Showing 27 of 27 total issues
Avoid deeply nested control flow statements. Open
if all([
act['status'] == 'completed'
and act['conclusion'] == 'success' for act in actions
]):
action = 'success'
Avoid commands that rely on user settings Open
%s/\s\+$//e
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Google VimScript Style Guide (Fragile)
Can't follow non-constant source. Use a directive to specify location. Open
source "$HOME/dotfiles/ubuntu/.pathrc"
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Can't follow non-constant source. Use a directive to specify location.
Problematic code:
. "$(find_install_dir)/lib.sh"
Correct code:
# shellcheck source=src/lib.sh
. "$(find_install_dir)/lib.sh"
Rationale:
ShellCheck is not able to include sourced files from paths that are determined at runtime. The file will not be read, potentially resulting in warnings about unassigned variables and similar.
Use a [[Directive]] to point shellcheck to a fixed location it can read instead.
Exceptions:
If you don't care that ShellCheck is unable to account for the file, specify # shellcheck source=/dev/null
.
Notice
Original content from the ShellCheck https://github.com/koalaman/shellcheck/wiki.
Use scriptencoding when multibyte char exists Open
set clipboard=unnamed
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:help :scriptencoding
Avoid commands that rely on user settings Open
:silent! %s#\($\n\s*\)\+\%$##
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Google VimScript Style Guide (Fragile)
In POSIX sh, 'source' in place of '.' is undefined. Open
source "$HOME/dotfiles/ubuntu/.pathrc"
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In POSIX sh, something is undefined.
You have declared that your script works with /bin/sh
, but you are using features that have undefined behavior according to the POSIX specification.
It may currently work for you, but it can or will fail on other OS, the same OS with different configurations, from different contexts (like initramfs/chroot), or in different versions of the same OS, including future updates to your current system.
Either declare that your script requires a specific shell like #!/bin/bash
or #!/bin/dash
, or rewrite the script in a portable way.
For help with rewrites, the Ubuntu wiki has a list of portability issues that broke people's #!/bin/sh
scripts when Ubuntu switched from Bash to Dash. See also Bashism on wooledge's wiki. ShellCheck may not warn about all these issues.
$'c-style-escapes'
bash, ksh:
a=$' \t\n'
POSIX:
a="$(printf '%b_' ' \t\n')"; a="${a%_}" # protect trailing \n
Want some good news? See http://austingroupbugs.net/view.php?id=249#c590.
$"msgid"
Bash:
echo $"foo $(bar) baz"
POSIX:
. gettext.sh # GNU Gettext sh library
# ...
barout=$(bar)
eval_gettext 'foo $barout baz' # See GNU Gettext doc for more info.
Or you can change them to normal double quotes so you go without gettext
.
Arithmetic for
loops
Bash:
for ((init; test; next)); do foo; done
POSIX:
: $((init))
while [ $((test)) -ne 0 ]; do foo; : $((next)); done
Arithmetic exponentiation
Bash:
printf "%s\n" "$(( 2**63 ))"
POSIX:
The POSIX standard does not allow for exponents. However, you can replicate them completely built-in using a POSIX compatible function. As an example, the pow
function from here.
pow () {
set "$1" "$2" 1
while [ "$2" -gt 0 ]; do
set "$1" $(($2-1)) $(($1*$3))
done
# %d = signed decimal, %u = unsigned decimal
# Either should overflow to 0
printf "%d\n" "$3"
}
To compare:
$ echo "$(( 2**62 ))"
4611686018427387904
$ pow 2 62
4611686018427387904
Alternatively, if you don't mind using an external program, you can use bc
. Be aware though: bash
and other programs may abide by a certain maximum integer that bc
does not (for bash
that's: 64-bit signed long int, failing back to 32-bit signed long int).
Example:
# Note the overflow that gives a negative number
$ echo "$(( 2**63 ))"
-9223372036854775808
# No such problem
$ echo 2^63 | bc
9223372036854775808
# 'bc' just keeps on going
$ echo 2^1280 | bc
20815864389328798163850480654728171077230524494533409610638224700807\
21611934672059602447888346464836968484322790856201558276713249664692\
98162798132113546415258482590187784406915463666993231671009459188410\
95379622423387354295096957733925002768876520583464697770622321657076\
83317005651120933244966378183760369413644440628104205339687097746591\
6057756101739472373801429441421111406337458176
standalone ((..))
Bash:
((a=c+d))
((d)) && echo d is true.
POSIX:
: $((a=c+d)) # discard the output of the arith expn with `:` command
[ $((d)) -ne 0 ] && echo d is true. # manually check non-zero => true
select
loops
It takes extra care over terminal columns to make select loop look like bash's, which generates a list with multiple items on one line, or like ls
.
It is, however, still possible to make a naive translation for select foo in bar baz; do eat; done
:
while
_i=0 _foo= foo=
for _name in bar baz; do echo "$((_i+=1))) $_name"; done
printf '$# '; read _foo
do
case _foo in 1) foo=bar;; 2) foo=baz;; *) continue;; esac
eat
done
Here-strings
Bash, ksh:
grep aaa <<< "$g"
POSIX:
# not exactly the same -- <<< adds a trailing \n if $g doesn't end with \n
printf '%s' "$g" | grep aaa
echo flags
See https://unix.stackexchange.com/tags/echo/info.
