Clang Formatter ignore special comment indentation

[drkhodakarami]

Hi
I'm using clang formatter for vs code, There are two possible scenarios that can be added to formatter and they will help lots of people.

1- Lets say that I have something like this //--- anything after......
In this case, any comment that starts with ---, I prefer to be untouched and ignored for indentation and alignment by formatter.

2- Comments starting at column number 0 : Again, any comment that starts at column number 0 should be ignored by formatter.

these two can become available by some option in the .clong-format file like this :
CommentIgnor: "---"
CommentIgnoreColumnZero: true

Please add these two options. I believe that many people have asked for one or both of these in different places on web.

[llvmbot]

@llvm/issue-subscribers-clang-format

Author: Alireza Khodakarami (drkhodakarami)

Hi I'm using clang formatter for vs code, There are two possible scenarios that can be added to formatter and they will help lots of people.

1- Lets say that I have something like this //--- anything after......
In this case, any comment that starts with ---, I prefer to be untouched and ignored for indentation and alignment by formatter.

2- Comments starting at column number 0 : Again, any comment that starts at column number 0 should be ignored by formatter.

these two can become available by some option in the .clong-format file like this :
CommentIgnor: "---"
CommentIgnoreColumnZero: true

Please add these two options. I believe that many people have asked for one or both of these in different places on web.

[oblivioncth]

I imagine something a little more sophisticated that exactly what the OP mentioned might be desirable, like some formal recognition (and configuration of) heading comments, and options that specify they are to be left alone, aligned with the block/declarations that follow, always be moved to position 0, etc. However, what they mentioned would still be better than nothing.

To add a concrete example, I like to organize the contents of my classes, using a specific format of comment for that:

class QX_CORE_EXPORT IError
{
    friend class Error;
//-Class Variables----------------------------------------------------------------------------------------------------------
private:
    static inline const QString T_CODE_DUPE = u"Error type code %1 is already claimed by %2!"_s;
    static inline const QString T_NAME_DUPE = u"Error type name %1 is already claimed!"_s;
    static inline const QString T_CODE_RESERVED = u"Error type code %1 is reserved!"_s;
    static inline constinit QHash<quint16, const QString*> codeRegistry;

//-Class Functions----------------------------------------------------------------------------------------------------------
private:
    static QSet<QString>& nameRegistry(); // RAII

protected:
    static bool registerType(quint16 tc, const QString& tn);

//-Constructor--------------------------------------------------------------------------------------------------------------
protected:
    IError() = default;

//-Instance Functions-------------------------------------------------------------------------------------------------------
protected:
    virtual quint32 deriveValue() const;
    virtual Severity deriveSeverity() const;
    virtual QString deriveCaption() const;
    virtual QString derivePrimary() const;
    virtual QString deriveSecondary() const;
    virtual QString deriveDetails() const;

//-Operators-----------------------------------------------------------------------------------------------------------------
public:
    bool operator==(const IError& other) const = default;
    bool operator!=(const IError& other) const = default;
};

I need these to stay aligned with the class keyword/braces, but clang-format insists on indenting them to match the rest of the class body:

class QX_CORE_EXPORT IError
{
    friend class Error;
    //-Class Variables----------------------------------------------------------------------------------------------------------
private:
    static inline const QString T_CODE_DUPE = u"Error type code %1 is already claimed by %2!"_s;
...

I was hoping this could be worked around using CommentPragmas, but that doesn't prevent indentation.

[jshofmann]

+1 on the 'Comments starting at column number 0 : Again, any comment that starts at column number 0 should be ignored by formatter.' bit. Our code base has a lot of debug and diagnostic printouts that remain commented out, and having clang-format modify them is a significant impediment to our use of clang-format.

Alternatively, if clang-format could have an 'Ignore Comments' mode where it just leaves all comments untouched, that would be great too. That is, using the C++ comment token as an example here, it won't touch anything after a // until the end of the line. It can modify anything before the // but won't modify or reflow anything after the //. If the // is in column zero that's behavior equivalent to point 2 above, or if there's whitespace before the comment that whitespace will be left alone (optionally perhaps?); if the comment is inline with code the code will be processed normally and then clang-format's work will end with the //.

[owenca]

Most of the feature requests here have been addressed by the new OneLineFormatOffRegex option.