patch 8.1.1954: more functions can be used as a method

Problem:    More functions can be used as a method.
Solution:   Allow more functions to be used as a method.

runtime/doc/eval.txt

@@ -1228,7 +1228,7 @@ next method: >
 	mylist->filter(filterexpr)->map(mapexpr)->sort()->join()
 <
 Example of using a lambda: >
-	GetPercentage->{x -> x * 100}()->printf('%d%%')
+	GetPercentage()->{x -> x * 100}()->printf('%d%%')
 <
 When using -> the |expr7| operators will be applied first, thus: >
 	-1.234->string()
@@ -6206,6 +6206,9 @@ js_decode({string})					*js_decode()*
 		- Empty items in an array (between two commas) are allowed and
 		  result in v:none items.
 
+		Can also be used as a |method|: >
+			ReadObject()->js_decode()
+
 js_encode({expr})					*js_encode()*
 		This is similar to |json_encode()| with these differences:
 		- Object key names are not in quotes.
@@ -6220,6 +6223,8 @@ js_encode({expr})					*js_encode()*
 		This encoding is valid for JavaScript. It is more efficient
 		than JSON, especially when using an array with optional items.
 
+		Can also be used as a |method|: >
+			GetObject()->js_encode()
 
 json_decode({string})					*json_decode()*
 		This parses a JSON formatted string and returns the equivalent
@@ -6254,6 +6259,8 @@ json_decode({string})					*json_decode()*
 		accepted by json_decode() as the result must be a valid Vim
 		type, e.g. this fails: {"a":"b", "a":"c"}
 
+		Can also be used as a |method|: >
+			ReadObject()->json_decode()
 
 json_encode({expr})					*json_encode()*
 		Encode {expr} as JSON and return this as a string.
@@ -6280,6 +6287,9 @@ json_encode({expr})					*json_encode()*
 		missing in the JSON standard, but several implementations do
 		allow it.  If not then you will get an error.
 
+		Can also be used as a |method|: >
+			GetObject()->json_encode()
+
 keys({dict})						*keys()*
 		Return a |List| with all the keys of {dict}.  The |List| is in
 		arbitrary order.  Also see |items()| and |values()|.
@@ -6346,6 +6356,10 @@ libcall({libname}, {funcname}, {argument})
 		feature is present}
 		Examples: >
 			:echo libcall("libc.so", "getenv", "HOME")
+
+<		Can also be used as a |method|, where the base is passed as
+		the argument to the called function: >
+			GetValue()->libcall("libc.so", "getenv")
 <
 							*libcallnr()*
 libcallnr({libname}, {funcname}, {argument})
@@ -6357,6 +6371,10 @@ libcallnr({libname}, {funcname}, {argument})
 			:echo libcallnr("/usr/lib/libc.so", "getpid", "")
 			:call libcallnr("libc.so", "printf", "Hello World!\n")
 			:call libcallnr("libc.so", "sleep", 10)
+<
+		Can also be used as a |method|, where the base is passed as
+		the argument to the called function: >
+			GetValue()->libcallnr("libc.so", "printf")
 <
 							*line()*
 line({expr})	The result is a Number, which is the line number of the file
@@ -6385,6 +6403,9 @@ line({expr})	The result is a Number, which is the line number of the file
 		To jump to the last known position when opening a file see
 		|last-position-jump|.
 
+		Can also be used as a |method|: >
+			GetValue()->line()
+
 line2byte({lnum})					*line2byte()*
 		Return the byte count from the start of the buffer for line
 		{lnum}.  This includes the end-of-line character, depending on
@@ -6399,6 +6420,9 @@ line2byte({lnum})					*line2byte()*
 		disabled at compile time, -1 is returned.
 		Also see |byte2line()|, |go| and |:goto|.
 
+		Can also be used as a |method|: >
+			GetLnum()->line2byte()
+
 lispindent({lnum})					*lispindent()*
 		Get the amount of indent for line {lnum} according the lisp
 		indenting rules, as with 'lisp'.
@@ -6407,6 +6431,9 @@ lispindent({lnum})					*lispindent()*
 		When {lnum} is invalid or Vim was not compiled the
 		|+lispindent| feature, -1 is returned.
 
