The Cobra generated PowerShell completion script captures rclone's output
through a pipeline with Invoke-Expression. PowerShell decodes that output
using [Console]::OutputEncoding, which on non-UTF-8 hosts (for example
PowerShell 5.1 on a Windows install with an OEM code page such as CP852)
misinterprets the UTF-8 bytes rclone emits and corrupts remote and path
names containing non-ASCII characters, so tab completion produces a path
that does not exist.
Inject "[Console]::OutputEncoding = [System.Text.Encoding]::UTF8" into the
generated script immediately before the Invoke-Expression call. This is safe
on PowerShell 7+, where UTF-8 is already the default. If the expected line is
not present (for example after a Cobra template change) the script is emitted
unmodified so we never produce a corrupted completion script.
This changes log statements from log to fs package, which is required for --use-json-log
to properly make log output in JSON format. The recently added custom linting rule,
handled by ruleguard via gocritic via golangci-lint, warns about these and suggests
the alternative. Fixing was therefore basically running "golangci-lint run --fix",
although some manual fixup of mainly imports are necessary following that.