bash_completion: do not use aliased hg if it sources a script (issue6308)

I have an alias that sources a script around hg. Mercurial's bash_completion
script tries to use this as its main hg binary. But sourcing a wrapper breaks
Bash's completion. So this patch disables using the alias as the hg binary if
it starts with "source ".

Alias resolution was introduced in rev 191ab08e7099 for users with
"alias hg='hg --some_opts'".

See https://www.mercurial-scm.org/repo/hg/rev/191ab08e7099

contrib/bash_completion

@@ -1,656 +1,659 b''
 # bash completion for the Mercurial distributed SCM -*- sh -*-
 
 # Docs:
 #
 # If you source this file from your .bashrc, bash should be able to
 # complete a command line that uses hg with all the available commands
 # and options and sometimes even arguments.
 #
 # Mercurial allows you to define additional commands through extensions.
 # Bash should be able to automatically figure out the name of these new
 # commands and their options.  See below for how to define _hg_opt_foo
 # and _hg_cmd_foo functions to fine-tune the completion for option and
 # non-option arguments, respectively.
 #
 #
 # Notes about completion for specific commands:
 #
 # - the completion function for the email command from the patchbomb
 #   extension will try to call _hg_emails to get a list of e-mail
 #   addresses.  It's up to the user to define this function.  For
 #   example, put the addresses of the lists that you usually patchbomb
 #   in ~/.patchbomb-to and the addresses that you usually use to send
 #   the patchbombs in ~/.patchbomb-from and use something like this:
 #
 #      _hg_emails()
 #      {
 #          if [ -r ~/.patchbomb-$1 ]; then
 #              cat ~/.patchbomb-$1
 #          fi
 #      }
 #
 #
 # Writing completion functions for additional commands:
 #
 # If it exists, the function _hg_cmd_foo will be called without
 # arguments to generate the completion candidates for the hg command
 # "foo".  If the command receives some arguments that aren't options
 # even though they start with a "-", you can define a function called
 # _hg_opt_foo to generate the completion candidates.  If _hg_opt_foo
 # doesn't return 0, regular completion for options is attempted.
 #
 # In addition to the regular completion variables provided by bash,
 # the following variables are also set:
 # - $hg - the hg program being used (e.g. /usr/bin/hg)
 # - $cmd - the name of the hg command being completed
 # - $cmd_index - the index of $cmd in $COMP_WORDS
 # - $cur - the current argument being completed
 # - $prev - the argument before $cur
 # - $global_args - "|"-separated list of global options that accept
 #                  an argument (e.g. '--cwd|-R|--repository')
 # - $canonical - 1 if we canonicalized $cmd before calling the function
 #                0 otherwise
 #
 
 shopt -s extglob
 
 _hg_cmd()
 {
     HGPLAIN=1 "$hg" "$@" 2>/dev/null
 }
 
 _hg_commands()
 {
     local commands
     commands="$(HGPLAINEXCEPT=alias _hg_cmd debugcomplete "$cur")" || commands=""
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$commands' -- "$cur"))
 }
 
 _hg_paths()
 {
     local paths="$(_hg_cmd paths -q)"
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$paths' -- "$cur"))
 }
 
 _hg_repos()
 {
     local i
     for i in $(compgen -d -- "$cur"); do
         test ! -d "$i"/.hg || COMPREPLY=(${COMPREPLY[@]:-} "$i")
     done
 }
 
 _hg_debugpathcomplete()
 {
     local files="$(_hg_cmd debugpathcomplete $1 "$cur")"
     local IFS=$'\n'
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$files' -- "$cur"))
 }
 
 _hg_status()
 {
     if [ -z "$HGCOMPLETE_NOSTATUS" ]; then
         local files="$(_hg_cmd status -n$1 "glob:$cur**")"
         local IFS=$'\n'
         COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$files' -- "$cur"))
     fi
 }
 
 _hg_branches()
 {
     local branches="$(_hg_cmd branches -q)"
     local IFS=$'\n'
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$branches' -- "$cur"))
 }
 
 _hg_bookmarks()
 {
     local bookmarks="$(_hg_cmd bookmarks -q)"
     local IFS=$'\n'
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$bookmarks' -- "$cur"))
 }
 
 _hg_labels()
 {
     local labels="$(_hg_cmd debugnamecomplete "$cur")"
     local IFS=$'\n'
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$labels' -- "$cur"))
 }
 
