text/template: fix variadic function call corner case
Executing a template involving variadic functions featuring
a []interface{} slice (such as printf) could result in a
panic in reflect.Value.Call, due to incorrect type checking.
The following expressions failed (with a panic):
{{true|printf}}
{{1|printf}}
{{1.1|printf}}
{{'x'|printf}}
{{1+2i|printf}}
Implemented proper type checks for the fixed parameters of the
variadic functions.
Fixes #10946
Change-Id: Ia75333f651f73b3d2e024cb0c47cc30d90cb6852
Reviewed-on: https://go-review.googlesource.com/10403
Reviewed-by: Rob Pike <r@golang.org>
diff --git a/src/text/template/exec_test.go b/src/text/template/exec_test.go
index 0f1ad62..f083547 100644
--- a/src/text/template/exec_test.go
+++ b/src/text/template/exec_test.go
@@ -533,6 +533,18 @@
{"bug14c", `{{$x := (1.0)}}{{$y := ("hello")}}{{$x.anything}}{{$y.true}}`, "", tVal, false},
// Didn't call validateType on function results. Issue 10800.
{"bug15", "{{valueString returnInt}}", "", tVal, false},
+ // Variadic function corner cases. Issue 10946.
+ {"bug16a", "{{true|printf}}", "", tVal, false},
+ {"bug16b", "{{1|printf}}", "", tVal, false},
+ {"bug16c", "{{1.1|printf}}", "", tVal, false},
+ {"bug16d", "{{'x'|printf}}", "", tVal, false},
+ {"bug16e", "{{0i|printf}}", "", tVal, false},
+ {"bug16f", "{{true|twoArgs \"xxx\"}}", "", tVal, false},
+ {"bug16g", "{{\"aaa\" |twoArgs \"bbb\"}}", "twoArgs=bbbaaa", tVal, true},
+ {"bug16h", "{{1|oneArg}}", "", tVal, false},
+ {"bug16i", "{{\"aaa\"|oneArg}}", "oneArg=aaa", tVal, true},
+ {"bug16j", "{{1+2i|printf \"%v\"}}", "(1+2i)", tVal, true},
+ {"bug16k", "{{\"aaa\"|printf }}", "aaa", tVal, true},
}
func zeroArgs() string {
@@ -543,6 +555,10 @@
return "oneArg=" + a
}
+func twoArgs(a, b string) string {
+ return "twoArgs=" + a + b
+}
+
func dddArg(a int, b ...string) string {
return fmt.Sprintln(a, b)
}
@@ -620,6 +636,7 @@
"oneArg": oneArg,
"returnInt": returnInt,
"stringer": stringer,
+ "twoArgs": twoArgs,
"typeOf": typeOf,
"valueString": valueString,
"vfunc": vfunc,
