feat(eval/method): partially port v8.1.1996

Problem:    More functions can be used as methods.
Solution:   Make various functions usable as a method.
https://github.com/vim/vim/commit/aad222c9c9a1e4fe6ae5a1fe95bb084619be0e65

Partial port as this does not include eval.txt change for listener_add.

Cherry-pick eval.txt changes for:
- bufadd from v8.1.1626:
  https://github.com/vim/vim/commit/5ca1ac373ae62b37152cb6f85916b402eda520a5
- setloclist and setqflist headers from:
  https://github.com/vim/vim/commit/b0d45e7f5354375edd02afafde3bd37dac1515ff

Correct eval.txt typo for settabwinvar method call (matches latest Vim).

12 files changed, 71 insertions, 32 deletions

diff --git a/runtime/doc/eval.txt b/runtime/doc/eval.txt
index 74b0351dbe..bbd3226d4c 100644
--- a/runtime/doc/eval.txt
+++ b/runtime/doc/eval.txt
@@ -2992,7 +2992,11 @@ bufadd({name})						*bufadd()*
 		number.  Otherwise return the buffer number of the newly
 		created buffer.  When {name} is an empty string then a new
 		buffer is always created.
-		The buffer will not have' 'buflisted' set.
+		The buffer will not have 'buflisted' set and not be loaded
+		yet.  To add some text to the buffer use this: >
+			let bufnr = bufadd('someName')
+			call bufload(bufnr)
+			call setbufline(bufnr, 1, ['some', 'text'])
 <		Can also be used as a |method|: >
 			let bufnr = 'somename'->bufadd()
 
@@ -8704,7 +8708,7 @@ setline({lnum}, {text})					*setline()*
 		Can also be used as a |method|, passing the text as the base: >
 			GetText()->setline(lnum)
 
-setloclist({nr}, {list}[, {action}[, {what}]])		*setloclist()*
+setloclist({nr}, {list} [, {action} [, {what}]])		*setloclist()*
 		Create or replace or add to the location list for window {nr}.
 		{nr} can be the window number or the |window-ID|.
 		When {nr} is zero the current window is used.
@@ -8720,6 +8724,10 @@ setloclist({nr}, {list}[, {action}[, {what}]])		*setloclist()*
 		only the items listed in {what} are set. Refer to |setqflist()|
 		for the list of supported keys in {what}.
 
+		Can also be used as a |method|, the base is passed as the
+		second argument: >
+			GetLoclist()->setloclist(winnr)
+
 setmatches({list} [, {win}])				*setmatches()*
 		Restores a list of matches saved by |getmatches() for the
 		current window|.  Returns 0 if successful, otherwise -1.  All
@@ -8728,6 +8736,9 @@ setmatches({list} [, {win}])				*setmatches()*
 		If {win} is specified, use the window with this number or
 		window ID instead of the current window.
 
+		Can also be used as a |method|: >
+			GetMatches()->setmatches()
+<
 							*setpos()*
 setpos({expr}, {list})
 		Set the position for String {expr}.  Possible values:
@@ -8777,8 +8788,10 @@ setpos({expr}, {list})
 		also set the preferred column.  Also see the "curswant" key in
 		|winrestview()|.
 
+		Can also be used as a |method|: >
+			GetPosition()->setpos('.')
 
-setqflist({list} [, {action}[, {what}]])		*setqflist()*
+setqflist({list} [, {action} [, {what}]])		*setqflist()*
 		Create or replace or add to the quickfix list.
 
 		If the optional {what} dictionary argument is supplied, then
@@ -8887,7 +8900,10 @@ setqflist({list} [, {action}[, {what}]])		*setqflist()*
 		independent of the 'errorformat' setting.  Use a command like
 		`:cc 1` to jump to the first position.
 
-
+		Can also be used as a |method|, the base is passed as the
+		second argument: >
+			GetErrorlist()->setqflist()
+<
 							*setreg()*
 setreg({regname}, {value} [, {options}])
 		Set the register {regname} to {value}.
@@ -8944,6 +8960,10 @@ setreg({regname}, {value} [, {options}])
 		nothing: >
 			:call setreg('a', '', 'al')
 
+<		Can also be used as a |method|, the base is passed as the
+		second argument: >
+			GetText()->setreg('a')
+
 settabvar({tabnr}, {varname}, {val})			*settabvar()*
 		Set tab-local variable {varname} to {val} in tab page {tabnr}.
 		|t:var|
@@ -8952,6 +8972,9 @@ settabvar({tabnr}, {varname}, {val})			*settabvar()*
 		Tabs are numbered starting with one.
 		This function is not available in the |sandbox|.
 
