From f30a14db3b26e510f193f50ee0dd8a41303e4740 Mon Sep 17 00:00:00 2001
From: Bram Moolenaar <Bram@vim.org>
Date: Sun, 17 Jan 2021 21:51:24 +0100
Subject: [PATCH] patch 8.2.2373: Vim9: list assignment only accepts a number
 index

Problem:    Vim9: list assignment only accepts a number index.
Solution:   Accept "any" and do a runtime type check. (closes #7694)
---
 src/testdir/test_vim9_assign.vim | 13 +++++++++++--
 src/version.c                    |  2 ++
 src/vim9compile.c                |  7 ++-----
 3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/testdir/test_vim9_assign.vim b/src/testdir/test_vim9_assign.vim
index c03555880..20bdb9138 100644
--- a/src/testdir/test_vim9_assign.vim
+++ b/src/testdir/test_vim9_assign.vim
@@ -350,7 +350,7 @@ def Test_assign_index()
     var lines: list<string>
     lines['a'] = 'asdf'
   END
-  CheckDefFailure(lines, 'E39:', 2)
+  CheckDefFailure(lines, 'E1012:', 2)
 
   lines =<< trim END
     var lines: string
@@ -561,6 +561,15 @@ def Test_assignment_list()
   CheckDefExecFailure(lines, 'E1147:', 2)
 enddef
 
+def Test_assignment_list_any_index()
+   var l: list<number> = [1, 2]
+  for  [x, y, _]
+  in  [[0, 1, ''], [1, 3, '']]
+      l[x] = l[x] + y
+  endfor
+  assert_equal([2, 5], l)
+enddef
+
 def Test_assignment_list_vim9script()
   var lines =<< trim END
     vim9script
@@ -1405,7 +1414,7 @@ def Test_unlet()
   CheckDefExecFailure([
     'var ll = [1]',
     'unlet ll[g:astring]',
-    ], 'E39:', 2)
+    ], 'E1012:', 2)
   CheckDefExecFailure([
     'var dd = test_null_dict()',
     'unlet dd["a"]',
diff --git a/src/version.c b/src/version.c
index 3a88080e0..f1b728048 100644
--- a/src/version.c
+++ b/src/version.c
@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2373,
 /**/
     2372,
 /**/
diff --git a/src/vim9compile.c b/src/vim9compile.c
index 01bf2c19a..d1df00821 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -5802,12 +5802,9 @@ compile_assign_unlet(
 	if (dest_type == VAR_DICT && may_generate_2STRING(-1, cctx) == FAIL)
 	    return FAIL;
 	if (dest_type == VAR_LIST
-		     && ((type_T **)stack->ga_data)[stack->ga_len - 1]->tt_type
-								 != VAR_NUMBER)
-	{
-	    emsg(_(e_number_exp));
+		&& need_type(((type_T **)stack->ga_data)[stack->ga_len - 1],
+				 &t_number, -1, 0, cctx, FALSE, FALSE) == FAIL)
 	    return FAIL;
-	}
     }
 
     // Load the dict or list.  On the stack we then have:
-- 
2.50.1