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@BasPH
Created December 11, 2018 19:53
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Black on selection
#!/usr/bin/env bash
set -x
black=$1
input_file=$2
start_line=$3
end_line=$4
# Read selected lines and write to tmpfile
selection=$(sed -n "$start_line, $end_line p; $(($end_line+1)) q" < $input_file)
tmpfile=$(mktemp)
echo "$selection" > "$tmpfile"
# Apply Black formatting to tmpfile
$black $tmpfile
# Delete original lines from file
sed -i "" "$start_line,$end_line d" $input_file
# And insert newly formatted lines
sed -i "" "$(($start_line-1)) r $tmpfile" $input_file
@valaparthvi
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You are a saviour @BasPH ! I found your article on partial formatting with Black and it was very helpful! I guess I'll finally start using Pycharm after this.

@imcomking
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imcomking commented Feb 4, 2020

Hello, I really appreciate for your cool and nice work!

I made a python version to utilize your 'partial black" in Windows OS and complied it to exe.
https://gist.github.com/imcomking/04d8ce30b6ac444e413392ab675b1d2c

@mrezzamoradi
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Great script! thank you @BasPH

By the way < $input_file part in line 11 is missing in the script in your post.

@GitHK
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GitHK commented Apr 16, 2020

thanks for the script. it's a lifesaver

@josebama
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Really cool, it's exactly what I was looking for.

I think it would be good to also add set -e to the script so that if black fails, we don't risk overwriting anything

@levsa
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levsa commented May 7, 2020

I think the deletion of the original lines deletes one extra line. It should delete until "$end_line - 1"

@nauman-chaudhary
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Any idea about this? @BasPH

error: cannot format /var/folders/bf/5_lvbmr539v26pk7qbrdrnd5drn_gd/T/tmp.8S3OqTW5: cannot use --safe with this file; failed to parse source file AST: unexpected indent (<unknown>, line 1)
This could be caused by running Black with an older Python version that does not support new syntax used in your source file.

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