pystring.h

// Copyright Contributors to the Pystring project.
// SPDX-License-Identifier: BSD-3-Clause
// https://github.com/imageworks/pystring/blob/master/LICENSE


#ifndef INCLUDED_PYSTRING_H
#define INCLUDED_PYSTRING_H

#include <string>
#include <vector>

namespace pystring
{

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @mainpage pystring
    ///
    /// This is a set of functions matching the interface and behaviors of python string methods
    /// (as of python 2.3) using std::string.
    ///
    /// Overlapping functionality ( such as index and slice/substr ) of std::string is included
    /// to match python interfaces.
    ///

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @defgroup functions pystring
    /// @{


    #define MAX_32BIT_INT 2147483647

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string with only its first character capitalized.
    ///
    std::string capitalize( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return centered in a string of length width. Padding is done using spaces.
    ///
    std::string center( const std::string & str, int width );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the number of occurrences of substring sub in string S[start:end]. Optional
    /// arguments start and end are interpreted as in slice notation.
    ///
    int count( const std::string & str, const std::string & substr, int start = 0, int end = MAX_32BIT_INT);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return True if the string ends with the specified suffix, otherwise return False. With
    /// optional start, test beginning at that position. With optional end, stop comparing at that position.
    ///
    bool endswith( const std::string & str, const std::string & suffix, int start = 0, int end = MAX_32BIT_INT );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string where all tab characters are expanded using spaces. If tabsize
    /// is not given, a tab size of 8 characters is assumed.
    ///
    std::string expandtabs( const std::string & str, int tabsize = 8);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the lowest index in the string where substring sub is found, such that sub is
    /// contained in the range [start, end). Optional arguments start and end are interpreted as
    /// in slice notation. Return -1 if sub is not found.
    ///
    int find( const std::string & str, const std::string & sub, int start = 0, int end = MAX_32BIT_INT  );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Synonym of find right now. Python version throws exceptions. This one currently doesn't
    ///
    int index( const std::string & str, const std::string & sub, int start = 0, int end = MAX_32BIT_INT  );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return true if all characters in the string are alphanumeric and there is at least one
    /// character, false otherwise.
    ///
    bool isalnum( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return true if all characters in the string are alphabetic and there is at least one
    /// character, false otherwise
    ///
    bool isalpha( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return true if all characters in the string are digits and there is at least one
    /// character, false otherwise.
    ///
    bool isdigit( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return true if all cased characters in the string are lowercase and there is at least one
    /// cased character, false otherwise.
    ///
    bool islower( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return true if there are only whitespace characters in the string and there is at least
    /// one character, false otherwise.
    ///
    bool isspace( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return true if the string is a titlecased string and there is at least one character,
    /// i.e. uppercase characters may only follow uncased characters and lowercase characters only
    /// cased ones. Return false otherwise.
    ///
    bool istitle( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return true if all cased characters in the string are uppercase and there is at least one
    /// cased character, false otherwise.
    ///
    bool isupper( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a string which is the concatenation of the strings in the sequence seq.
    /// The separator between elements is the str argument
    ///
    std::string join( const std::string & str, const std::vector< std::string > & seq );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the string left justified in a string of length width. Padding is done using
    /// spaces. The original string is returned if width is less than str.size().
    ///
    std::string ljust( const std::string & str, int width );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string converted to lowercase.
    ///
    std::string lower( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string with leading characters removed. If chars is omitted or None,
    /// whitespace characters are removed. If given and not "", chars must be a string; the
    /// characters in the string will be stripped from the beginning of the string this method
    /// is called on (argument "str" ).
    ///
    std::string lstrip( const std::string & str, const std::string & chars = "" );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string, concatenated N times, together.
    /// Corresponds to the __mul__ operator.
    /// 
    std::string mul( const std::string & str, int n);
    
    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Split the string around first occurance of sep.
    /// Three strings will always placed into result. If sep is found, the strings will
    /// be the text before sep, sep itself, and the remaining text. If sep is
    /// not found, the original string will be returned with two empty strings.
    ///
    void partition( const std::string & str, const std::string & sep, std::vector< std::string > & result );
    inline std::vector< std::string > partition( const std::string & str, const std::string & sep )
    {
        std::vector< std::string > result;
        partition( str, sep, result );
        return result;
    }