+		Can also be used as a |method|, the base is used as the value: >
+			GetValue()->settabvar(tab, name)
+
 settabwinvar({tabnr}, {winnr}, {varname}, {val})	*settabwinvar()*
 		Set option or local variable {varname} in window {winnr} to
 		{val}.
@@ -8968,6 +8991,9 @@ settabwinvar({tabnr}, {winnr}, {varname}, {val})	*settabwinvar()*
 			:call settabwinvar(3, 2, "myvar", "foobar")
 <		This function is not available in the |sandbox|.
 
+		Can also be used as a |method|, the base is used as the value: >
+			GetValue()->settabwinvar(tab, winnr, name)
+
 settagstack({nr}, {dict} [, {action}])			*settagstack()*
 		Modify the tag stack of the window {nr} using {dict}.
 		{nr} can be the window number or the |window-ID|.
@@ -9001,6 +9027,8 @@ settagstack({nr}, {dict} [, {action}])			*settagstack()*
 			call settagstack(1003, stack)
 			unlet stack
 <
+		Can also be used as a |method|, the base is used as the Dict: >
+			GetStack()->settagstack(winnr)
 
 setwinvar({nr}, {varname}, {val})			*setwinvar()*
 		Like |settabwinvar()| for the current tab page.
@@ -9008,10 +9036,16 @@ setwinvar({nr}, {varname}, {val})			*setwinvar()*
 			:call setwinvar(1, "&list", 0)
 			:call setwinvar(2, "myvar", "foobar")
 
+<		Can also be used as a |method|, the base is used as the value: >
+			GetValue()->setwinvar(winnr, name)
+
 sha256({string})						*sha256()*
 		Returns a String with 64 hex characters, which is the SHA256
 		checksum of {string}.
 
+		Can also be used as a |method|: >
+			GetText()->sha256()
+
 shellescape({string} [, {special}])			*shellescape()*
 		Escape {string} for use as a shell command argument.
 
@@ -9043,6 +9077,8 @@ shellescape({string} [, {special}])			*shellescape()*
 		    :call system("chmod +w -- " . shellescape(expand("%")))
 <		See also |::S|.
 
+		Can also be used as a |method|: >
+			GetCommand()->shellescape()
 
 shiftwidth([{col}])						*shiftwidth()*
 		Returns the effective value of 'shiftwidth'. This is the
@@ -9065,6 +9101,9 @@ shiftwidth([{col}])						*shiftwidth()*
 		'vartabstop' feature. If no {col} argument is given, column 1
 		will be assumed.
 
+		Can also be used as a |method|: >
+			GetColumn()->shiftwidth()
+
 sign_ functions are documented here: |sign-functions-details|
 
 simplify({filename})					*simplify()*
diff --git a/src/nvim/eval.lua b/src/nvim/eval.lua
index 78c4b1ee4d..6a800e5648 100644
--- a/src/nvim/eval.lua
+++ b/src/nvim/eval.lua
@@ -314,18 +314,18 @@ return {
     setenv={args=2, base=2},
     setfperm={args=2, base=1},
     setline={args=2, base=2},
-    setloclist={args={2, 4}},
-    setmatches={args={1, 2}},
-    setpos={args=2},
-    setqflist={args={1, 3}},
-    setreg={args={2, 3}},
-    settabvar={args=3},
-    settabwinvar={args=4},
-    settagstack={args={2, 3}},
-    setwinvar={args=3},
-    sha256={args=1},
-    shellescape={args={1, 2}},
-    shiftwidth={args={0, 1}},
+    setloclist={args={2, 4}, base=2},
+    setmatches={args={1, 2}, base=1},
+    setpos={args=2, base=2},
+    setqflist={args={1, 3}, base=1},
+    setreg={args={2, 3}, base=2},
+    settabvar={args=3, base=3},
+    settabwinvar={args=4, base=4},
+    settagstack={args={2, 3}, base=2},
+    setwinvar={args=3, base=3},
+    sha256={args=1, base=1},
+    shellescape={args={1, 2}, base=1},
+    shiftwidth={args={0, 1}, base=1},
     sign_define={args={1, 2}, base=1},
     sign_getdefined={args={0, 1}, base=1},
     sign_getplaced={args={0, 2}, base=1},
diff --git a/src/nvim/testdir/test_bufwintabinfo.vim b/src/nvim/testdir/test_bufwintabinfo.vim
index c04c8fbf60..d2c99563d9 100644
--- a/src/nvim/testdir/test_bufwintabinfo.vim
+++ b/src/nvim/testdir/test_bufwintabinfo.vim
@@ -48,7 +48,7 @@ function Test_getbufwintabinfo()
   tabnew | let w3_id = win_getid()
   new | let w4_id = win_getid()
   vert new | let w5_id = win_getid()
-  call setwinvar(0, 'signal', 'green')
+  eval 'green'->setwinvar(0, 'signal')
   tabfirst
   let winlist = getwininfo()
   call assert_equal(5, len(winlist))
diff --git a/src/nvim/testdir/test_cursor_func.vim b/src/nvim/testdir/test_cursor_func.vim
index a2482d95c4..d96a35ef53 100644
--- a/src/nvim/testdir/test_cursor_func.vim
+++ b/src/nvim/testdir/test_cursor_func.vim
@@ -37,7 +37,7 @@ endfunc
 " Very short version of what matchparen does.
 function s:Highlight_Matching_Pair()
   let save_cursor = getcurpos()
-  call setpos('.', save_cursor)
+  eval save_cursor->setpos('.')
 endfunc
 