 # this is "kind of" ugly...
 _hg_count_non_option()
 {
     local i count=0
     local filters="$1"
 
     for ((i=1; $i<=$COMP_CWORD; i++)); do
         if [[ "${COMP_WORDS[i]}" != -* ]]; then
             if [[ ${COMP_WORDS[i-1]} == @($filters|$global_args) ]]; then
                 continue
             fi
             count=$(($count + 1))
         fi
     done
 
     echo $(($count - 1))
 }
 
 _hg_fix_wordlist()
 {
     local LASTCHAR=' '
     if [ ${#COMPREPLY[@]} = 1 ]; then
         [ -d "$COMPREPLY" ] && LASTCHAR=/
         COMPREPLY=$(printf %q%s "$COMPREPLY" "$LASTCHAR")
     else
         for ((i=0; i < ${#COMPREPLY[@]}; i++)); do
             [ -d "${COMPREPLY[$i]}" ] && COMPREPLY[$i]=${COMPREPLY[$i]}/
         done
     fi
 }
 
 _hg()
 {
     local cur prev cmd cmd_index opts i aliashg
     # global options that receive an argument
     local global_args='--cwd|-R|--repository|--color|--config|--encoding|--encodingmode|--pager'
     local hg="$1"
     local canonical=0
 
     aliashg=$(alias $hg 2>/dev/null)
     if [[ -n "$aliashg" ]]; then
       aliashg=${aliashg#"alias $hg='"}
       aliashg=${aliashg%"'"}
-      hg=$aliashg
+      # `source`d aliases break completion, so ignore them
+      if [[ "${aliashg:0:7}" != "source " ]]; then
+        hg=$aliashg
+      fi
     fi
 
     COMPREPLY=()
     cur="$2"
     prev="$3"
 
     # searching for the command
     # (first non-option argument that doesn't follow a global option that
     #  receives an argument)
     for ((i=1; $i<=$COMP_CWORD; i++)); do
         if [[ ${COMP_WORDS[i]} != -* ]]; then
             if [[ ${COMP_WORDS[i-1]} != @($global_args) ]]; then
                 cmd="${COMP_WORDS[i]}"
                 cmd_index=$i
                 break
             fi
         fi
     done
 
     if [[ "$cur" == -* ]]; then
         if [ "$(type -t "_hg_opt_$cmd")" = function ] && "_hg_opt_$cmd"; then
             _hg_fix_wordlist
             return
         fi
 
         opts=$(HGPLAINEXCEPT=alias _hg_cmd debugcomplete --options "$cmd")
 
         COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$opts' -- "$cur"))
         _hg_fix_wordlist
         return
     fi
 
     # global options
     case "$prev" in
         -R|--repository)
             _hg_paths
             _hg_repos
             _hg_fix_wordlist
             return
         ;;
         --cwd)
             # Stick with default bash completion
             _hg_fix_wordlist
             return
         ;;
         --color)
             local choices='true false yes no always auto never debug'
             COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$choices' -- "$cur"))
             _hg_fix_wordlist
             return
         ;;
         --pager)
             local choices='true false yes no always auto never'
             COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$choices' -- "$cur"))
             _hg_fix_wordlist
             return
         ;;
     esac
 
     if [ -z "$cmd" ] || [ $COMP_CWORD -eq $i ]; then
         _hg_commands
         _hg_fix_wordlist
         return
     fi
 
     # try to generate completion candidates for whatever command the user typed
     local help
     if _hg_command_specific; then
         _hg_fix_wordlist
         return
     fi
 
     # canonicalize the command name and try again
     help=$(_hg_cmd help "$cmd")
     if [ $? -ne 0 ]; then
         # Probably either the command doesn't exist or it's ambiguous
         return
     fi
     cmd=${help#hg }
     cmd=${cmd%%[$' \n']*}
     canonical=1
     _hg_command_specific
     _hg_fix_wordlist
 }
 
 _hg_command_specific()
 {
     if [ "$(type -t "_hg_cmd_$cmd")" = function ]; then
         "_hg_cmd_$cmd"
         return 0
     fi
 
     if [ "$cmd" != status ]; then
         case "$prev" in
             -r|--rev)
                 if [[ $canonical = 1 || status != "$cmd"* ]]; then
                     _hg_labels
                     return 0
                 fi
                 return 1
             ;;
             -B|--bookmark)
                 if [[ $canonical = 1 || status != "$cmd"* ]]; then
                     _hg_bookmarks
                     return 0
                 fi
                 return 1
             ;;
             -b|--branch)
                 if [[ $canonical = 1 || status != "$cmd"* ]]; then
                     _hg_branches
                     return 0
                 fi
                 return 1
             ;;
         esac
     fi
 
