patch 9.1.0770: current command line completion is a bit limited

Problem:  current command completion is a bit limited
Solution: Add the shellcmdline completion type and getmdcomplpat()
          function (Ruslan Russkikh).

closes: #15823

Signed-off-by: Ruslan Russkikh <dvrussk@yandex.ru>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/doc/builtin.txt

@@ -1,4 +1,4 @@
-*builtin.txt*	For Vim version 9.1.  Last change: 2024 Sep 23
+*builtin.txt*	For Vim version 9.1.  Last change: 2024 Oct 08
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -230,6 +230,8 @@ getcharmod()			Number	modifiers for the last typed character
 getcharpos({expr})		List	position of cursor, mark, etc.
 getcharsearch()			Dict	last character search
 getcharstr([{expr}])		String	get one character from the user
+getcmdcomplpat()		String	return the completion pattern of the
+					current command-line completion
 getcmdcompltype()		String	return the type of the current
 					command-line completion
 getcmdline()			String	return the current command-line input
@@ -3973,6 +3975,16 @@ getcharstr([{expr}])					*getcharstr()*
 
 		Return type: |String|
 
+getcmdcomplpat()					*getcmdcomplpat()*
+		Return completion pattern of the current command-line.
+		Only works when the command line is being edited, thus
+		requires use of |c_CTRL-\_e| or |c_CTRL-R_=|.
+		Also see |getcmdtype()|, |setcmdpos()|, |getcmdline()|,
+		|getcmdprompt()|, |getcmdcompltype()| and |setcmdline()|.
+		Returns an empty string when completion is not defined.
+
+		Return type: |String|
+
 
 getcmdcompltype()					*getcmdcompltype()*
 		Return the type of the current command-line completion.
@@ -3980,7 +3992,7 @@ getcmdcompltype()					*getcmdcompltype()*
 		requires use of |c_CTRL-\_e| or |c_CTRL-R_=|.
 		See |:command-completion| for the return string.
 		Also see |getcmdtype()|, |setcmdpos()|, |getcmdline()|,
-		|getcmdprompt()| and |setcmdline()|.
+		|getcmdprompt()|, |getcmdcomplpat()| and |setcmdline()|.
 		Returns an empty string when completion is not defined.
 
 		Return type: |String|

runtime/doc/map.txt

@@ -1,4 +1,4 @@
-*map.txt*       For Vim version 9.1.  Last change: 2024 Oct 07
+*map.txt*       For Vim version 9.1.  Last change: 2024 Oct 08
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -1657,6 +1657,8 @@ completion can be enabled:
 	-complete=runtime	file and directory names in |'runtimepath'|
 	-complete=scriptnames	sourced script names
 	-complete=shellcmd	Shell command
+	-complete=shellcmdline	First is a shell command and subsequent ones
+				are filenames. The same behavior as |:!cmd|
 	-complete=sign		|:sign| suboptions
 	-complete=syntax	syntax file names |'syntax'|
 	-complete=syntime	|:syntime| suboptions

runtime/doc/tags

@@ -7827,6 +7827,7 @@ getcharmod()	builtin.txt	/*getcharmod()*
 getcharpos()	builtin.txt	/*getcharpos()*
 getcharsearch()	builtin.txt	/*getcharsearch()*
 getcharstr()	builtin.txt	/*getcharstr()*
+getcmdcomplpat()	builtin.txt	/*getcmdcomplpat()*
 getcmdcompltype()	builtin.txt	/*getcmdcompltype()*
 getcmdline()	builtin.txt	/*getcmdline()*
 getcmdpos()	builtin.txt	/*getcmdpos()*

runtime/doc/usr_41.txt

@@ -1068,6 +1068,8 @@ Buffers, windows and the argument list:
 	swapname()		get the swap file path of a buffer
 
 Command line:					*command-line-functions*
+	getcmdcomplpat()	get completion pattern of the current command
+				line
 	getcmdcompltype()	get the type of the current command line
 				completion
 	getcmdline()		get the current command line input

runtime/doc/version9.txt

@@ -1,4 +1,4 @@
-*version9.txt*  For Vim version 9.1.  Last change: 2024 Oct 05
+*version9.txt*  For Vim version 9.1.  Last change: 2024 Oct 08
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -41589,6 +41589,8 @@ Changed~
 - allow to complete directories from 'cdpath' for |:cd| and similar commands,
   add the "cd_in_path" completion type for e.g. |:command-complete| and
   |getcompletion()|
+- allow to complete shell commands and files using the new shellcmdline
+  completion type using |:command-complete| and |getcmdcomplpat()|
 - add 'cpoptions' flag "z" |cpo-z|, to disable some (traditional) vi
   behaviour/inconsistency (see |d-special| and |cw|).
 - allow to specify additional attributes in the completion menu (allows to
@@ -41608,6 +41610,7 @@ Functions: ~
 |diff()|		diff two Lists of strings
 |filecopy()|		copy a file {from} to {to}
 |foreach()|		apply function to List items
+|getcmdcomplpat()|	Shell command line completion
 |getcmdprompt()|	get prompt for input()/confirm()
 |getregion()|		get a region of text from a buffer
 |getregionpos()|	get a list of positions for a region