Merge pull request #22743 from bfredl/luaequals

feat(lua): allow `:=expr` as a shorter version of `:lua =expr`

runtime/doc/lua.txt

@@ -233,11 +233,11 @@ command calls. The |lua-stdlib| modules, user modules, and anything else on
 The Lua print() function redirects its output to the Nvim message area, with
 arguments separated by " " (space) instead of "\t" (tab).
 
-                                                                        *:lua*
+                                                                  *:lua=* *:lua*
 :lua {chunk}
     Executes Lua chunk {chunk}. If {chunk} starts with "=" the rest of the
-    chunk is evaluated as an expression and printed. `:lua =expr` is
-    equivalent to `:lua print(vim.inspect(expr))`
+    chunk is evaluated as an expression and printed. `:lua =expr` or `:=expr` is
+    equivalent to `:lua print(vim.inspect(expr))`.
 
     Examples: >vim
         :lua vim.api.nvim_command('echo "Hello, Nvim!"')

runtime/doc/news.txt

@@ -237,6 +237,11 @@ The following changes to existing APIs or features add new behavior.
 • The `win_viewport` UI event now contains information about virtual lines,
   meaning that smooth scrolling can now be implemented more consistenlty.
 
+• The `:= {expr}` syntax can be used to evaluate a lua expression, as
+  a shorter form of `:lua ={expr}`. `:=` and `:[range]=` without argument
+  are unchanged. However `:=#` and similar variants using |ex-flags|
+  are no longer supported.
+
 ==============================================================================
 REMOVED FEATURES                                                 *news-removed*
 

runtime/doc/various.txt

@@ -173,13 +173,12 @@ g8			Print the hex values of the bytes used in the
 			Like ":z" or ":z!", but number the lines.
 
 							*:=*
-:= [flags]		Print the last line number.
-			See |ex-flags| for [flags].
+:=			Without arg: Print the last line number.
+			with args: equivalent to `:lua ={expr}`. see |:lua|
 
-:{range}= [flags]	Prints the last line number in {range}.  For example,
+:{range}=		Prints the last line number in {range}.  For example,
 			this prints the current line number: >
 				:.=
-<			See |ex-flags| for [flags].
 
 :norm[al][!] {commands}					*:norm* *:normal*
 			Execute Normal mode commands {commands}.  This makes

runtime/doc/vim_diff.txt

@@ -460,6 +460,7 @@ Commands:
   |:doautocmd| does not warn about "No matching autocommands".
   |:wincmd| accepts a count.
   `:write!` does not show a prompt if the file was updated externally.
+  |:=| does not accept |ex-flags|. With an arg it is equivalent to |:lua=|
 
 Command-line:
   The meanings of arrow keys do not change depending on 'wildoptions'.