+		Can also be used as a |method|: >
+			GetLnum()->lispindent()
+
 list2str({list} [, {utf8}])				*list2str()*
 		Convert each number in {list} to a character string can
 		concatenate them all.  Examples: >
@@ -6421,6 +6448,9 @@ list2str({list} [, {utf8}])				*list2str()*
 		With utf-8 composing characters work as expected: >
 			list2str([97, 769])	returns "á"
 <
+		Can also be used as a |method|: >
+			GetList()->list2str()
+
 listener_add({callback} [, {buf}])			*listener_add()*
 		Add a callback function that will be invoked when changes have
 		been made to buffer {buf}.
@@ -6490,6 +6520,10 @@ listener_add({callback} [, {buf}])			*listener_add()*
 		The {callback} is also not invoked when the buffer is
 		unloaded, use the |BufUnload| autocmd event for that.
 
+		Can also be used as a |method|, where the base is passed as
+		the second argument, the buffer: >
+			GetBuffer()->listener_add(callback)
+
 listener_flush([{buf}])					*listener_flush()*
 		Invoke listener callbacks for buffer {buf}.  If there are no
 		pending changes then no callbacks are invoked.
@@ -6498,11 +6532,17 @@ listener_flush([{buf}])					*listener_flush()*
 		values, see |bufname()|.  When {buf} is omitted the current
 		buffer is used.
 
+		Can also be used as a |method|: >
+			GetBuffer()->listener_flush()
+
 listener_remove({id})					*listener_remove()*
 		Remove a listener previously added with listener_add().
 		Returns zero when {id} could not be found, one when {id} was
 		removed.
 
+		Can also be used as a |method|: >
+			GetListenerId()->listener_remove()
+
 localtime()						*localtime()*
 		Return the current time, measured as seconds since 1st Jan
 		1970.  See also |strftime()| and |getftime()|.
@@ -6550,7 +6590,11 @@ luaeval({expr} [, {expr}])					*luaeval()*
 		as-is.
 		Other objects are returned as zero without any errors.
 		See |lua-luaeval| for more details.
-		{only available when compiled with the |+lua| feature}
+
+		Can also be used as a |method|: >
+			GetExpr()->luaeval()
+
+<		{only available when compiled with the |+lua| feature}
 
 map({expr1}, {expr2})					*map()*
 		{expr1} must be a |List| or a |Dictionary|.

src/evalfunc.c

@@ -635,29 +635,29 @@ static funcentry_T global_functions[] =
     {"job_stop",	1, 2, FEARG_1,	  f_job_stop},
 #endif
     {"join",		1, 2, FEARG_1,	  f_join},
-    {"js_decode",	1, 1, 0,	  f_js_decode},
-    {"js_encode",	1, 1, 0,	  f_js_encode},
-    {"json_decode",	1, 1, 0,	  f_json_decode},
-    {"json_encode",	1, 1, 0,	  f_json_encode},
+    {"js_decode",	1, 1, FEARG_1,	  f_js_decode},
+    {"js_encode",	1, 1, FEARG_1,	  f_js_encode},
+    {"json_decode",	1, 1, FEARG_1,	  f_json_decode},
+    {"json_encode",	1, 1, FEARG_1,	  f_json_encode},
     {"keys",		1, 1, FEARG_1,	  f_keys},
     {"last_buffer_nr",	0, 0, 0,	  f_last_buffer_nr}, // obsolete
     {"len",		1, 1, FEARG_1,	  f_len},
-    {"libcall",		3, 3, 0,	  f_libcall},
-    {"libcallnr",	3, 3, 0,	  f_libcallnr},
-    {"line",		1, 1, 0,	  f_line},
-    {"line2byte",	1, 1, 0,	  f_line2byte},
-    {"lispindent",	1, 1, 0,	  f_lispindent},
-    {"list2str",	1, 2, 0,	  f_list2str},
-    {"listener_add",	1, 2, 0,	  f_listener_add},
-    {"listener_flush",	0, 1, 0,	  f_listener_flush},
-    {"listener_remove",	1, 1, 0,	  f_listener_remove},
+    {"libcall",		3, 3, FEARG_3,	  f_libcall},
+    {"libcallnr",	3, 3, FEARG_3,	  f_libcallnr},
+    {"line",		1, 1, FEARG_1,	  f_line},
+    {"line2byte",	1, 1, FEARG_1,	  f_line2byte},
+    {"lispindent",	1, 1, FEARG_1,	  f_lispindent},
+    {"list2str",	1, 2, FEARG_1,	  f_list2str},
+    {"listener_add",	1, 2, FEARG_2,	  f_listener_add},
+    {"listener_flush",	0, 1, FEARG_1,	  f_listener_flush},
+    {"listener_remove",	1, 1, FEARG_1,	  f_listener_remove},
     {"localtime",	0, 0, 0,	  f_localtime},
 #ifdef FEAT_FLOAT
     {"log",		1, 1, FEARG_1,	  f_log},
     {"log10",		1, 1, FEARG_1,	  f_log10},
 #endif
 #ifdef FEAT_LUA
-    {"luaeval",		1, 2, 0,	  f_luaeval},
+    {"luaeval",		1, 2, FEARG_1,	  f_luaeval},
 #endif
     {"map",		2, 2, FEARG_1,	  f_map},
     {"maparg",		1, 4, 0,	  f_maparg},

