toString());
int line_num = node.offset;
//holds the position and type
StringToken st = new StringToken(TokenType.STRING, new_string, 
line_num);
return astFactory.simpleStringLiteral(st, new_string);
}

String modify(String s) {
List parts = s.split('=');
var value = parts[1];
List l = parts[0].split('.');
String dynamism = l.sublist(0, l.length - 1).join('.');
String propertyName = l.last.trim();
return '${dynamism}.set("${propertyName}",${value})';
}

【讨论】：