Differential D14247
Prevent exponential explosion of text-mode rendering of deeply nested blockquotes Authored by epriestley on Oct 8 2015, 8:59 PM. Tags None Referenced Files
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Details Currently, the text-mode rendering of blockquotes doubles the number of lines in the input text. For example, a deeply nested input text like this: >>>> a >>>> b ...gets expanded to: > a > b ...then to: > > a > > > b > ...and so on. If you nest something 28 levels deep, we generate 60 million lines from it. So:
Special thanks to @csilvers for hunting this down. Added a unit test. Generated mail for >>>>>>>>>>>>>>>>>>>>>>>>>>> REQUESTING CHANGES BECAUSE I'M ANGRY!.
Diff Detail
Event TimelineComment Actions I'm not really understanding what's going on here -- I guess this function must be being called once per level of > seen?, though I don't see where any doubling happens -- but thanks for fixing it up! Comment Actions The doubling is because $lines retains newlines (phutil_split_lines() is newline-preserving by default), and then we add extra newlines by imploding with "\n". Every level basically applies the rule \n -> \n\n> So we get: \n \n\n> \n\n>\n\n>> \n\n>\n\n>>\n\n>\n\n>>> \n\n>\n\n>\n\n>\n\n>>>\n\n>\n\n>>\n\n>\n\n>>>> Comment Actions ____________
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