Ranked Edges File KSP Order

[mitchwagner]

Problem:
Rows in the output file for paths have a column "KSP index" corresponding to the order the path was found. Rows in the ranked edges file have a corresponding column, referring to the index of the first path the edge was seen in. At first blush, one might be tempted to treat this as a rank for paths/edges.

However, the KSP index of these paths thus depends on implementation-dependent priorities that determine the orders paths of equal weight are found in, rather than the presumed path-weight ranking criteria. Two paths with the same weight will not receive the same KSP index.

This serves to make the ranked-edges file and to some extent the output file for paths counterintuitive, as they discriminate between edges/paths on arbitrary criteria.

Expected behavior:

• The output file listing paths should give the same KSP index to paths with the same rank
• The output file listing edges should otherwise remain unchanged, with the KSP index of the edge referring to the updated, implementation-agnostic index of the path

Reproduce:
This can be seen in our sample output files

This is not a bug, but I do think it violates the principle of least astonishment.