This would have addressed a recent issue that arose when re-ordering our
"filesystem layers". Specifically moving the caseFilesystem to the
outermost layer. The previous cache included the filesystem, and as such
all the layers below. This isn't desirable (to put it mildly), as you
can create different variants of filesystems with different layers for
the same path and options. Concretely this did happen with the mtime
layer, which isn't always present. A test for the mtime related breakage
was added in #9687, and I intend to redo the caseFilesystem reordering
after this.
Ref: #9677
Followup to: #9687
The test is quite odd and specific, but it does reproduce the issue that
caused #9677, so I'd propose to add it to have a simple regression test
for the basic scenario. Also the option to the fakefs might come handy
for other scenarios where you want to quickly test some behaviour on a
filesystem without nanosecond precision, without actually needing access
to one.
all: Add package runtimeos for runtime.GOOS comparisons
I grew tired of hand written string comparisons. This adds generated
constants for the GOOS values, and predefined Is$OS constants that can
be iffed on. In a couple of places I rewrote trivial switch:es to if:s,
and added Illumos where we checked for Solaris (because they are
effectively the same, and if we're going to target one of them that
would be Illumos...).