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string with all occurrences of substring old replaced by new. If
    /// the optional argument count is given, only the first count occurrences are replaced.
    ///
    std::string replace( const std::string & str, const std::string & oldstr, const std::string & newstr, int count = -1);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the highest index in the string where substring sub is found, such that sub is
    /// contained within s[start,end]. Optional arguments start and end are interpreted as in
    /// slice notation. Return -1 on failure.
    ///
    int rfind( const std::string & str, const std::string & sub, int start = 0, int end = MAX_32BIT_INT );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Currently a synonym of rfind. The python version raises exceptions. This one currently
    /// does not
    ///
    int rindex( const std::string & str, const std::string & sub, int start = 0, int end = MAX_32BIT_INT );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the string right justified in a string of length width. Padding is done using
    /// spaces. The original string is returned if width is less than str.size().
    ///
    std::string rjust( const std::string & str, int width);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Split the string around last occurance of sep.
    /// Three strings will always placed into result. If sep is found, the strings will
    /// be the text before sep, sep itself, and the remaining text. If sep is
    /// not found, the original string will be returned with two empty strings.
    ///
    void rpartition( const std::string & str, const std::string & sep, std::vector< std::string > & result );
    inline std::vector< std::string > rpartition ( const std::string & str, const std::string & sep )
    {
        std::vector< std::string > result;
        rpartition( str, sep, result );
        return result;
    }

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string with trailing characters removed. If chars is "", whitespace
    /// characters are removed. If not "", the characters in the string will be stripped from the
    /// end of the string this method is called on.
    ///
    std::string rstrip( const std::string & str, const std::string & chars = "" );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Fills the "result" list with the words in the string, using sep as the delimiter string.
    /// If maxsplit is > -1, at most maxsplit splits are done. If sep is "",
    /// any whitespace string is a separator.
    ///
    void split( const std::string & str, std::vector< std::string > & result, const std::string & sep = "", int maxsplit = -1);
    inline std::vector< std::string > split( const std::string & str, const std::string & sep = "", int maxsplit = -1)
    {
        std::vector< std::string >  result;
        split( str, result, sep, maxsplit );
        return result;
    }

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Fills the "result" list with the words in the string, using sep as the delimiter string.
    /// Does a number of splits starting at the end of the string, the result still has the
    /// split strings in their original order.
    /// If maxsplit is > -1, at most maxsplit splits are done. If sep is "",
    /// any whitespace string is a separator.
    ///
    void rsplit( const std::string & str, std::vector< std::string > & result, const std::string & sep = "", int maxsplit = -1);
    inline std::vector< std::string > rsplit( const std::string & str, const std::string & sep = "", int maxsplit = -1)
    {
        std::vector< std::string > result;
        rsplit( str, result, sep, maxsplit);
        return result;
    }

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a list of the lines in the string, breaking at line boundaries. Line breaks
    /// are not included in the resulting list unless keepends is given and true.
    ///
    void splitlines(  const std::string & str, std::vector< std::string > & result, bool keepends = false );
    inline std::vector< std::string > splitlines(  const std::string & str, bool keepends = false )
    {
        std::vector< std::string > result;
        splitlines( str, result, keepends);
        return result;
    }

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return True if string starts with the prefix, otherwise return False. With optional start,
    /// test string beginning at that position. With optional end, stop comparing string at that
    /// position
    ///
    bool startswith( const std::string & str, const std::string & prefix, int start = 0, int end = MAX_32BIT_INT );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string with leading and trailing characters removed. If chars is "",
    /// whitespace characters are removed. If given not "",  the characters in the string will be
    /// stripped from the both ends of the string this method is called on.
    ///
    std::string strip( const std::string & str, const std::string & chars = "" );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string with uppercase characters converted to lowercase and vice versa.
    ///
    std::string swapcase( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a titlecased version of the string: words start with uppercase characters,
    /// all remaining cased characters are lowercase.
    ///
    std::string title( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string where all characters occurring in the optional argument
    /// deletechars are removed, and the remaining characters have been mapped through the given
    /// translation table, which must be a string of length 256.
    ///
    std::string translate( const std::string & str, const std::string & table, const std::string & deletechars = "");

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a copy of the string converted to uppercase.
    ///
    std::string upper( const std::string & str );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the numeric string left filled with zeros in a string of length width. The original
    /// string is returned if width is less than str.size().
    ///
    std::string zfill( const std::string & str, int width );

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief function matching python's slice functionality.
    ///
    std::string slice( const std::string & str, int start = 0, int end = MAX_32BIT_INT);

    ///
    /// @ }
    ///


namespace os
{
namespace path
{
    // All of the function below have three versions.
    // Example:
    //   join(...)
    //   join_nt(...)
    //   join_posix(...)
    //
    // The regular function dispatches to the other versions - based on the OS
    // at compile time - to match the result you'd get from the python
    // interepreter on the same operating system
    // 
    // Should you want to 'lock off' to a particular version of the string
    // manipulation across *all* operating systems, use the version with the
    // _OS you are interested in.  I.e., you can use posix style path joining,
    // even on Windows, with join_posix.
    //
    // The naming, (nt, posix) matches the cpython source implementation.
    
