runtime(vim): Update base-syntax, match ternary and falsy operators

fixes: #14423
fixes: #16227
closes: #16484

Signed-off-by: Doug Kearns <dougkearns@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/syntax/testdir/input/vim9_expr.vim

@@ -2,6 +2,59 @@ vim9script
 # Vim9-script expressions
 
 
+# Operators
+
+# Ternary
+
+echo expr ? expr : expr
+
+echo lnum == 1 ? "top" : lnum
+echo lnum == 1 ? "top" : lnum == 1000 ? "last" : lnum
+
+echo lnum == 1
+	? "top"
+	: lnum == 1000
+		? "last"
+		: lnum
+echo lnum == 1 ?
+	"top" :
+	lnum == 1000 ?
+		"last" :
+		lnum
+
+echo true ? true : false
+echo 1 ? 1 : 0
+echo "foo" ? "foo" : "bar"
+echo foo ? foo : bar
+echo g:foo ? g:foo : g:bar
+echo $FOO ? $FOO : $BAR
+echo True() ? True() : False()
+echo @a ? @a : @b
+echo (1) ? (1) : (0)
+
+# Falsy
+
+echo expr ?? expr
+
+echo theList ?? 'list is empty'
+echo GetName() ?? 'unknown'
+
+echo theList
+      \ ?? 'list is empty'
+echo theList ??
+      \ 'list is empty'
+
+echo true ?? true
+echo 1 ?? 1
+echo "foo" ?? "foo"
+echo foo ?? foo
+echo g:foo ?? g:foo
+echo $FOO ?? $FOO
+echo True() ?? True()
+echo @a ?? @a
+echo (1) ?? (1)
+
+
 # Command {expr} arguments
 
 if true
@@ -18,3 +71,37 @@ def Foo(): bool
   return true
 enddef
 
+
+# Issue #14423 (vim.vim: Opt out of vimSearch*)
+
+:?truthy
+const truthy: number = false
+    ? (0
+    )
+    : (1
+    )
+echo truthy
+
+def Foo()
+  :?truthy
+  const truthy: number = false
+      ? (0
+      )
+      : (1
+      )
+  echo truthy
+enddef
+
+
+# Issue #16227 (Vimscript ternary expression highlighting)
+
+var foo = 'foo'                         # comment
+var bar = foo == 'foo' ? 'bar' : 'baz'
+var baz = foo == 'foo'
+            \ ? 'baz'
+            \ : 'bar'
+var qux = foo == 'foo'
+            ? 'qux'                     # comment
+            : 'qux'                     # comment
+echo qux ?? 'quux'
+