patch 9.0.2057: Vim9: no strict type checks for funcrefs varargs
Problem: Vim9: no strict type checks for funcrefs varargs
Solution: Perform strict type checking when declaring funcrefs
with vararg declaration, add tests
closes: #13397
Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Ernie Rael <errael@raelity.com>
diff --git a/runtime/doc/vim9.txt b/runtime/doc/vim9.txt
index 6cabb87..58d9ed6 100644
--- a/runtime/doc/vim9.txt
+++ b/runtime/doc/vim9.txt
@@ -1468,7 +1468,7 @@
There is no array type, use list<{type}> instead. For a list constant an
efficient implementation is used that avoids allocating a lot of small pieces
of memory.
- *E1005* *E1007*
+ *vim9-func-declaration* *E1005* *E1007*
A partial and function can be declared in more or less specific ways:
func any kind of function reference, no type
checking for arguments or return value
@@ -1669,6 +1669,26 @@
|flattennew()| instead. Since |flatten()| is intended to always change the
type, it can not be used in Vim9 script.
+Assigning to a funcref with specified arguments (see |vim9-func-declaration|)
+does strict type checking of the arguments. For variable number of arguments
+the type must match: >
+ var FuncRef: func(string, number, bool): number
+ FuncRef = (v1: string, v2: number, v3: bool) => 777 # OK
+ FuncRef = (v1: string, v2: number, v3: number) => 777 # Error!
+ # variable number of arguments must have same type
+ var FuncVA: func(...list<string>): number
+ FuncVA = (...v: list<number>): number => v # Error!
+ FuncVA = (...v: list<any>): number => v # OK, `any` runtime check
+ FuncVA = (v1: string, v: string2): number => 333 # Error!
+ FuncVA = (v: list<string>): number => 3 # Error!
+
+If the destinataion funcref has no specified arguments, then there is no
+argument type checking: >
+ var FuncUnknownArgs: func: number
+ FuncUnknownArgs = (v): number => v # OK
+ FuncUnknownArgs = (v1: string, v2: string): number => 3 # OK
+< FuncUnknownArgs = (...v1: list<string>): number => 333 # OK
+
*E1211* *E1217* *E1218* *E1219* *E1220* *E1221*
*E1222* *E1223* *E1224* *E1225* *E1226* *E1227*
*E1228* *E1238* *E1250* *E1251* *E1252* *E1256*