This commit modernizes Go usage. This was done with:
go run golang.org/x/tools/gopls/internal/analysis/modernize/cmd/modernize@latest -fix -test ./...
Then files needed to be `go fmt`ed and a few comments needed to be
restored.
The modernizations include replacing
- if/else conditional assignment by a call to the built-in min or max functions added in go1.21
- sort.Slice(x, func(i, j int) bool) { return s[i] < s[j] } by a call to slices.Sort(s), added in go1.21
- interface{} by the 'any' type added in go1.18
- append([]T(nil), s...) by slices.Clone(s) or slices.Concat(s), added in go1.21
- loop around an m[k]=v map update by a call to one of the Collect, Copy, Clone, or Insert functions from the maps package, added in go1.21
- []byte(fmt.Sprintf...) by fmt.Appendf(nil, ...), added in go1.19
- append(s[:i], s[i+1]...) by slices.Delete(s, i, i+1), added in go1.21
- a 3-clause for i := 0; i < n; i++ {} loop by for i := range n {}, added in go1.22
After the config re-organisation, the setting of stringArray config
values (eg `--exclude` set with `RCLONE_EXCLUDE`) was broken and gave
a message like this for `RCLONE_EXCLUDE=*.jpg`:
Failed to load "filter" default values: failed to initialise "filter" options:
couldn't parse config item "exclude" = "*.jpg" as []string: parsing "*.jpg" as []string failed:
invalid character '/' looking for beginning of value
This was caused by the parser trying to parse the input string as a
JSON value.
When the config was re-organised it was thought that the internal
representation of stringArray values was not important as it was never
visible externally, however this turned out not to be true.
A defined representation was chosen - a comma separated string and
this was documented and tests were introduced in this patch.
This potentially introduces a very small backwards incompatibility. In
rclone v1.67.0
RCLONE_EXCLUDE=a,b
Would be interpreted as
--exclude "a,b"
Whereas this new code will interpret it as
--exclude "a" --exclude "b"
The benefit of being able to set multiple values with an environment
variable was deemed to outweigh the very small backwards compatibility
risk.
If a value with a `,` is needed, then use CSV escaping, eg
RCLONE_EXCLUDE="a,b"
(Note this needs to have the quotes in so at the unix shell that would be
RCLONE_EXCLUDE='"a,b"'
Fixes#8063
Apparently fmt.Sscanln doesn't parse bool's properly and this isn't
likely to be fixed by the Go team who regard sscanf as a mistake.
This only uses sscan for integers and uses the correct routine for
everything else.
This also implements parsing time.Duration
See: https://github.com/golang/go/issues/43306