patch 9.0.0837: append() reports failure when not appending anythingv9.0.0837

Problem:    append() reports failure when not appending anything.
Solution:   Only report failure when appending something. (closes #11498)

5 files changed, 23 insertions, 14 deletions

diff --git a/src/evalbuffer.c b/src/evalbuffer.c
index e77435b8f4..9ce1d41aeb 100644
--- a/src/evalbuffer.c
+++ b/src/evalbuffer.c
@@ -175,9 +175,7 @@ set_buffer_lines(
 	l = lines->vval.v_list;
 	if (l == NULL || list_len(l) == 0)
 	{
-	    // set proper return code
-	    if (lnum > curbuf->b_ml.ml_line_count)
-		rettv->vval.v_number = 1;	// FAIL
+	    // not appending anything always succeeds
 	    goto done;
 	}
 	CHECK_LIST_MATERIALIZE(l);
diff --git a/src/testdir/test_bufline.vim b/src/testdir/test_bufline.vim
index c592877e81..13e891bcf1 100644
--- a/src/testdir/test_bufline.vim
+++ b/src/testdir/test_bufline.vim
@@ -23,8 +23,8 @@ func Test_setbufline_getbufline()
 
   call assert_equal(1, setbufline(b, 5, 'x'))
   call assert_equal(1, setbufline(b, 5, ['x']))
-  call assert_equal(1, setbufline(b, 5, []))
-  call assert_equal(1, setbufline(b, 5, test_null_list()))
+  call assert_equal(0, setbufline(b, 5, []))
+  call assert_equal(0, setbufline(b, 5, test_null_list()))
 
   call assert_equal(1, 'x'->setbufline(bufnr('$') + 1, 1))
   call assert_equal(1, ['x']->setbufline(bufnr('$') + 1, 1))
@@ -86,6 +86,11 @@ func Test_setline_startup()
   sleep 50m
   call assert_equal(['Hello'], readfile('Xtest'))
 
+  call assert_equal(0, setline(1, []))
+  call assert_equal(0, setline(1, test_null_list()))
+  call assert_equal(0, setline(5, []))
+  call assert_equal(0, setline(6, test_null_list()))
+
   call delete('Xtest')
 endfunc
 
@@ -112,8 +117,8 @@ func Test_appendbufline()
 
   call assert_equal(1, appendbufline(b, 4, 'x'))
   call assert_equal(1, appendbufline(b, 4, ['x']))
-  call assert_equal(1, appendbufline(b, 4, []))
-  call assert_equal(1, appendbufline(b, 4, test_null_list()))
+  call assert_equal(0, appendbufline(b, 4, []))
+  call assert_equal(0, appendbufline(b, 4, test_null_list()))
 
   call assert_equal(1, appendbufline(1234, 1, 'x'))
   call assert_equal(1, appendbufline(1234, 1, ['x']))
@@ -122,8 +127,8 @@ func Test_appendbufline()
 
   call assert_equal(0, appendbufline(b, 1, []))
   call assert_equal(0, appendbufline(b, 1, test_null_list()))
-  call assert_equal(1, appendbufline(b, 3, []))
-  call assert_equal(1, appendbufline(b, 3, test_null_list()))
+  call assert_equal(0, appendbufline(b, 3, []))
+  call assert_equal(0, appendbufline(b, 3, test_null_list()))
 
   call assert_equal(['a', 'b', 'c'], getbufline(b, 1, '$'))
 
diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index 831a8946f6..131db109e3 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -939,9 +939,13 @@ endfunc
 func Test_append()
   enew!
   split
-  call append(0, ["foo"])
-  call append(1, [])
-  call append(1, test_null_list())
+  call assert_equal(0, append(1, []))
+  call assert_equal(0, append(1, test_null_list()))
+  call assert_equal(0, append(0, ["foo"]))
+  call assert_equal(0, append(1, []))
+  call assert_equal(0, append(1, test_null_list()))
+  call assert_equal(0, append(8, []))
+  call assert_equal(0, append(9, test_null_list()))
   call assert_equal(['foo', ''], getline(1, '$'))
   split
   only
diff --git a/src/testdir/test_vim9_builtin.vim b/src/testdir/test_vim9_builtin.vim
index e9ec43930e..10ae2eeb03 100644
--- a/src/testdir/test_vim9_builtin.vim
+++ b/src/testdir/test_vim9_builtin.vim
@@ -3721,8 +3721,8 @@ def Test_set_get_bufline()
 
       assert_equal(1, setbufline(b, 5, 'x'))
       assert_equal(1, setbufline(b, 5, ['x']))
-      assert_equal(1, setbufline(b, 5, []))
-      assert_equal(1, setbufline(b, 5, test_null_list()))
+      assert_equal(0, setbufline(b, 5, []))
+      assert_equal(0, setbufline(b, 5, test_null_list()))
 
       assert_equal(1, 'x'->setbufline(bufnr('$') + 1, 1))
       assert_equal(1, ['x']->setbufline(bufnr('$') + 1, 1))
diff --git a/src/version.c b/src/version.c
index 2694639507..56ccb053a2 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    837,
+/**/
     836,
 /**/
     835,