src/testdir/test_arglist.vim

@@ -88,7 +88,7 @@ func Test_argadd_empty_curbuf()
   argadd Xargadd
   call assert_equal(curbuf, bufnr('%'))
   call assert_equal('', bufname('%'))
-  call assert_equal(1, line('$'))
+  call assert_equal(1, '$'->line())
   rew
   call assert_notequal(curbuf, '%'->bufnr())
   call assert_equal('Xargadd', '%'->bufname())

src/testdir/test_functions.vim

@@ -883,7 +883,7 @@ func Test_byte2line_line2byte()
   call assert_equal([-1, -1, 1, 1, 2, 2, 2, 3, 3, -1],
   \                 map(range(-1, 8), 'v:val->byte2line()'))
   call assert_equal([-1, -1, 1, 3, 6, 8, -1],
-  \                 map(range(-1, 5), 'line2byte(v:val)'))
+  \                 map(range(-1, 5), 'v:val->line2byte()'))
 
   set fileformat=dos
   call assert_equal([-1, -1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, -1],
@@ -1351,17 +1351,17 @@ func Test_libcall_libcallnr()
   endif
 
   if has('win32')
-    call assert_equal($USERPROFILE, libcall(libc, 'getenv', 'USERPROFILE'))
+    call assert_equal($USERPROFILE, 'USERPROFILE'->libcall(libc, 'getenv'))
   else
-    call assert_equal($HOME, libcall(libc, 'getenv', 'HOME'))
+    call assert_equal($HOME, 'HOME'->libcall(libc, 'getenv'))
   endif
 
   " If function returns NULL, libcall() should return an empty string.
   call assert_equal('', libcall(libc, 'getenv', 'X_ENV_DOES_NOT_EXIT'))
 
   " Test libcallnr() with string and integer argument.
-  call assert_equal(4, libcallnr(libc, 'strlen', 'abcd'))
-  call assert_equal(char2nr('A'), libcallnr(libc, 'toupper', char2nr('a')))
+  call assert_equal(4, 'abcd'->libcallnr(libc, 'strlen'))
+  call assert_equal(char2nr('A'), char2nr('a')->libcallnr(libc, 'toupper'))
 
   call assert_fails("call libcall(libc, 'Xdoesnotexist_', '')", 'E364:')
   call assert_fails("call libcallnr(libc, 'Xdoesnotexist_', '')", 'E364:')

src/testdir/test_json.vim

@@ -70,7 +70,7 @@ let s:varvals = [v:true, v:false, v:null, v:null]
 func Test_json_encode()
   call assert_equal(s:json1, json_encode(s:var1))
   call assert_equal(s:json2, json_encode(s:var2))
-  call assert_equal(s:json3, json_encode(s:var3))
+  call assert_equal(s:json3, s:var3->json_encode())
   call assert_equal(s:json4, json_encode(s:var4))
   call assert_equal(s:json5, json_encode(s:var5))
 
