fish-shell/share/functions/__fish_print_help.fish
Kurtis Rader 54a76bb9e5 emit error message when test is given invalid int
This augments the previous change for issue #3346 by adding an error
message when an invalid integer is seen. This change is likely to be
controversial so I'm not going to squash it into the previous change.
2016-11-27 20:37:30 -08:00

104 lines
3.9 KiB
Fish

function __fish_print_help --description "Print help message for the specified fish function or builtin" --argument item
# special support for builtin_help_get()
set -l tty_width 0
if test "$item" = "--tty-width"
set tty_width $argv[2]
set item $argv[3]
end
if test "$item" = '.'
set item source
end
# Do nothing if the file does not exist
if not test -e "$__fish_datadir/man/man1/$item.1" -o -e "$__fish_datadir/man/man1/$item.1.gz"
return
end
set -l IFS \n\ \t
# Render help output, save output into the variable 'help'
set -l help
set -l cols
set -l rLL
if test "$tty_width" -gt 0
set cols $tty_width
else if command test -t 1
# We want to simulate `man`'s dynamic line length, because
# defaulting to 80 kind of sucks.
# Note: using `command test` instead of `test` because `test -t 1`
# doesn't seem to work right.
# Note: grab the size from the stdout terminal in case it's somehow
# different than the stdin of fish.
# use fd 3 to copy our stdout because we need to pipe the output of stty
begin
stty size 0<&3 | read __ cols
end 3<&1
end
if test -n "$cols"
set cols (math $cols - 4) # leave a bit of space on the right
set rLL -rLL=$cols[1]n
end
set -lx GROFF_TMAC_PATH $__fish_datadir/groff
if test -e "$__fish_datadir/man/man1/$item.1"
set help (nroff -c -man -mfish -t $rLL "$__fish_datadir/man/man1/$item.1" ^/dev/null)
else if test -e "$__fish_datadir/man/man1/$item.1.gz"
set help (gunzip -c "$__fish_datadir/man/man1/$item.1.gz" ^/dev/null | nroff -c -man -mfish -t $rLL ^/dev/null)
end
# The original implementation trimmed off the top 5 lines and bottom 3 lines
# from the nroff output. Perhaps that's reliable, but the magic numbers make
# me extremely nervous. Instead, let's just strip out any lines that start
# in the first column. "normal" manpages put all section headers in the first
# column, but fish manpages only leave NAME like that, which we want to trim
# away anyway.
#
# While we're at it, let's compress sequences of blank lines down to a single
# blank line, to duplicate the default behavior of `man`, or more accurately,
# the `-s` flag to `less` that `man` passes.
set -l state blank
for line in $help
# categorize the line
set -l line_type
switch $line
case ' *' \t\*
# starts with whitespace, check if it has non-whitespace
printf "%s\n" $line | read -l word __
if test -n $word
set line_type normal
else
# lines with just spaces probably shouldn't happen
# but let's consider them to be blank
set line_type blank
end
case ''
set line_type blank
case '*'
# not leading space, and not empty, so must contain a non-space
# in the first column. That makes it a header/footer.
set line_type meta
end
switch $state
case normal
switch $line_type
case normal
printf "%s\n" $line
case blank
set state blank
case meta
# skip it
end
case blank
switch $line_type
case normal
echo # print the blank line
printf "%s\n" $line
set state normal
case blank meta
# skip it
end
end
end | ul # post-process with `ul`, to interpret the old-style grotty escapes
echo # print a trailing blank line
end