Commit d4ad4a25 slowed loading of completion.bash significantly (on my
laptop from 10 ms to 30 ms), then 54891d11 improved that (to 20 ms) but
it still stands out as the heavy part of my .bashrc.
Rewriting __fzf_orig_completion_filter to pure bash without forking to
sed/awk brings this back under 10 ms.
before:
$ HISTFILE=/tmp/bashhist hyperfine 'bash --rcfile shell/completion.bash -i'
Benchmark #1: bash --rcfile shell/completion.bash -i
Time (mean ± σ): 21.2 ms ± 0.3 ms [User: 24.9 ms, System: 6.4 ms]
Range (min … max): 20.7 ms … 23.3 ms 132 runs
after:
$ HISTFILE=/tmp/bashhist hyperfine 'bash --rcfile shell/completion.bash -i'
Benchmark #1: bash --rcfile shell/completion.bash -i
Time (mean ± σ): 9.6 ms ± 0.3 ms [User: 8.0 ms, System: 2.2 ms]
Range (min … max): 9.3 ms … 11.4 ms 298 runs
Fixes: d4ad4a25db ("[bash-completion] Fix default alias/variable completion")
Fixes: 54891d11e0 ("[bash-completion] Minor optimization")
This prevents mistakes like the one fixed by the previous commit, and
also speeds bash startup a tiny bit:
before:
$ HISTFILE=/tmp/bashhist hyperfine 'bash --rcfile shell/completion.bash -i'
Benchmark #1: bash --rcfile shell/completion.bash -i
Time (mean ± σ): 22.4 ms ± 0.6 ms [User: 28.7 ms, System: 7.8 ms]
Range (min … max): 21.7 ms … 25.2 ms 123 runs
after:
$ HISTFILE=/tmp/bashhist hyperfine 'bash --rcfile shell/completion.bash -i'
Benchmark #1: bash --rcfile shell/completion.bash -i
Time (mean ± σ): 21.2 ms ± 0.3 ms [User: 24.9 ms, System: 6.4 ms]
Range (min … max): 20.7 ms … 23.3 ms 132 runs
This doesn't look right:
$ complete | grep ' _.$'
complete _a
complete _v
The __fzf_orig_completion_filter invocation in _fzf_setup_completion
needs the /-F/ filter, just like all the other invocations.
Fixes: d4ad4a25db ("[bash-completion] Fix default alias/variable completion")
The output may contain some unexpected warning messages from the shell
if it's not properly configured. While such extra messages should be
properly addressed by the user, we can ignore them by checking the
last line of the output instead of the first line.
Related: bd3a021ec1
Fix#2212
# Will start rendering after 200ms, update every 100ms
fzf --preview 'for i in $(seq 100); do echo $i; sleep 0.01; done'
# Should print "Loading .." message after 500ms
fzf --preview 'sleep 1; for i in $(seq 100); do echo $i; sleep 0.01; done'
# The first line should appear after 200ms
fzf --preview 'date; sleep 2; date'
# Should not render before enough lines for the scroll offset are ready
rg --line-number --no-heading --color=always ^ |
fzf --delimiter : --ansi --preview-window '+{2}-/2' \
--preview 'sleep 1; bat --style=numbers --color=always --pager=never --highlight-line={2} {1}'