fix(complete): make git diff git <TAB> Bash-complete for git diff

Early in the Bash-completion script, we build up a string that
identifies the command or subcommand. When we see the top-level
command's name (e.g. `git`) we set the command so far to that
value. We do that regardless of where in the argument list it
appears. For example, if the argument list is `git diff git`, we set
the current command to `git` when run into it the second time. We
therefore suggest arguments to the top-level command afterwards, which
is not correct.

This patch fixes that by also considering the string that identifies
the command so far, so we only set the overall command to `git` if the
command so far is the empty string.

This is actually just a step on the way to getting completion to work
for aliases of subcommands.

Closes clap-rs#4273

clap_complete/src/shells/bash.rs

@@ -31,8 +31,8 @@ impl Generator for Bash {
 
     for i in ${{COMP_WORDS[@]}}
     do
-        case \"${{i}}\" in
-            \"$1\")
+        case \"${{cmd}},${{i}}\" in
+            \",$1\")
                 cmd=\"{cmd}\"
                 ;;{subcmds}
             *)
@@ -86,7 +86,7 @@ fn all_subcommands(cmd: &Command) -> String {
 
     subcmds.extend(scs.iter().map(|sc| {
         format!(
-            "{name})
+            "*,{name})
                 cmd+=\"__{fn_name}\"
                 ;;",
             name = sc,

clap_complete/tests/snapshots/aliases.bash

@@ -8,8 +8,8 @@ _my-app() {
 
     for i in ${COMP_WORDS[@]}
     do
-        case "${i}" in
-            "$1")
+        case "${cmd},${i}" in
+            ",$1")
                 cmd="my__app"
                 ;;
             *)

clap_complete/tests/snapshots/basic.bash

@@ -8,14 +8,14 @@ _my-app() {
 
     for i in ${COMP_WORDS[@]}
     do
-        case "${i}" in
-            "$1")
+        case "${cmd},${i}" in
+            ",$1")
                 cmd="my__app"
                 ;;
-            help)
+            *,help)
                 cmd+="__help"
                 ;;
-            test)
+            *,test)
                 cmd+="__test"
                 ;;
             *)

clap_complete/tests/snapshots/feature_sample.bash

@@ -8,14 +8,14 @@ _my-app() {
 
     for i in ${COMP_WORDS[@]}
     do
-        case "${i}" in
-            "$1")
+        case "${cmd},${i}" in
+            ",$1")
                 cmd="my__app"
                 ;;
-            help)
+            *,help)
                 cmd+="__help"
                 ;;
-            test)
+            *,test)
                 cmd+="__test"
                 ;;
             *)

clap_complete/tests/snapshots/quoting.bash

@@ -8,29 +8,29 @@ _my-app() {
 
     for i in ${COMP_WORDS[@]}
     do
-        case "${i}" in
-            "$1")
+        case "${cmd},${i}" in
+            ",$1")
                 cmd="my__app"
                 ;;
-            cmd-backslash)
+            *,cmd-backslash)
                 cmd+="__cmd__backslash"
                 ;;
-            cmd-backticks)
+            *,cmd-backticks)
                 cmd+="__cmd__backticks"
                 ;;
-            cmd-brackets)
+            *,cmd-brackets)
                 cmd+="__cmd__brackets"
                 ;;
-            cmd-double-quotes)
+            *,cmd-double-quotes)
                 cmd+="__cmd__double__quotes"
                 ;;
-            cmd-expansions)
+            *,cmd-expansions)
                 cmd+="__cmd__expansions"
                 ;;
-            cmd-single-quotes)
+            *,cmd-single-quotes)
                 cmd+="__cmd__single__quotes"
                 ;;
-            help)
+            *,help)
                 cmd+="__help"
                 ;;
             *)

clap_complete/tests/snapshots/special_commands.bash

@@ -8,23 +8,23 @@ _my-app() {
 
     for i in ${COMP_WORDS[@]}
     do
-        case "${i}" in
-            "$1")
+        case "${cmd},${i}" in
+            ",$1")
                 cmd="my__app"
                 ;;
-            help)
+            *,help)
                 cmd+="__help"
                 ;;
-            some-cmd-with-hyphens)
+            *,some-cmd-with-hyphens)
                 cmd+="__some__cmd__with__hyphens"
                 ;;
-            some-hidden-cmd)
+            *,some-hidden-cmd)
                 cmd+="__some__hidden__cmd"
                 ;;
-            some_cmd)
+            *,some_cmd)
                 cmd+="__some_cmd"
                 ;;
-            test)
+            *,test)
                 cmd+="__test"
                 ;;
             *)

clap_complete/tests/snapshots/sub_subcommands.bash

@@ -8,20 +8,20 @@ _my-app() {
 
     for i in ${COMP_WORDS[@]}
     do
-        case "${i}" in
-            "$1")
+        case "${cmd},${i}" in
+            ",$1")
                 cmd="my__app"
                 ;;
-            help)
+            *,help)
                 cmd+="__help"
                 ;;
-            some_cmd)
+            *,some_cmd)
                 cmd+="__some_cmd"
                 ;;
-            sub_cmd)
+            *,sub_cmd)
                 cmd+="__sub_cmd"
                 ;;
-            test)
+            *,test)
                 cmd+="__test"
                 ;;
             *)

clap_complete/tests/snapshots/value_hint.bash

@@ -8,8 +8,8 @@ _my-app() {
 
     for i in ${COMP_WORDS[@]}
     do
-        case "${i}" in
-            "$1")
+        case "${cmd},${i}" in
+            ",$1")
                 cmd="my__app"
                 ;;
             *)