@@ -110,7 +110,7 @@ endfunc
 func Test_json_decode()
   call assert_equal(s:var1, json_decode(s:json1))
   call assert_equal(s:var2, json_decode(s:json2))
-  call assert_equal(s:var3, json_decode(s:json3))
+  call assert_equal(s:var3, s:json3->json_decode())
   call assert_equal(s:var4, json_decode(s:json4))
   call assert_equal(s:var5, json_decode(s:json5))
 
@@ -188,7 +188,7 @@ let s:varl5 = [7, v:none, v:none]
 func Test_js_encode()
   call assert_equal(s:json1, js_encode(s:var1))
   call assert_equal(s:json2, js_encode(s:var2))
-  call assert_equal(s:json3, js_encode(s:var3))
+  call assert_equal(s:json3, s:var3->js_encode())
   call assert_equal(s:json4, js_encode(s:var4))
   call assert_equal(s:json5, js_encode(s:var5))
 
@@ -226,7 +226,7 @@ endfunc
 func Test_js_decode()
   call assert_equal(s:var1, js_decode(s:json1))
   call assert_equal(s:var2, js_decode(s:json2))
-  call assert_equal(s:var3, js_decode(s:json3))
+  call assert_equal(s:var3, s:json3->js_decode())
   call assert_equal(s:var4, js_decode(s:json4))
   call assert_equal(s:var5, js_decode(s:json5))
 

src/testdir/test_lispwords.vim

@@ -43,6 +43,9 @@ func Test_lisp_indent()
 	      \ ',@body',
 	      \ '(princ "</a>")))'
 	      \ ])
+  call assert_equal(7, lispindent(2))
+  call assert_equal(5, 6->lispindent())
+
   set lisp
   set lispwords&
   let save_copt = &cpoptions

src/testdir/test_listener.vim

@@ -59,10 +59,10 @@ func Test_listening()
   " a change above a previous change without a line number change is reported
   " together
   call setline(1, ['one one', 'two'])
-  call listener_flush()
+  call listener_flush(bufnr())
   call append(2, 'two two')
   call setline(1, 'something')
-  call listener_flush()
+  call bufnr()->listener_flush()
   call assert_equal([{'lnum': 3, 'end': 3, 'col': 1, 'added': 1},
 	\ {'lnum': 1, 'end': 2, 'col': 1, 'added': 0}], s:list)
 
@@ -134,7 +134,7 @@ func Test_listening()
   redraw
   call assert_equal([{'lnum': 1, 'end': 2, 'col': 1, 'added': 0}], s:list3)
 
-  call listener_remove(id)
+  eval id->listener_remove()
   bwipe!
 endfunc
 
@@ -214,7 +214,7 @@ func Test_listening_other_buf()
   call setline(1, ['one', 'two'])
   let bufnr = bufnr('')
   normal ww
-  let id = listener_add(function('s:StoreBufList'), bufnr)
+  let id = bufnr->listener_add(function('s:StoreBufList'))
   let s:list = []
   call setbufline(bufnr, 1, 'hello')
   redraw

src/testdir/test_lua.vim

@@ -36,7 +36,7 @@ func Test_eval()
 
   " lua.eval with a string
   lua v = vim.eval('"abc"')
-  call assert_equal('string', luaeval('vim.type(v)'))
+  call assert_equal('string', 'vim.type(v)'->luaeval())
   call assert_equal('abc', luaeval('v'))
 
   " lua.eval with a list

src/testdir/test_utf8.vim

@@ -77,7 +77,7 @@ func Test_list2str_str2list_utf8()
   let s = "\u304b\u3099\u3044"
   let l = [0x304b, 0x3099, 0x3044]
   call assert_equal(l, str2list(s, 1))
-  call assert_equal(s, list2str(l, 1))
+  call assert_equal(s, l->list2str(1))
   if &enc ==# 'utf-8'
     call assert_equal(str2list(s), str2list(s, 1))
     call assert_equal(list2str(l), list2str(l, 1))

src/version.c

@@ -761,6 +761,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1954,
 /**/
     1953,
 /**/