debian-packaging: Rework lexical compares to avoid sorting #11
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Sorting the entire character array isn't actually what the deb-version spec implies, and it breaks a variety of version comparisons. In particular, the function used to sort the character array needs to return Equal on two letters to preserve order, but that breaks comparisons between those letters, e.g. this currently returns Greater: ``` $ dpkg --compare-versions 1a lt 1b; echo $? 0 ``` However, fixing that means that strings with symbols can end up being sorted *before* letters: ``` $ dpkg --compare-versions 1b lt 1+a; echo $? 0 ``` This currently only compares properly by accident; the character sorting results in these two arrays: ``` ['b'] ['a', '+'] ``` and fixing the letter comparisons breaks this. This instead merges compare_char in with the main comparison loop (their logic already overlapped a bit) and removes the separate sorting step entirely. Signed-off-by: Ryan Gonzalez <ryan.gonzalez@collabora.com>
indygreg
approved these changes
Aug 13, 2023
No issues here, I can just point to the git repo for now. |
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Sorting the entire character array isn't actually what the deb-version spec implies, and it breaks a variety of version comparisons. In particular, the function used to sort the character array needs to return Equal on two letters to preserve order, but that breaks comparisons between those letters, e.g. this currently returns Greater:
However, fixing that means that strings with symbols can end up being sorted before letters:
This currently only compares properly by accident; the character sorting results in these two arrays:
and fixing the letter comparisons breaks this.
This instead merges compare_char in with the main comparison loop (their logic already overlapped a bit) and removes the separate sorting step entirely.