chore: Do not generate completion for help help

`foo help help` is not really that useful. Generating `help help`
completion is causing bug in
<#4115 (comment)>.

clap_complete/src/shells/fish.rs

@@ -68,12 +68,18 @@ fn gen_fish_inner(
         }
     } else {
         let mut out = String::from("__fish_seen_subcommand_from");
+        let mut is_help_subcommand = false;
         for &command in parent_commands {
+            if command == "help" {
+                is_help_subcommand = true;
+            }
             out.push(' ');
             out.push_str(command);
         }
         let subcommands: Vec<&str> = cmd
             .get_subcommands()
+            // "foo help help" is not really that useful and causing a bug
+            .filter(|sub| !(sub.get_name() == "help" && is_help_subcommand))
             .flat_map(Command::get_name_and_visible_aliases)
             .collect();
         if !subcommands.is_empty() {

clap_complete/tests/snapshots/basic.fish

@@ -6,5 +6,5 @@ complete -c my-app -n "__fish_use_subcommand" -f -a "help" -d 'Print this messag
 complete -c my-app -n "__fish_seen_subcommand_from test" -s d
 complete -c my-app -n "__fish_seen_subcommand_from test" -s c
 complete -c my-app -n "__fish_seen_subcommand_from test" -s h -l help -d 'Print help'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test help" -f -a "test" -d 'Subcommand with a second line'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test" -f -a "test" -d 'Subcommand with a second line'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'

clap_complete/tests/snapshots/custom_bin_name.fish

@@ -6,5 +6,5 @@ complete -c bin-name -n "__fish_use_subcommand" -f -a "help" -d 'Print this mess
 complete -c bin-name -n "__fish_seen_subcommand_from test" -s d
 complete -c bin-name -n "__fish_seen_subcommand_from test" -s c
 complete -c bin-name -n "__fish_seen_subcommand_from test" -s h -l help -d 'Print help'
-complete -c bin-name -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test help" -f -a "test" -d 'Subcommand with a second line'
-complete -c bin-name -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
+complete -c bin-name -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test" -f -a "test" -d 'Subcommand with a second line'
+complete -c bin-name -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'

clap_complete/tests/snapshots/feature_sample.fish

@@ -6,5 +6,5 @@ complete -c my-app -n "__fish_use_subcommand" -f -a "help" -d 'Print this messag
 complete -c my-app -n "__fish_seen_subcommand_from test" -l case -d 'the case to test' -r
 complete -c my-app -n "__fish_seen_subcommand_from test" -s h -l help -d 'Print help'
 complete -c my-app -n "__fish_seen_subcommand_from test" -s V -l version -d 'Print version'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test help" -f -a "test" -d 'tests things'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test" -f -a "test" -d 'tests things'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from test" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'

clap_complete/tests/snapshots/home/static/exhaustive/fish/fish/completions/exhaustive.fish