 func Test_curswant_with_autocommand()
diff --git a/src/nvim/testdir/test_expr.vim b/src/nvim/testdir/test_expr.vim
index 6343c47fde..a8cf6577f6 100644
--- a/src/nvim/testdir/test_expr.vim
+++ b/src/nvim/testdir/test_expr.vim
@@ -493,7 +493,7 @@ func Test_setmatches()
     let set[0]['conceal'] = 5
     let exp[0]['conceal'] = '5'
   endif
-  call setmatches(set)
+  eval set->setmatches()
   call assert_equal(exp, getmatches())
 endfunc
 
diff --git a/src/nvim/testdir/test_functions.vim b/src/nvim/testdir/test_functions.vim
index 2fcdd94188..ef33cd5dd8 100644
--- a/src/nvim/testdir/test_functions.vim
+++ b/src/nvim/testdir/test_functions.vim
@@ -1219,7 +1219,7 @@ func Test_shellescape()
   let save_shell = &shell
   set shell=bash
   call assert_equal("'text'", shellescape('text'))
-  call assert_equal("'te\"xt'", shellescape('te"xt'))
+  call assert_equal("'te\"xt'", 'te"xt'->shellescape())
   call assert_equal("'te'\\''xt'", shellescape("te'xt"))
 
   call assert_equal("'te%xt'", shellescape("te%xt"))
diff --git a/src/nvim/testdir/test_put.vim b/src/nvim/testdir/test_put.vim
index 8d8cc77025..f42b177c50 100644
--- a/src/nvim/testdir/test_put.vim
+++ b/src/nvim/testdir/test_put.vim
@@ -39,7 +39,7 @@ func Test_put_lines()
   call assert_equal(['Line 3', '', 'Line 1', 'Line2'], getline(1, '$'))
   " clean up
   bw!
-  call setreg('a', a[0], a[1])
+  eval a[0]->setreg('a', a[1])
 endfunc
 
 func Test_put_expr()
diff --git a/src/nvim/testdir/test_quickfix.vim b/src/nvim/testdir/test_quickfix.vim
index b38a59e98f..6db679c5f9 100644
--- a/src/nvim/testdir/test_quickfix.vim
+++ b/src/nvim/testdir/test_quickfix.vim
@@ -811,7 +811,7 @@ func Test_locationlist()
       " NOTE: problem 1:
       " intentionally not setting 'lnum' so that the quickfix entries are not
       " valid
-      call setloclist(0, qflist, ' ')
+      eval qflist->setloclist(0, ' ')
     endfor
 
     " Test A
@@ -1699,7 +1699,7 @@ endfunc
 
 func Test_setqflist_invalid_nr()
   " The following command used to crash Vim
-  call setqflist([], ' ', {'nr' : $XXX_DOES_NOT_EXIST})
+  eval []->setqflist(' ', {'nr' : $XXX_DOES_NOT_EXIST})
 endfunc
 
 func Test_setqflist_user_sets_buftype()
diff --git a/src/nvim/testdir/test_sha256.vim b/src/nvim/testdir/test_sha256.vim
index dd4707977e..76d1306836 100644
--- a/src/nvim/testdir/test_sha256.vim
+++ b/src/nvim/testdir/test_sha256.vim
@@ -6,17 +6,17 @@ endif
 
 function Test_sha256()
   " test for empty string:
-  call assert_equal(sha256(""), 'e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855')
+  call assert_equal('e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855', sha256(""))
 
