text/template/parse: fix handling of assignment/declaration in PipeNode.String
The String method for Pipes assumed all variables were declared. Easy fix:
check the IsAssign bit.
Fixes #65382
Change-Id: I58f2760c1a8bb2821c3538645d893f58fd76ae73
Reviewed-on: https://go-review.googlesource.com/c/go/+/592695
Run-TryBot: Rob Pike <r@golang.org> Reviewed-by: David Chase <drchase@google.com> Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Rob Pike <r@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
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Auto-Submit: Ian Lance Taylor <iant@google.com>