    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @defgroup functions pystring::os::path
    /// @{
    
    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the base name of pathname path. This is the second half of the pair returned
    /// by split(path). Note that the result of this function is different from the Unix basename
    /// program; where basename for '/foo/bar/' returns 'bar', the basename() function returns an
    /// empty string ('').
    
    std::string basename(const std::string & path);
    std::string basename_nt(const std::string & path);
    std::string basename_posix(const std::string & path);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return the directory name of pathname path. This is the first half of the pair
    /// returned by split(path).
    
    std::string dirname(const std::string & path);
    std::string dirname_nt(const std::string & path);
    std::string dirname_posix(const std::string & path);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return True if path is an absolute pathname. On Unix, that means it begins with a
    /// slash, on Windows that it begins with a (back)slash after chopping off a potential drive
    /// letter.

    bool isabs(const std::string & path);
    bool isabs_nt(const std::string & path);
    bool isabs_posix(const std::string & s);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Return a normalized absolutized version of the pathname path.
    /// 
    /// NOTE: This differs from the interface of the python equivalent in that it requires you
    /// to pass in the current working directory as an argument.
    
    std::string abspath(const std::string & path, const std::string & cwd);
    std::string abspath_nt(const std::string & path, const std::string & cwd);
    std::string abspath_posix(const std::string & path, const std::string & cwd);
    

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Join one or more path components intelligently. If any component is an absolute
    /// path, all previous components (on Windows, including the previous drive letter, if there
    /// was one) are thrown away, and joining continues. The return value is the concatenation of
    /// path1, and optionally path2, etc., with exactly one directory separator (os.sep) inserted
    /// between components, unless path2 is empty. Note that on Windows, since there is a current
    /// directory for each drive, os.path.join("c:", "foo") represents a path relative to the
    /// current directory on drive C: (c:foo), not c:\foo.
    
    /// This dispatches based on the compilation OS
    std::string join(const std::string & path1, const std::string & path2);
    std::string join_nt(const std::string & path1, const std::string & path2);
    std::string join_posix(const std::string & path1, const std::string & path2);
    
    std::string join(const std::vector< std::string > & paths);
    std::string join_nt(const std::vector< std::string > & paths);
    std::string join_posix(const std::vector< std::string > & paths);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Normalize a pathname. This collapses redundant separators and up-level references
    /// so that A//B, A/B/, A/./B and A/foo/../B all become A/B. It does not normalize the case
    /// (use normcase() for that). On Windows, it converts forward slashes to backward slashes.
    /// It should be understood that this may change the meaning of the path if it contains
    /// symbolic links!

    std::string normpath(const std::string & path);
    std::string normpath_nt(const std::string & path);
    std::string normpath_posix(const std::string & path);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Split the pathname path into a pair, (head, tail) where tail is the last pathname
    /// component and head is everything leading up to that. The tail part will never contain a
    /// slash; if path ends in a slash, tail will be empty. If there is no slash in path, head
    /// will be empty. If path is empty, both head and tail are empty. Trailing slashes are
    /// stripped from head unless it is the root (one or more slashes only). In all cases,
    /// join(head, tail) returns a path to the same location as path (but the strings may
    /// differ).

    void split(std::string & head, std::string & tail, const std::string & path);
    void split_nt(std::string & head, std::string & tail, const std::string & path);
    void split_posix(std::string & head, std::string & tail, const std::string & path);

    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Split the pathname path into a pair (drive, tail) where drive is either a drive
    /// specification or the empty string. On systems which do not use drive specifications,
    /// drive will always be the empty string. In all cases, drive + tail will be the same as
    /// path.
    
    void splitdrive(std::string & drivespec, std::string & pathspec, const std::string & path);
    void splitdrive_nt(std::string & drivespec, std::string & pathspec, const std::string & p);
    void splitdrive_posix(std::string & drivespec, std::string & pathspec, const std::string & path);
    
    //////////////////////////////////////////////////////////////////////////////////////////////
    /// @brief Split the pathname path into a pair (root, ext) such that root + ext == path, and
    /// ext is empty or begins with a period and contains at most one period. Leading periods on
    /// the basename are ignored; splitext('.cshrc') returns ('.cshrc', '').

    void splitext(std::string & root, std::string & ext, const std::string & path);
    void splitext_nt(std::string & root, std::string & ext, const std::string & path);
    void splitext_posix(std::string & root, std::string & ext, const std::string & path);
    
    ///
    /// @ }
    ///
} // namespace path
} // namespace os

} // namespace pystring

#endif