${var/pat/replacement}
Bash:
echo "${TERM/%-256*}"
POSIX:
echo "$TERM" | sed -e 's/-256.*$//g'
# Special case for this since we are matching the end:
echo "${TERM%-256*}"
printf %q
Bash:
printf '%q ' "$@"
POSIX:
# TODO: Interpret it back to printf escapes for hard-to-copy chars like \t?
# See also: http://git.savannah.gnu.org/cgit/libtool.git/tree/gl/build-aux/funclib.sh?id=c60e054#n1029
reuse_quote()(
for i; do
__i_quote=$(printf '%s\n' "$i" | sed -e "s/'/'\\\\''/g"; echo x)
printf "'%s'" "${__i_quote%x}"
done
)
reuse_quote "$@"
Exception
Depends on what your expected POSIX shell providers would use.
Notice
Original content from the ShellCheck https://github.com/koalaman/shellcheck/wiki.
Avoid commands that rely on user settings Open
normal 'yz<CR>
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Google VimScript Style Guide (Fragile)
First header should be a top level header Open
## Marked
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MD002 - First header should be a top level header
Tags: headers
Aliases: first-header-h1
Parameters: level (number; default 1)
This rule is triggered when the first header in the document isn't a h1 header:
## This isn't a H1 header
### Another header
The first header in the document should be a h1 header:
# Start with a H1 header
## Then use a H2 for subsections
Do not use a command that has unintended side effects Open
%s/\s\+$//e
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Google VimScript Style Guide (Dangerous)
Unordered list indentation Open
* Set `darkwake=8` to enable sleep
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MD007 - Unordered list indentation
Tags: bullet, ul, indentation
Aliases: ul-indent
Parameters: indent (number; default 2)
This rule is triggered when list items are not indented by the configured number of spaces (default: 2).
Example:
* List item
* Nested list item indented by 3 spaces
Corrected Example:
* List item
* Nested list item indented by 2 spaces
Rationale (2 space indent): indenting by 2 spaces allows the content of a nested list to be in line with the start of the content of the parent list when a single space is used after the list marker.
Rationale (4 space indent): Same indent as code blocks, simpler for editors to implement. See http://www.cirosantilli.com/markdown-styleguide/#indented-lists for more information.
In addition, this is a compatibility issue with multi-markdown parsers, which require a 4 space indents. See http://support.markedapp.com/discussions/problems/21-sub-lists-not-indenting for a description of the problem.
Ordered list item prefix Open
2. Setup Miniconda
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MD029 - Ordered list item prefix
Tags: ol
Aliases: ol-prefix
Parameters: style ("one", "ordered"; default "one")
This rule is triggered on ordered lists that do not either start with '1.' or do not have a prefix that increases in numerical order (depending on the configured style, which defaults to 'one').
Example valid list if the style is configured as 'one':
1. Do this.
1. Do that.
1. Done.
Example valid list if the style is configured as 'ordered':
1. Do this.
2. Do that.
3. Done.
Avoid commands that rely on user settings Open
normal `z
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Google VimScript Style Guide (Fragile)
Avoid commands that rely on user settings Open
normal Hmy
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Google VimScript Style Guide (Fragile)
In POSIX sh, [[ ]] is undefined. Open
if [[ "$artist" != *"]"* ]]; then
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In POSIX sh, something is undefined.
You have declared that your script works with /bin/sh
, but you are using features that have undefined behavior according to the POSIX specification.
It may currently work for you, but it can or will fail on other OS, the same OS with different configurations, from different contexts (like initramfs/chroot), or in different versions of the same OS, including future updates to your current system.
Either declare that your script requires a specific shell like #!/bin/bash
or #!/bin/dash
, or rewrite the script in a portable way.
For help with rewrites, the Ubuntu wiki has a list of portability issues that broke people's #!/bin/sh
scripts when Ubuntu switched from Bash to Dash. See also Bashism on wooledge's wiki. ShellCheck may not warn about all these issues.
$'c-style-escapes'
bash, ksh:
a=$' \t\n'
POSIX:
a="$(printf '%b_' ' \t\n')"; a="${a%_}" # protect trailing \n
Want some good news? See http://austingroupbugs.net/view.php?id=249#c590.
$"msgid"
Bash:
echo $"foo $(bar) baz"
POSIX:
. gettext.sh # GNU Gettext sh library
# ...
barout=$(bar)
eval_gettext 'foo $barout baz' # See GNU Gettext doc for more info.
Or you can change them to normal double quotes so you go without gettext
.
