patch 8.1.1909: more functions can be used as methods

Problem:    More functions can be used as methods.
Solution:   Make a few more functions usable as a method.
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 62938c1..b154840 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -431,7 +431,7 @@
 #endif
     {"assert_beeps",	1, 2, FEARG_1,	  f_assert_beeps},
     {"assert_equal",	2, 3, FEARG_2,	  f_assert_equal},
-    {"assert_equalfile", 2, 2, 0,	  f_assert_equalfile},
+    {"assert_equalfile", 2, 2, FEARG_1,	  f_assert_equalfile},
     {"assert_exception", 1, 2, 0,	  f_assert_exception},
     {"assert_fails",	1, 3, FEARG_1,	  f_assert_fails},
     {"assert_false",	1, 2, FEARG_1,	  f_assert_false},
@@ -439,7 +439,7 @@
     {"assert_match",	2, 3, FEARG_2,	  f_assert_match},
     {"assert_notequal",	2, 3, FEARG_2,	  f_assert_notequal},
     {"assert_notmatch",	2, 3, FEARG_2,	  f_assert_notmatch},
-    {"assert_report",	1, 1, 0,	  f_assert_report},
+    {"assert_report",	1, 1, FEARG_1,	  f_assert_report},
     {"assert_true",	1, 2, FEARG_1,	  f_assert_true},
 #ifdef FEAT_FLOAT
     {"atan",		1, 1, FEARG_1,	  f_atan},
@@ -464,8 +464,8 @@
     {"bufloaded",	1, 1, FEARG_1,	  f_bufloaded},
     {"bufname",		1, 1, FEARG_1,	  f_bufname},
     {"bufnr",		1, 2, FEARG_1,	  f_bufnr},
-    {"bufwinid",	1, 1, 0,	  f_bufwinid},
-    {"bufwinnr",	1, 1, 0,	  f_bufwinnr},
+    {"bufwinid",	1, 1, FEARG_1,	  f_bufwinid},
+    {"bufwinnr",	1, 1, FEARG_1,	  f_bufwinnr},
     {"byte2line",	1, 1, 0,	  f_byte2line},
     {"byteidx",		2, 2, 0,	  f_byteidx},
     {"byteidxcomp",	2, 2, 0,	  f_byteidxcomp},
@@ -963,7 +963,7 @@
     {"win_id2tabwin",	1, 1, 0,	  f_win_id2tabwin},
     {"win_id2win",	1, 1, 0,	  f_win_id2win},
     {"win_screenpos",	1, 1, 0,	  f_win_screenpos},
-    {"winbufnr",	1, 1, 0,	  f_winbufnr},
+    {"winbufnr",	1, 1, FEARG_1,	  f_winbufnr},
     {"wincol",		0, 0, 0,	  f_wincol},
     {"winheight",	1, 1, 0,	  f_winheight},
     {"winlayout",	0, 1, 0,	  f_winlayout},
diff --git a/src/testdir/test_assert.vim b/src/testdir/test_assert.vim
index 65a0ee4..d89bd98 100644
--- a/src/testdir/test_assert.vim
+++ b/src/testdir/test_assert.vim
@@ -54,7 +54,7 @@
 
   let goodtext = ["one", "two", "three"]
   call writefile(goodtext, 'Xone')
-  call assert_equal(1, assert_equalfile('Xone', 'xyzxyz'))
+  call assert_equal(1, 'Xone'->assert_equalfile('xyzxyz'))
   call assert_match("E485: Can't read file xyzxyz", v:errors[0])
   call remove(v:errors, 0)
 
@@ -97,6 +97,9 @@
   call assert_equal(1, assert_report('something is wrong'))
   call assert_match('something is wrong', v:errors[0])
   call remove(v:errors, 0)
+  call assert_equal(1, 'also wrong'->assert_report())
+  call assert_match('also wrong', v:errors[0])
+  call remove(v:errors, 0)
 endfunc
 
 func Test_assert_exception()
diff --git a/src/testdir/test_bufline.vim b/src/testdir/test_bufline.vim
index a6b4694..6d62e51 100644
--- a/src/testdir/test_bufline.vim
+++ b/src/testdir/test_bufline.vim
@@ -152,11 +152,11 @@
 
   let lines =<< trim END
     new foo
-    let winnr=bufwinnr('foo')
-    let buf=bufnr('foo')
+    let winnr = 'foo'->bufwinnr()
+    let buf = bufnr('foo')
     wincmd p
     call appendbufline(buf, '$', range(1,200))
-    exe winnr. 'wincmd w'
+    exe winnr .. 'wincmd w'
     norm! G
     wincmd p
     call deletebufline(buf, 1, '$')
diff --git a/src/testdir/test_bufwintabinfo.vim b/src/testdir/test_bufwintabinfo.vim
index 0e8c7d1..7f0a6ce 100644
--- a/src/testdir/test_bufwintabinfo.vim
+++ b/src/testdir/test_bufwintabinfo.vim
@@ -18,7 +18,7 @@
     let l = getbufinfo('%')
     call assert_equal(bufnr('%'), l[0].bufnr)
     call assert_equal('vim', l[0].variables.editor)
-    call assert_notequal(-1, index(l[0].windows, bufwinid('%')))
+    call assert_notequal(-1, index(l[0].windows, '%'->bufwinid()))
 
     " Test for getbufinfo() with 'bufmodified'
     call assert_equal(0, len(getbufinfo({'bufmodified' : 1})))
diff --git a/src/testdir/test_popupwin.vim b/src/testdir/test_popupwin.vim
index f742035..23041d1 100644
--- a/src/testdir/test_popupwin.vim
+++ b/src/testdir/test_popupwin.vim
@@ -2332,8 +2332,7 @@
 endfunc
 
 func Test_popupwin_recycle_bnr()
-  let winid = popup_notification('nothing wrong', {})
-  let bufnr = winbufnr(winid)
+  let bufnr = popup_notification('nothing wrong', {})->winbufnr()
   call popup_clear()
   let winid = popup_notification('nothing wrong', {})
   call assert_equal(bufnr, winbufnr(winid))
diff --git a/src/version.c b/src/version.c
index a6544cd..37b0f79 100644
--- a/src/version.c
+++ b/src/version.c
@@ -762,6 +762,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1909,
+/**/
     1908,
 /**/
     1907,