@@ -57,14 +57,14 @@ complete -c exhaustive -n "__fish_seen_subcommand_from quote cmd-expansions" -s
 complete -c exhaustive -n "__fish_seen_subcommand_from quote escape-help" -l global -d 'everywhere'
 complete -c exhaustive -n "__fish_seen_subcommand_from quote escape-help" -s h -l help -d 'Print help'
 complete -c exhaustive -n "__fish_seen_subcommand_from quote escape-help" -s V -l version -d 'Print version'
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "cmd-single-quotes" -d 'Can be \'always\', \'auto\', or \'never\''
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "cmd-double-quotes" -d 'Can be "always", "auto", or "never"'
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "cmd-backticks" -d 'For more information see `echo test`'
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "cmd-backslash" -d 'Avoid \'\\n\''
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "cmd-brackets" -d 'List packages [filter]'
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "cmd-expansions" -d 'Execute the shell command with $SHELL'
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "escape-help" -d '\\tab	"\' New Line'
-complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-single-quotes" -d 'Can be \'always\', \'auto\', or \'never\''
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-double-quotes" -d 'Can be "always", "auto", or "never"'
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-backticks" -d 'For more information see `echo test`'
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-backslash" -d 'Avoid \'\\n\''
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-brackets" -d 'List packages [filter]'
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-expansions" -d 'Execute the shell command with $SHELL'
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "escape-help" -d '\\tab	"\' New Line'
+complete -c exhaustive -n "__fish_seen_subcommand_from quote help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
 complete -c exhaustive -n "__fish_seen_subcommand_from value" -l delim -r
 complete -c exhaustive -n "__fish_seen_subcommand_from value" -l tuple -r
 complete -c exhaustive -n "__fish_seen_subcommand_from value" -l require-eq -r
@@ -83,9 +83,9 @@ complete -c exhaustive -n "__fish_seen_subcommand_from pacman one" -s V -l versi
 complete -c exhaustive -n "__fish_seen_subcommand_from pacman two" -l global -d 'everywhere'
 complete -c exhaustive -n "__fish_seen_subcommand_from pacman two" -s h -l help -d 'Print help'
 complete -c exhaustive -n "__fish_seen_subcommand_from pacman two" -s V -l version -d 'Print version'
-complete -c exhaustive -n "__fish_seen_subcommand_from pacman help; and not __fish_seen_subcommand_from one two help" -f -a "one"
-complete -c exhaustive -n "__fish_seen_subcommand_from pacman help; and not __fish_seen_subcommand_from one two help" -f -a "two"
-complete -c exhaustive -n "__fish_seen_subcommand_from pacman help; and not __fish_seen_subcommand_from one two help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
+complete -c exhaustive -n "__fish_seen_subcommand_from pacman help; and not __fish_seen_subcommand_from one two" -f -a "one"
+complete -c exhaustive -n "__fish_seen_subcommand_from pacman help; and not __fish_seen_subcommand_from one two" -f -a "two"
+complete -c exhaustive -n "__fish_seen_subcommand_from pacman help; and not __fish_seen_subcommand_from one two" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
 complete -c exhaustive -n "__fish_seen_subcommand_from last" -l global -d 'everywhere'
 complete -c exhaustive -n "__fish_seen_subcommand_from last" -s h -l help -d 'Print help'
 complete -c exhaustive -n "__fish_seen_subcommand_from last" -s V -l version -d 'Print version'
@@ -115,15 +115,15 @@ complete -c exhaustive -n "__fish_seen_subcommand_from complete" -l register -d
 complete -c exhaustive -n "__fish_seen_subcommand_from complete" -l global -d 'everywhere'
 complete -c exhaustive -n "__fish_seen_subcommand_from complete" -s h -l help -d 'Print help (see more with \'--help\')'
 complete -c exhaustive -n "__fish_seen_subcommand_from complete" -s V -l version -d 'Print version'
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "action"
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "quote"
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "value"
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "pacman"
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "last"
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "alias"
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "hint"
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "complete" -d 'Register shell completions for this program'
-complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "action"
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "quote"
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "value"
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "pacman"
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "last"
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "alias"
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "hint"
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "complete" -d 'Register shell completions for this program'
+complete -c exhaustive -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from action quote value pacman last alias hint complete" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
 complete -c exhaustive -n "__fish_seen_subcommand_from help quote; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-single-quotes" -d 'Can be \'always\', \'auto\', or \'never\''
 complete -c exhaustive -n "__fish_seen_subcommand_from help quote; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-double-quotes" -d 'Can be "always", "auto", or "never"'
 complete -c exhaustive -n "__fish_seen_subcommand_from help quote; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions escape-help" -f -a "cmd-backticks" -d 'For more information see `echo test`'

clap_complete/tests/snapshots/quoting.fish

@@ -19,10 +19,10 @@ complete -c my-app -n "__fish_seen_subcommand_from cmd-backticks" -s h -l help -
 complete -c my-app -n "__fish_seen_subcommand_from cmd-backslash" -s h -l help -d 'Print help'
 complete -c my-app -n "__fish_seen_subcommand_from cmd-brackets" -s h -l help -d 'Print help'
 complete -c my-app -n "__fish_seen_subcommand_from cmd-expansions" -s h -l help -d 'Print help'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions help" -f -a "cmd-single-quotes" -d 'Can be \'always\', \'auto\', or \'never\''
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions help" -f -a "cmd-double-quotes" -d 'Can be "always", "auto", or "never"'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions help" -f -a "cmd-backticks" -d 'For more information see `echo test`'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions help" -f -a "cmd-backslash" -d 'Avoid \'\\n\''
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions help" -f -a "cmd-brackets" -d 'List packages [filter]'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions help" -f -a "cmd-expansions" -d 'Execute the shell command with $SHELL'
-complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions help" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions" -f -a "cmd-single-quotes" -d 'Can be \'always\', \'auto\', or \'never\''
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions" -f -a "cmd-double-quotes" -d 'Can be "always", "auto", or "never"'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions" -f -a "cmd-backticks" -d 'For more information see `echo test`'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions" -f -a "cmd-backslash" -d 'Avoid \'\\n\''
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions" -f -a "cmd-brackets" -d 'List packages [filter]'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions" -f -a "cmd-expansions" -d 'Execute the shell command with $SHELL'
+complete -c my-app -n "__fish_seen_subcommand_from help; and not __fish_seen_subcommand_from cmd-single-quotes cmd-double-quotes cmd-backticks cmd-backslash cmd-brackets cmd-expansions" -f -a "help" -d 'Print this message or the help of the given subcommand(s)'