text/template: add detailed info for goodFunc check
goodFunc now returns a error describe the exact error it met.
builtin call function can print the name of the callee function
if the goodFunc check failed.
For input {{call .InvalidReturnCountFunc}}
before:
can't evaluate field InvalidReturnTypeFunc in type *template.T
after:
invalid function signature for .InvalidReturnTypeFunc: second argument should be error; is bool
Change-Id: I9aa53424ac9a2bffbdbeac889390f41218817575
GitHub-Last-Rev:
7c1e0dbd08884a38d92a42530104884a9ca52b44
GitHub-Pull-Request: golang/go#65509
Reviewed-on: https://go-review.googlesource.com/c/go/+/561115
Reviewed-by: Rob Pike <r@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Commit-Queue: Ian Lance Taylor <iant@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>