[lldb] Fix (unintentional) recursion in CommandObjectRegexCommand #3989
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Jim noticed that the regex command is unintentionally recursive. Let's use the following command regex as an example: (lldb) com regex humm 's/([^ ]+) ([^ ]+)/p %1 %2 %1 %2/' If we call it with arguments foo bar, thing behave as expected: (lldb) humm foo bar (...) foo bar foo bar However, if we include %2 in the arguments, things break down: (lldb) humm fo%2o bar (...) fobaro bar fobaro bar The problem is that the implementation of the substitution is too naive. It substitutes the %1 token into the target template in place, then does the %2 substitution starting with the resultant string. So if the previous substitution introduced a %2 token, it would get processed in the second sweep, etc. This patch addresses the issue by walking the command once and substituting the % variables in place. (lldb) humm fo%2o bar (...) fo%2o bar fo%2o bar Furthermore, this patch also reports an error if not enough variables were provided and add support for substituting %0. rdar://81236994 Differential revision: https://reviews.llvm.org/D120101 (cherry picked from commit 2a6dbed)
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@swift-ci please test |
JDevlieghere
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Jim noticed that the regex command is unintentionally recursive. Let's
use the following command regex as an example:
(lldb) com regex humm 's/([^ ]+) ([^ ]+)/p %1 %2 %1 %2/'
If we call it with arguments foo bar, thing behave as expected:
(lldb) humm foo bar
(...)
foo bar foo bar
However, if we include %2 in the arguments, things break down:
(lldb) humm fo%2o bar
(...)
fobaro bar fobaro bar
The problem is that the implementation of the substitution is too naive.
It substitutes the %1 token into the target template in place, then does
the %2 substitution starting with the resultant string. So if the
previous substitution introduced a %2 token, it would get processed in
the second sweep, etc.
This patch addresses the issue by walking the command once and
substituting the % variables in place.
(lldb) humm fo%2o bar
(...)
fo%2o bar fo%2o bar
Furthermore, this patch also reports an error if not enough variables
were provided and add support for substituting %0.
rdar://81236994
Differential revision: https://reviews.llvm.org/D120101
(cherry picked from commit 2a6dbed)