Fix zsh completion scripts

[zhsj]

What type of PR is this?

(REQUIRED)

• bug
• cleanup
• documentation
• feature

What this PR does / why we need it:

(REQUIRED)

This fix completion when argument startswith -
And prevent completing a space when no candidates

Which issue(s) this PR fixes:

(REQUIRED)

Release Notes

(REQUIRED)

Fix zsh completion scripts

[codecov]

Codecov Report

Merging #1062 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1062   +/-   ##
=======================================
  Coverage   72.83%   72.83%           
=======================================
  Files          33       33           
  Lines        2474     2474           
=======================================
  Hits         1802     1802           
  Misses        565      565           
  Partials      107      107

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[rliebz]

Thanks for the fix!

Would you mind providing examples of what was broken before and what's changed? Between the PR description and the code changed, I'm having trouble understanding what exactly the issue was.

[zhsj]

Thanks for fix!

Would you mind providing examples of what was broken before and what's changed? Between the PR description and the code changed, I'm having trouble understanding what exactly the issue was.

Before the change, if you type command -<tab> in zsh, nothing happens. With this change, it will display the candicates(eg -h).

The problem here is the words variable, when type <tab> before -, the last word is -, not "".

The change is based on the code of bash completion script,

cli/autocomplete/bash_autocomplete

Lines 10 to 14 in cc46cf9

	if [[ "$cur" == "-"* ]]; then
	opts=$( ${COMP_WORDS[@]:0:$COMP_CWORD} ${cur} --generate-bash-completion )
	else
	opts=$( ${COMP_WORDS[@]:0:$COMP_CWORD} --generate-bash-completion )
	fi