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
This is possible now that we no longer support go1.12 and brings
rclone into line with standard practices in the Go world.
This also removes errors.New and errors.Errorf from lib/errors and
prefers the stdlib errors package over lib/errors.
Nick Craig-Wood
Fabian Möller