tree 284797c9690bb17dfdaa476d8bb4636a02659aca
parent 0846b9324399ff782fcc38e0c156f418910b361c
author Grant Zvolsky <grant@zvolsky.org> 1581275585 +0100
committer Marcel van Lohuizen <mpvl@golang.org> 1581967302 +0000

cmd/cue/cmd: prevent infinite loops while building dependency graph

The existing implementatin resulted in an infinite loop in two cases:

1. In the v.Equals(after) call when the 'after' dependencies were cyclic
2. In the task.Walk function when task fields cyclically referenced
other tasks

This commit solves both cases by
- stepping out of the Walk lambda when it had already been evaluated
with the given parameter; and
- removing the special case for 'after' dependencies as it is no longer
necessary.

Relevent tests are included.

Updates #245

Change-Id: I914ff9aad96eb43ae89964000dea60ccd44c38a2
Reviewed-on: https://cue-review.googlesource.com/c/cue/+/4910
Reviewed-by: Marcel van Lohuizen <mpvl@golang.org>