     local aliascmd=$(_hg_cmd showconfig alias.$cmd | awk '{print $1}')
     [ -n "$aliascmd" ] && cmd=$aliascmd
 
     case "$cmd" in
         help)
             _hg_commands
         ;;
         export)
             if _hg_ext_mq_patchlist qapplied && [ "${COMPREPLY[*]}" ]; then
                 return 0
             fi
             _hg_labels
         ;;
         manifest|update|up|checkout|co)
             _hg_labels
         ;;
         pull|push|outgoing|incoming)
             _hg_paths
             _hg_repos
         ;;
         paths)
             _hg_paths
         ;;
         add)
             _hg_status "u"
         ;;
         merge)
             _hg_labels
         ;;
         commit|ci|record|amend)
             _hg_status "mar"
         ;;
         remove|rm)
             _hg_debugpathcomplete -n
         ;;
         forget)
             _hg_debugpathcomplete -fa
         ;;
         diff)
             _hg_status "mar"
         ;;
         revert)
             _hg_status "mard"
         ;;
         clone)
             local count=$(_hg_count_non_option)
             if [ $count = 1 ]; then
                 _hg_paths
             fi
             _hg_repos
         ;;
         debugindex|debugindexdot)
             COMPREPLY=(${COMPREPLY[@]:-} $(compgen -f -X "!*.i" -- "$cur"))
         ;;
         debugdata)
             COMPREPLY=(${COMPREPLY[@]:-} $(compgen -f -X "!*.d" -- "$cur"))
         ;;
         *)
             return 1
         ;;
     esac
 
     return 0
 }
 
 complete -o bashdefault -o default -o nospace -F _hg hg \
     || complete -o default -o nospace -F _hg hg
 
 
 # Completion for commands provided by extensions
 
 # bookmarks
 _hg_cmd_bookmarks()
 {
     _hg_bookmarks
     return
 }
 
 # mq
 _hg_ext_mq_patchlist()
 {
     local patches
     patches=$(_hg_cmd $1)
     if [ $? -eq 0 ] && [ "$patches" ]; then
         COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$patches' -- "$cur"))
         return 0
     fi
     return 1
 }
 
 _hg_ext_mq_queues()
 {
     local root=$(_hg_cmd root)
     local n
     for n in $(cd "$root"/.hg && compgen -d -- "$cur"); do
         # I think we're usually not interested in the regular "patches" queue
         # so just filter it.
         if [ "$n" != patches ] && [ -e "$root/.hg/$n/series" ]; then
             COMPREPLY=(${COMPREPLY[@]:-} "$n")
         fi
     done
 }
 
 _hg_cmd_qpop()
 {
     if [[ "$prev" = @(-n|--name) ]]; then
         _hg_ext_mq_queues
         return
     fi
     _hg_ext_mq_patchlist qapplied
 }
 
 _hg_cmd_qpush()
 {
     if [[ "$prev" = @(-n|--name) ]]; then
         _hg_ext_mq_queues
         return
     fi
     _hg_ext_mq_patchlist qunapplied
 }
 
 _hg_cmd_qgoto()
 {
     if [[ "$prev" = @(-n|--name) ]]; then
         _hg_ext_mq_queues
         return
     fi
     _hg_ext_mq_patchlist qseries
 }
 
 _hg_cmd_qdelete()
 {
     local qcmd=qunapplied
     if [[ "$prev" = @(-r|--rev) ]]; then
         qcmd=qapplied
     fi
     _hg_ext_mq_patchlist $qcmd
 }
 
 _hg_cmd_qfinish()
 {
     if [[ "$prev" = @(-a|--applied) ]]; then
         return
     fi
     _hg_ext_mq_patchlist qapplied
 }
 
 _hg_cmd_qsave()
 {
     if [[ "$prev" = @(-n|--name) ]]; then
         _hg_ext_mq_queues
         return
     fi
 }
 
 _hg_cmd_rebase() {
    if [[ "$prev" = @(-s|--source|-d|--dest|-b|--base|-r|--rev) ]]; then
        _hg_labels
        return
    fi
 }
 
 _hg_cmd_strip()
 {
     if [[ "$prev" = @(-B|--bookmark) ]]; then
         _hg_bookmarks
         return
     fi
     _hg_labels
 }
 
 _hg_cmd_qcommit()
 {
     local root=$(_hg_cmd root)
     # this is run in a sub-shell, so we can't use _hg_status
     local files=$(cd "$root/.hg/patches" && _hg_cmd status -nmar)
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$files' -- "$cur"))
 }
 
