diff options
Diffstat (limited to 'regexec.c')
| -rw-r--r-- | regexec.c | 48 |
1 files changed, 40 insertions, 8 deletions
@@ -4534,7 +4534,8 @@ S_isWB(pTHX_ WB_enum previous, const bool utf8_target) { /* Return a boolean as to if the boundary between 'before' and 'after' is - * a Unicode word break, using their published algorithm. Context may be + * a Unicode word break, using their published algorithm, but tailored for + * Perl by treating spans of white space as one unit. Context may be * needed to make this determination. If the value for the character * before 'before' is known, it is passed as 'previous'; otherwise that * should be set to WB_UNKNOWN. The other input parameters give the @@ -4552,17 +4553,48 @@ S_isWB(pTHX_ WB_enum previous, return TRUE; } - /* WB 3: Do not break within CRLF. */ - if (before == WB_CR && after == WB_LF) { - return FALSE; + /* WB 3 is: "Do not break within CRLF." Perl extends this so that all + * white space sequences ending in a vertical space are treated as one + * unit. */ + + if (after == WB_CR || after == WB_LF || after == WB_Newline) { + if (before == WB_CR || before == WB_LF || before == WB_Newline + || before == WB_Perl_Tailored_HSpace) + { + return FALSE; + } + + /* WB 3a: Otherwise break before Newlines (including CR and LF) */ + return TRUE; } - /* WB 3a and WB 3b: Otherwise break before and after Newlines (including CR - * and LF) */ + /* Here, we know that 'after' is not a vertical space character, but + * 'before' could be. WB 3b is: "Otherwise break after Newlines (including + * CR and LF)." Perl changes that to not break-up spans of white space, + * except when horizontal space is followed by an Extend or Format + * character. These apply just to the final white space character in the + * span, so it is broken away from the rest. (If the Extend or Format + * character follows a vertical space character, it is treated as beginning + * a line, and doesn't modify the preceeding character.) */ if ( before == WB_CR || before == WB_LF || before == WB_Newline - || after == WB_CR || after == WB_LF || after == WB_Newline) + || before == WB_Perl_Tailored_HSpace) { - return TRUE; + if (after == WB_Perl_Tailored_HSpace) { + U8 * temp_pos = (U8 *) curpos; + const WB_enum next + = advance_one_WB(&temp_pos, strend, utf8_target, + FALSE /* Don't skip Extend nor Format */ ); + return next == WB_Extend || next == WB_Format; + } + else if (before != WB_Perl_Tailored_HSpace) { + + /* Here, 'before' must be one of the vertical space characters, and + * after is not any type of white-space. Follow WB 3b. */ + return TRUE; + } + + /* Here, 'before' is horizontal space, and 'after' is not any kind of + * space. Normal rules apply */ } /* Ignore Format and Extend characters, except when they appear at the |