read: add --list as synonym for --array

Work on #5846.

sphinx_doc_src/cmds/read.rst

@@ -43,7 +43,7 @@ The following options are available:
 
 - ``-x`` or ``--export`` exports the variables to child processes.
 
-- ``-a`` or ``--array`` stores the result as a list in a single variable.
+- ``-a`` or ``--list`` stores the result as a list in a single variable. This option is also available as ``--array`` for backwards compatibility.
 
 - ``-z`` or ``--null`` marks the end of the line with the NUL character, instead of newline. This also
   disables interactive mode.

src/builtin_read.cpp

@@ -62,6 +62,7 @@ static const struct woption long_options[] = {{L"array", no_argument, NULL, 'a'}
                                               {L"global", no_argument, NULL, 'g'},
                                               {L"help", no_argument, NULL, 'h'},
                                               {L"line", no_argument, NULL, 'L'},
+                                              {L"list", no_argument, NULL, 'a'},
                                               {L"local", no_argument, NULL, 'l'},
                                               {L"nchars", required_argument, NULL, 'n'},
                                               {L"null", no_argument, NULL, 'z'},

tests/read.in

@@ -10,8 +10,8 @@ read
 
 logmsg Read with -a and anything other than exactly on var name is an error
 read -a
-read -a v1 v2
-read -a v1
+read --array v1 v2
+read --list v1
 
 logmsg Verify correct behavior of subcommands and splitting of input.
 begin