記錄一下 complete 各個引數含義。

-c 要補全的命令

-p 命令路徑

-e

-s 短引數 -h

-l 長引數 --help

-o old style long option

-a 新增子命令

-f 不列出檔案

-r

-x -f and -r

-w

-n 函式

-CSTRING

-C

-A

-u

-d 描述

    complete -- edit command specific tab-completions

Synopsis
    complete ( -c | --command | -p | --path ) COMMAND
            [( -c | --command | -p | --path ) COMMAND]...
            [( -e | --erase )]
            [( -s | --short-option ) SHORT_OPTION]...
            [( -l | --long-option | -o | --old-option ) LONG_OPTION]...
            [( -a | --arguments ) OPTION_ARGUMENTS]
            [( -f | --no-files )]
            [( -r | --require-parameter )]
            [( -x | --exclusive )]
            [( -w | --wraps ) WRAPPED_COMMAND]...
            [( -n | --condition ) CONDITION]
            [( -d | --description ) DESCRIPTION]
    complete ( -C[STRING] | --do-complete[=STRING] )

Description
    For an introduction to specifying completions, see Writing your own
    completions in the fish manual.

    · COMMAND is the name of the command for which to add a completion.

    · SHORT_OPTION is a one character option for the command.

    · LONG_OPTION is a multi character option for the command.

    · OPTION_ARGUMENTS is parameter containing a space-separated list of
      possible option-arguments, which may contain command substitutions.

    · DESCRIPTION is a description of what the option and/or option
      arguments do.

    · -c COMMAND or --command COMMAND specifies that COMMAND is the name
      of the command.

    · -p COMMAND or --path COMMAND specifies that COMMAND is the absolute
      path of the program (optionally containing wildcards).

    · -e or --erase deletes the specified completion.

    · -s SHORT_OPTION or --short-option=SHORT_OPTION adds a short option
      to the completions list.

    · -l LONG_OPTION or --long-option=LONG_OPTION adds a GNU style long
      option to the completions list.

    · -o LONG_OPTION or --old-option=LONG_OPTION adds an old style long
      option to the completions list (See below for details).

    · -a OPTION_ARGUMENTS or --arguments=OPTION_ARGUMENTS adds the
      specified option arguments to the completions list.

    · -f or --no-files specifies that the options specified by this
      completion may not be followed by a filename.

    · -r or --require-parameter specifies that the options specified by
      this completion always must have an option argument, i.e. may not
      be followed by another option.

    · -x or --exclusive implies both -r and -f.

    · -w WRAPPED_COMMAND or --wraps=WRAPPED_COMMAND causes the specified
      command to inherit completions from the wrapped command (See below
      for details).

    · -n or --condition specifies a shell command that must return 0 if
      the completion is to be used. This makes it possible to specify
      completions that should only be used in some cases.

    · -CSTRING or --do-complete=STRING makes complete try to find all
      possible completions for the specified string.

    · -C or --do-complete with no argument makes complete try to find all
      possible completions for the current command line buffer. If the
      shell is not in interactive mode, an error is returned.

    · -A and --authoritative no longer do anything and are silently
      ignored.

    · -u and --unauthoritative no longer do anything and are silently
      ignored.

    Command specific tab-completions in fish are based on the notion of
    options and arguments. An option is a parameter which begins with a
    hyphen, such as '-h', '-help' or '--help'. Arguments are parameters
    that do not begin with a hyphen. Fish recognizes three styles of
    options, the same styles as the GNU version of the getopt library.
    These styles are:

    · Short options, like '-a'. Short options are a single character
      long, are preceded by a single hyphen and may be grouped together
      (like '-la', which is equivalent to '-l -a'). Option arguments may
      be specified in the following parameter ('-w 32') or by appending
      the option with the value ('-w32').

    · Old style long options, like '-Wall'. Old style long options can be
      more than one character long, are preceded by a single hyphen and
      may not be grouped together. Option arguments are specified in the
      following parameter ('-ao null').

    · GNU style long options, like '--colors'. GNU style long options can
      be more than one character long, are preceded by two hyphens, and
      may not be grouped together. Option arguments may be specified in
      the following parameter ('--quoting-style shell') or by appending
      the option with a '=' and the value ('--quoting-style=shell'). GNU
      style long options may be abbreviated so long as the abbreviation
      is unique ('--h') is equivalent to '--help' if help is the only
      long option beginning with an 'h').

    The options for specifying command name and command path may be used
    multiple times to define the same completions for multiple commands.

    The options for specifying command switches and wrapped commands may
    be used multiple times to define multiple completions for the
    command(s) in a single call.

    Invoking complete multiple times for the same command adds the new
    definitions on top of any existing completions defined for the
    command.

    When -a or --arguments is specified in conjunction with long, short,
    or old style options, the specified arguments are only used as
    completions when attempting to complete an argument for any of the
    specified options. If -a or --arguments is specified without any
    long, short, or old style options, the specified arguments are used
    when completing any argument to the command (except when completing
    an option argument that was specified with -r or --require-
    parameter).

    Command substitutions found in OPTION_ARGUMENTS are not expected to
    return a space-separated list of arguments. Instead they must return
    a newline-separated list of arguments, and each argument may
    optionally have a tab character followed by the argument description.
    Any description provided in this way overrides a description given
    with -d or --description.

    The -w or --wraps options causes the specified command to inherit
    completions from another command. The inheriting command is said to
    'wrap' the inherited command. The wrapping command may have its own
    completions in addition to inherited ones. A command may wrap
    multiple commands, and wrapping is transitive: if A wraps B, and B
    wraps C, then A automatically inherits all of C's completions.
    Wrapping can be removed using the -e or --erase options. Note that
    wrapping only works for completions specified with -c or --command
    and are ignored when specifying completions with -p or --path.

    When erasing completions, it is possible to either erase all
    completions for a specific command by specifying complete -c COMMAND
    -e, or by specifying a specific completion option to delete by
    specifying either a long, short or old style option.

Example
    The short style option -o for the gcc command requires that a file
    follows it. This can be done using writing:

    complete -c gcc -s o -r

    The short style option -d for the grep command requires that one of
    the strings 'read', 'skip' or 'recurse' is used. This can be
    specified writing:

    complete -c grep -s d -x -a 'read skip recurse'

    The su command takes any username as an argument. Usernames are given
    as the first colon-separated field in the file /etc/passwd. This can
    be specified as:

    complete -x -c su -d 'Username' -a '(cat /etc/passwd | cut -d : -f 1)'

    The rpm command has several different modes. If the -e or --erase
    flag has been specified, rpm should delete one or more packages, in
    which case several switches related to deleting packages are valid,
    like the nodeps switch.

    This can be written as:

    complete -c rpm -n '__fish_contains_opt -s e erase' -d nodeps 'Don't check dependencies'

    where __fish_contains_opt is a function that checks the command line
    buffer for the presence of a specified set of options.

    To implement an alias, use the -w or --wraps option:

    complete -c hub -w git

    Now hub inherits all of the completions from git. Note this can also
    be specified in a function declaration.