我想重写代码中的所有消息,我只需要替换选择器,但我需要能够替换嵌套的表达式f.e.:
[super foo:[someInstance someMessage:@""] foo2:[someInstance someMessage2]];
我试着用CCD_ 1做这件事,然后只生成新的字符串,但有一个问题:如果我更改选择器的长度,这将不起作用,因为我用那些旧位置替换了嵌套的消息。
所以,我假设我需要使用clang::Rewriter ReplaceStmt(originalStatement, newStatement);
我正在使用RecursiveASTVisitor
访问所有消息,我想复制这些消息对象,并替换选择器:
我该怎么做?
我尝试使用ObjCMessageExpr::Create
,但参数太多,我不知道如何从原始消息中获取ASTContext &Context
、and ArrayRef<SourceLocation> SeLocs
和Expr *Receiver
参数。
使用clang工具(clang工具接口)替换嵌套消息中的选择器的正确方法是什么?
更新:
我应该使用ReplaceStmtWithStmt
回调和ASTMatchFinder
吗?
更新:
我正在使用以下功能来重写文件中的文本:
void ReplaceText(SourceLocation start, unsigned originalLength, StringRef string) {
m_rewriter.ReplaceText(start, originalLength, string);
m_rewriter.overwriteChangedFiles();
}
我想用新的选择器f.e替换代码中的所有messageExpr:情况如何:
[object someMessage:[object2 someMessage:obj3 calculate:obj4]];
应该如何:
[object newSelector:[object2 newSelector:obj3 newSelector:obj4]];
我正在使用ReoursiveAST访问者:
bool VisitStmt(Stmt *statement) {
if (ObjCMessageExpr *messageExpr = dyn_cast<ObjCMessageExpr>(statement)) {
ReplaceMessage(*messageExpr)
}
return true;
}
我创建了生成新消息表达式字符串的方法:
string StringFromObjCMessageExpr(ObjCMessageExpr& messageExpression) {
std::ostringstream stringStream;
const string selectorString = messageExpression.getSelector().getAsString();
cout << selectorString << endl;
vector<string> methodParts;
split(selectorString, ParametersDelimiter, methodParts);
stringStream << "[" ;
const string receiver = GetStringFromLocations(m_compiler, messageExpression.getReceiverRange().getBegin(), messageExpression.getSelectorStartLoc());
stringStream << receiver;
clang::ObjCMessageExpr::arg_iterator argIterator = messageExpression.arg_begin();
for (vector<string>::const_iterator partsIterator = methodParts.begin();
partsIterator != methodParts.end();
++partsIterator) {
stringStream << "newSelector";
if (messageExpression.getNumArgs() != 0) {
const clang::Stmt *argument = *argIterator;
stringStream << ":" << GetStatementString(*argument) << " ";
++argIterator;
}
}
stringStream << "]";
return stringStream.str();
}
void ReplaceMessage(ObjCMessageExpr& messageExpression) {
SourceLocation locStart = messageExpression.getLocStart();
SourceLocation locEnd = messageExpression.getLocEnd();
string newExpr = StringFromObjCMessageExpr(messageExpression);
const int exprStringLegth = m_rewriter.getRangeSize(SourceRange(locStart, locEnd));
ReplaceText(locStart, exprStringLegth, newExpr);
}
当我试图替换嵌套的消息时,就会出现问题,比如:
[simpleClass doSomeActionWithString:string3 andAnotherString:string4];
[simpleClass doSomeActionWithString:str andAnotherString:str2];
[simpleClass doSomeActionWithString:@"" andAnotherString:@"asdasdsad"];
[simpleClass setSimpleClassZAZAZAZAZAZAZAZA:[simpleClass getSimpleClassZAZAZAZAZAZAZAZA]];
结果是:
[simpleClass newSelector:string3 newSelector:string4 ];
[simpleClass newSelector:str newSelector:str2 ];
[simpleClass newSelector:@"" newSelector:@"asdasdsad" ];
[simpleClass newSelector:[simpleClass getSimp[simpleClass newSelector]];
因为messageExpression的"旧"值为clang::Rewriter replaceText
0和getLocEnd();
,我该如何修复它?
您可以通过只替换选择器名称的连续部分来重写选择器名称。例如,只更换带下划线的零件
[object someMessage:[object2 someMessage:obj3 calculate:obj4]];
^~~~~~~~~~~ ^~~~~~~~~~~ ^~~~~~~~~
要实现这一点,您只需要
- 选择器零件数量-
ObjCMessageExpr::getNumSelectorLocs()
- 他们的位置-
ObjCMessageExpr::getSelectorLoc(index)
- 其长度为CCD_ 14
总体而言,您可以使用以下递归ASTVisitor重写ObjCMessageExpr:
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/Rewrite/Core/Rewriter.h"
namespace clang_tooling
{
using clang::SourceLocation;
class RewritingVisitor : public clang::ASTConsumer,
public clang::RecursiveASTVisitor<RewritingVisitor>
{
public:
// You can obtain SourceManager and LangOptions from CompilerInstance when
// you are creating visitor (which is also ASTConsumer) in
// clang::ASTFrontendAction::CreateASTConsumer.
RewritingVisitor(clang::SourceManager &sourceManager,
const clang::LangOptions &langOptions)
: _sourceManager(sourceManager), _rewriter(sourceManager, langOptions)
{}
virtual void HandleTranslationUnit(clang::ASTContext &context)
{
TraverseDecl(context.getTranslationUnitDecl());
_rewriter.overwriteChangedFiles();
}
bool VisitObjCMessageExpr(clang::ObjCMessageExpr *messageExpr)
{
if (_sourceManager.isInMainFile(messageExpr->getLocStart()))
{
clang::Selector selector = messageExpr->getSelector();
for (unsigned i = 0, end = messageExpr->getNumSelectorLocs();
i < end; ++i)
{
SourceLocation selectorLoc = messageExpr->getSelectorLoc(i);
_rewriter.ReplaceText(selectorLoc,
selector.getNameForSlot(i).size(),
"newSelector");
}
}
return Base::VisitObjCMessageExpr(messageExpr);
}
private:
typedef clang::RecursiveASTVisitor<RewritingVisitor> Base;
clang::SourceManager &_sourceManager;
clang::Rewriter _rewriter;
};
} // end namespace clang_tooling