Arithmetic for
loops
Bash:
for ((init; test; next)); do foo; done
POSIX:
: $((init))
while [ $((test)) -ne 0 ]; do foo; : $((next)); done
Arithmetic exponentiation
Bash:
printf "%s\n" "$(( 2**63 ))"
POSIX:
The POSIX standard does not allow for exponents. However, you can replicate them completely built-in using a POSIX compatible function. As an example, the pow
function from here.
pow () {
set "$1" "$2" 1
while [ "$2" -gt 0 ]; do
set "$1" $(($2-1)) $(($1*$3))
done
# %d = signed decimal, %u = unsigned decimal
# Either should overflow to 0
printf "%d\n" "$3"
}
To compare:
$ echo "$(( 2**62 ))"
4611686018427387904
$ pow 2 62
4611686018427387904
Alternatively, if you don't mind using an external program, you can use bc
. Be aware though: bash
and other programs may abide by a certain maximum integer that bc
does not (for bash
that's: 64-bit signed long int, failing back to 32-bit signed long int).
Example:
# Note the overflow that gives a negative number
$ echo "$(( 2**63 ))"
-9223372036854775808
# No such problem
$ echo 2^63 | bc
9223372036854775808
# 'bc' just keeps on going
$ echo 2^1280 | bc
20815864389328798163850480654728171077230524494533409610638224700807\
21611934672059602447888346464836968484322790856201558276713249664692\
98162798132113546415258482590187784406915463666993231671009459188410\
95379622423387354295096957733925002768876520583464697770622321657076\
83317005651120933244966378183760369413644440628104205339687097746591\
6057756101739472373801429441421111406337458176
standalone ((..))
Bash:
((a=c+d))
((d)) && echo d is true.
POSIX:
: $((a=c+d)) # discard the output of the arith expn with `:` command
[ $((d)) -ne 0 ] && echo d is true. # manually check non-zero => true
select
loops
It takes extra care over terminal columns to make select loop look like bash's, which generates a list with multiple items on one line, or like ls
.
It is, however, still possible to make a naive translation for select foo in bar baz; do eat; done
:
while
_i=0 _foo= foo=
for _name in bar baz; do echo "$((_i+=1))) $_name"; done
printf '$# '; read _foo
do
case _foo in 1) foo=bar;; 2) foo=baz;; *) continue;; esac
eat
done
Here-strings
Bash, ksh:
grep aaa <<< "$g"
POSIX:
# not exactly the same -- <<< adds a trailing \n if $g doesn't end with \n
printf '%s' "$g" | grep aaa
echo flags
See https://unix.stackexchange.com/tags/echo/info.
${var/pat/replacement}
Bash:
echo "${TERM/%-256*}"
POSIX:
echo "$TERM" | sed -e 's/-256.*$//g'
# Special case for this since we are matching the end:
echo "${TERM%-256*}"
printf %q
Bash:
printf '%q ' "$@"
POSIX:
# TODO: Interpret it back to printf escapes for hard-to-copy chars like \t?
# See also: http://git.savannah.gnu.org/cgit/libtool.git/tree/gl/build-aux/funclib.sh?id=c60e054#n1029
reuse_quote()(
for i; do
__i_quote=$(printf '%s\n' "$i" | sed -e "s/'/'\\\\''/g"; echo x)
printf "'%s'" "${__i_quote%x}"
done
)
reuse_quote "$@"
Exception
Depends on what your expected POSIX shell providers would use.
Notice
Original content from the ShellCheck https://github.com/koalaman/shellcheck/wiki.
E492: Not an editor command: packadd vim-happy-hacking Open
packadd vim-happy-hacking
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ynkdir/vim-vimlparser
Use scriptencoding when multibyte char exists Open
function! statusline#fileprefix() abort
- Read upRead up
- Exclude checks
:help :scriptencoding
Can't follow non-constant source. Use a directive to specify location. Open
source "$HOME/dotfiles/ubuntu/.pathrc"
- Read upRead up
- Exclude checks
Can't follow non-constant source. Use a directive to specify location.
Problematic code:
. "$(find_install_dir)/lib.sh"
Correct code:
# shellcheck source=src/lib.sh
. "$(find_install_dir)/lib.sh"
Rationale:
ShellCheck is not able to include sourced files from paths that are determined at runtime. The file will not be read, potentially resulting in warnings about unassigned variables and similar.
Use a [[Directive]] to point shellcheck to a fixed location it can read instead.
Exceptions:
If you don't care that ShellCheck is unable to account for the file, specify # shellcheck source=/dev/null
.
Notice
Original content from the ShellCheck https://github.com/koalaman/shellcheck/wiki.
Ordered list item prefix Open
5. Run `main.sh`
- Read upRead up
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MD029 - Ordered list item prefix
Tags: ol
Aliases: ol-prefix
Parameters: style ("one", "ordered"; default "one")
This rule is triggered on ordered lists that do not either start with '1.' or do not have a prefix that increases in numerical order (depending on the configured style, which defaults to 'one').
Example valid list if the style is configured as 'one':
1. Do this.
1. Do that.
1. Done.
Example valid list if the style is configured as 'ordered':
1. Do this.
2. Do that.
3. Done.
Use scriptencoding when multibyte char exists Open
set statusline= " Start with a clean line.
- Read upRead up
- Exclude checks
:help :scriptencoding
Avoid commands that rely on user settings Open
normal mz
- Read upRead up
- Exclude checks
Google VimScript Style Guide (Fragile)