patch 8.2.1710: Vim9: list of list type can be wrong
Problem: Vim9: list of list type can be wrong.
Solution: Use VAR_UNKNOWN for empty list. Recognize VAR_UNKNOWN when
looking for a common type. (closes #6979)
diff --git a/src/testdir/test_vim9_expr.vim b/src/testdir/test_vim9_expr.vim
index d79e2cd..b9a6811 100644
--- a/src/testdir/test_vim9_expr.vim
+++ b/src/testdir/test_vim9_expr.vim
@@ -1513,6 +1513,10 @@
2] [3,
4]
+ let llstring: list<list<string>> = [['text'], []]
+ llstring = [[], ['text']]
+ llstring = [[], []]
+
CheckDefFailure(["let x = 1234[3]"], 'E1107:', 1)
CheckDefExecFailure(["let x = g:anint[3]"], 'E1062:', 1)
@@ -1718,6 +1722,14 @@
mixed = #{a: 234}
mixed = #{}
+ let dictlist: dict<list<string>> = #{absent: [], present: ['hi']}
+ dictlist = #{absent: ['hi'], present: []}
+ dictlist = #{absent: [], present: []}
+
+ let dictdict: dict<dict<string>> = #{one: #{a: 'text'}, two: #{}}
+ dictdict = #{one: #{}, two: #{a: 'text'}}
+ dictdict = #{one: #{}, two: #{}}
+
CheckDefFailure(["let x = #{a:8}"], 'E1069:', 1)
CheckDefFailure(["let x = #{a : 8}"], 'E1068:', 1)
CheckDefFailure(["let x = #{a :8}"], 'E1068:', 1)