REXML wrapping and rcov
I recently ran in to some problems trying to get Rcov to run on a new code base I’m working with. Admittedtly a few of the files are far longer that I’d like, but a standard xml library should deal with such things gracefully. Unfortunately, REXML will throw all sorts of nastiness on pretty.rb:131. The problem is that the wrap function: a) doesn’t handle a few corner cases when spaces show up in weird spots, and b) since its a tail-recursive function if the string is long enough the interpreter will throw a Stack-level too deep error.
Fortunately the corner cases can be dealt with and as we all know tail-recursion can be eliminated and converted to a loop quite easily. The patch looks like this (I’ll try and package it up properly at some point as a patch to core):
def wrap(string, width)
out = nil
# Recursively wrap string at width.
while true
return [out, string].compact.join("\n") if string.length <= width
place = string.rindex(' ', width) # Position in string with last ' ' before cutoff
start = 0
if place.nil? || place == 0
start = width
place = width
else
start = place + 1
end
out = [out, string[0,place]].compact.join("\n")
string = string[start..-1]
end
end
