[cmake-developers] [CMake 0014193]: get_filename_component(ABSOLUTE) doesn't remove multiple leading /

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://www.cmake.org/Bug/view.php?id=14193 
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Reported By:                Yichao Yu
Assigned To:                
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Project:                    CMake
Issue ID:                   14193
Category:                   CMake
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2013-06-04 01:54 EDT
Last Modified:              2013-06-04 01:54 EDT
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Summary:                    get_filename_component(ABSOLUTE) doesn't remove
multiple leading /
Description: 
When given a path with multiple leading /'s, get_filename_component returns a
filename with two leading /'s.
Although this behavior is consistent with how cd set PWD (see 8.c of cd(1)[1]),
it doesn't consistent with realpath(1) and realpath(3). And it also makes it
harder to use this absolute path as an unique identifier of the file directly.
Non-posix shell like zsh(1) also removes multiple leading /'s in PWD and I
personally don't see any advantage of not removing them.

The same thing applies to get_filename_component(REALPATH) when a not-yet-exists
path is given. (probably related to http://www.cmake.org/Bug/view.php?id=14192.)

[1] http://pubs.opengroup.org/onlinepubs/9699919799/utilities/cd.html


Steps to Reproduce: 
get_filename_component(abs_path "//lib" ABSOLUTE)
message("${abs_path}")

expected output:
/lib

actual output:
//lib

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Issue History 
Date Modified    Username       Field                    Change               
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2013-06-04 01:54 Yichao Yu      New Issue                                    
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