 _hg_cmd_qfold()
 {
     _hg_ext_mq_patchlist qunapplied
 }
 
 _hg_cmd_qrename()
 {
     _hg_ext_mq_patchlist qseries
 }
 
 _hg_cmd_qheader()
 {
     _hg_ext_mq_patchlist qseries
 }
 
 _hg_cmd_qclone()
 {
     local count=$(_hg_count_non_option)
     if [ $count = 1 ]; then
         _hg_paths
     fi
     _hg_repos
 }
 
 _hg_ext_mq_guards()
 {
     _hg_cmd qselect --series | sed -e 's/^.//'
 }
 
 _hg_cmd_qselect()
 {
     local guards=$(_hg_ext_mq_guards)
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$guards' -- "$cur"))
 }
 
 _hg_cmd_qguard()
 {
     local prefix=''
 
     if [[ "$cur" == +* ]]; then
         prefix=+
     elif [[ "$cur" == -* ]]; then
         prefix=-
     fi
     local ncur=${cur#[-+]}
 
     if ! [ "$prefix" ]; then
         _hg_ext_mq_patchlist qseries
         return
     fi
 
     local guards=$(_hg_ext_mq_guards)
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -P $prefix -W '$guards' -- "$ncur"))
 }
 
 _hg_opt_qguard()
 {
     local i
     for ((i=cmd_index+1; i<=COMP_CWORD; i++)); do
         if [[ ${COMP_WORDS[i]} != -* ]]; then
             if [[ ${COMP_WORDS[i-1]} != @($global_args) ]]; then
                 _hg_cmd_qguard
                 return 0
             fi
         elif [ "${COMP_WORDS[i]}" = -- ]; then
             _hg_cmd_qguard
             return 0
         fi
     done
     return 1
 }
 
 _hg_cmd_qqueue()
 {
     local q
     local queues
     local opts="--list --create --rename --delete --purge"
 
     queues=$( _hg_cmd qqueue --quiet )
 
     COMPREPLY=( $( compgen -W "${opts} ${queues}" "${cur}" ) )
 }
 
 
 # hbisect
 _hg_cmd_bisect()
 {
     local i subcmd
 
     # find the sub-command
     for ((i=cmd_index+1; i<=COMP_CWORD; i++)); do
         if [[ ${COMP_WORDS[i]} != -* ]]; then
             if [[ ${COMP_WORDS[i-1]} != @($global_args) ]]; then
                 subcmd="${COMP_WORDS[i]}"
                 break
             fi
         fi
     done
 
     if [ -z "$subcmd" ] || [ $COMP_CWORD -eq $i ] || [ "$subcmd" = help ]; then
         COMPREPLY=(${COMPREPLY[@]:-}
                    $(compgen -W 'bad good help init next reset' -- "$cur"))
         return
     fi
 
     case "$subcmd" in
         good|bad)
             _hg_labels
             ;;
     esac
 
     return
 }
 
 
 # patchbomb
 _hg_cmd_email()
 {
     case "$prev" in
         -c|--cc|-t|--to|-f|--from|--bcc)
             # we need an e-mail address. let the user provide a function
             # to get them
             if [ "$(type -t _hg_emails)" = function ]; then
                 local arg=to
                 if [[ "$prev" == @(-f|--from) ]]; then
                     arg=from
                 fi
                 local addresses=$(_hg_emails $arg)
                 COMPREPLY=(${COMPREPLY[@]:-}
                            $(compgen -W '$addresses' -- "$cur"))
             fi
             return
             ;;
         -m|--mbox)
             # fallback to standard filename completion
             return
             ;;
         -s|--subject)
             # free form string
             return
             ;;
     esac
 
     _hg_labels
     return
 }
 
 
 # gpg
 _hg_cmd_sign()
 {
     _hg_labels
 }
 
 
 # transplant
 _hg_cmd_transplant()
 {
     case "$prev" in
         -s|--source)
             _hg_paths
             _hg_repos
             return
             ;;
         --filter)
             # standard filename completion
             return
             ;;
     esac
 
     # all other transplant options values and command parameters are revisions
     _hg_labels
     return
 }
 
 # shelve
 _hg_shelves()
 {
     local shelves="$(_hg_cmd shelve -ql)"
     local IFS=$'\n'
     COMPREPLY=(${COMPREPLY[@]:-} $(compgen -W '$shelves' -- "$cur"))
 }
 
 _hg_cmd_shelve()
 {
     if [[ "$prev" = @(-d|--delete|-l|--list|-p|--patch|--stat) ]]; then
         _hg_shelves
     else
         _hg_status "mard"
     fi
 }
 
 _hg_cmd_unshelve()
 {
     _hg_shelves
 }