   "'test for 1 char:
-  call assert_equal(sha256("a"), 'ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb')
+  call assert_equal('ca978112ca1bbdcafac231b39a23dc4da786eff8147c4e72b9807785afee48bb', sha256("a"))
   "
   "test for 3 chars:
-  call assert_equal(sha256("abc"), 'ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad')
+  call assert_equal('ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad', "abc"->sha256())
 
   " test for contains meta char:
-  call assert_equal(sha256("foo\nbar"), '807eff6267f3f926a21d234f7b0cf867a86f47e07a532f15e8cc39ed110ca776')
+  call assert_equal('807eff6267f3f926a21d234f7b0cf867a86f47e07a532f15e8cc39ed110ca776', sha256("foo\nbar"))
 
   " test for contains non-ascii char:
-  call assert_equal(sha256("\xde\xad\xbe\xef"), '5f78c33274e43fa9de5659265c1d917e25c03722dcb0b8d27db8d5feaa813953')
+  call assert_equal('5f78c33274e43fa9de5659265c1d917e25c03722dcb0b8d27db8d5feaa813953', sha256("\xde\xad\xbe\xef"))
 endfunction
diff --git a/src/nvim/testdir/test_tabpage.vim b/src/nvim/testdir/test_tabpage.vim
index b261b96c3b..9869dc7590 100644
--- a/src/nvim/testdir/test_tabpage.vim
+++ b/src/nvim/testdir/test_tabpage.vim
@@ -35,7 +35,7 @@ function Test_tabpage()
   tabnew
   tabfirst
   call settabvar(2, 'val_num', 100)
-  call settabvar(2, 'val_str', 'SetTabVar test')
+  eval 'SetTabVar test'->settabvar(2, 'val_str')
   call settabvar(2, 'val_list', ['red', 'blue', 'green'])
   "
   call assert_true(gettabvar(2, 'val_num') == 100 && gettabvar(2, 'val_str') == 'SetTabVar test' && gettabvar(2, 'val_list') == ['red', 'blue', 'green'])
@@ -184,7 +184,7 @@ function Test_tabpage_with_autocmd()
   let s:li = split(join(map(copy(winr), 'gettabwinvar('.tabn.', v:val, "a")')), '\s\+')
   call assert_equal(['a', 'a'], s:li)
   let s:li = []
-  C call map(copy(winr), 'settabwinvar('.tabn.', v:val, ''a'', v:val*2)')
+  C call map(copy(winr), '(v:val*2)->settabwinvar(' .. tabn .. ', v:val, ''a'')')
   let s:li = split(join(map(copy(winr), 'gettabwinvar('.tabn.', v:val, "a")')), '\s\+')
   call assert_equal(['2', '4'], s:li)
 
diff --git a/src/nvim/testdir/test_tagjump.vim b/src/nvim/testdir/test_tagjump.vim
index 15182893e9..2aa04df42a 100644
--- a/src/nvim/testdir/test_tagjump.vim
+++ b/src/nvim/testdir/test_tagjump.vim
@@ -351,7 +351,7 @@ func Test_getsettagstack()
   " Try to set current index to invalid values
   call settagstack(1, {'curidx' : -1})
   call assert_equal(1, gettagstack().curidx)
-  call settagstack(1, {'curidx' : 50})
+  eval {'curidx' : 50}->settagstack(1)
   call assert_equal(4, gettagstack().curidx)
 
   " Try pushing invalid items onto the stack
diff --git a/src/nvim/testdir/test_vartabs.vim b/src/nvim/testdir/test_vartabs.vim
index 2fbf130345..46e0d62313 100644
--- a/src/nvim/testdir/test_vartabs.vim
+++ b/src/nvim/testdir/test_vartabs.vim
@@ -330,7 +330,7 @@ func Test_vartabs_shiftwidth()
   let lines = ScreenLines([1, 2], winwidth(0))
   call s:compare_lines(expect2, lines)
   call assert_equal(20, shiftwidth(virtcol('.')-2))
-  call assert_equal(30, shiftwidth(virtcol('.')))
+  call assert_equal(30, virtcol('.')->shiftwidth())
   norm! $>>
   let expect3 = ['                                        ', '                    x                   ', '~                                       ']
   let lines = ScreenLines([1, 3], winwidth(0))