Лабораторная работа №3. Зайцев Александр 381906-1

[R1der-on-The-Storm]

No description provided.

[R1der-on-The-Storm]

[ElizJogar]

Please describe the reason of using theLexer::getLocForEndOfToken() function here.
What would be the difference if rewriter.InsertText(styleCastExpr->getEndLoc().getLocOffset(1), ")"); was used here?
What would be the difference if rewriter.InsertTextAfterToken(styleCastExpr->getEndLoc(), ")"); was used here?

[R1der-on-The-Storm]

1. get::LocForEndOfToken() . Computes the source location just past the end of the token at this source location.
2. rewriter.InsertText(styleCastExpr->getEndLoc().getLocOffset(1),")"); give us position right after (cast) and getEndLoc().getLocOffset(1) shifts this position by one to the right. If the variable declared in main has a name of two or more symbol and use rewriter.InsertText(styleCastExpr->getEndLoc().getLocOffset(1),")"); . like main we will get m)ain .
   3)rewriter.InsertTextAfterToken(styleCastExpr->getEndLoc(),")"); . If use this we will get the same position and output but different way.

[ElizJogar]

Please describe the difference between the use of getRParenLoc() and getSubExprAsWritten()->getBeginLoc().

[R1der-on-The-Storm]

getRParenLos() a special method of the CStyleCastExprclass, this method returns the position where the closing right bracket is located. An object of the CStyleCastExpr class is an indication of a node in the AST tree.
If call the getSubExprAsWritten() method, it will return the desired tree node, ignoring the auxiliary ImplicitCastExpr nodes.
getBeginLoc() is used here to get the start position of this variable. But need to separately call the method of removing the closing right bracket rewriter_.Remove Text(styleCastExpr->getRParenLoc(), 1); .
The main difference is that when using getRParenLoc(), the search for the desired position is carried out using a closing parenthesis, and when using getSubExprAsWritten(), it is carried out using a variable for which the CStyleCast transformation was called.

[ElizJogar]

• How to prevent changing the C style cast code in macros?
• How to prevent changing the C style cast code for a special case - when we want to suppress warnings about unused variables?
• How to prevent parentheses from being added if they are already present in the (int)(f) code?

[ElizJogar]

What if StyleCastExpr is a null pointer? How to protect the program from crashing in such cases?

[R1der-on-The-Storm]

add this if(StyleCastExpr==nullptr) { return; }

[R1der-on-The-Storm]

How to prevent changing the C style cast code for a special case - when we want to suppress warnings about unused variables?
Need to check if(styleCastExpr->getCastKind() == CK_To Void) and if it is successful, do not cast.

[R1der-on-The-Storm]

How to prevent parentheses from being added if they are already present in the (int)(f) code?
like that
auto rangeVariable = Lexer::getSourceText(CharSourceRange::getTokenRange(
StyleCastExpr->getRParenLoc().getLocWithOffset(1),
StyleCastExpr->getEndLoc()),
*Result.SourceManager,
LangOptions()).str();
auto originalSize = rangeVariable.size();
rangeVariable.erase(
remove_if(
rangeVariable.begin(),
rangeVariable.end(),
[](char symbol) { return symbol == ' '; }),
rangeVariable.end());

    if (rangeVariable.front() != '(' && rangeVariable.back() != ')') {
    	rewriter.ReplaceText(rParenLoc.getLocWithOffset(1), originalSize, "(" + rangeVariable + ")");
    } else {
    	rewriter.ReplaceText(rParenLoc.getLocWithOffset(1), originalSize, rangeVariable);
    }

[R1der-on-The-Storm]

How to prevent changing the C style cast code in macros?
like that
if(CExpression->getExprLoc().isMacroID()) { return;}