From: Rob Pike <r@golang.org>
Date: Mon, 30 Sep 2019 23:54:30 +0000 (+1000)
Subject: text/template: further simplify building the vars list
X-Git-Tag: go1.14beta1~912
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=27cf81e1b48efe6a6387f34c7114766c7b0d4d73;p=gostls13.git

text/template: further simplify building the vars list

Followup to https://golang.org/cl/197997

If you know the number of elements, you don't need append at all.
Either use append to grow, or allocate and index. Here we choose
number 2.

Change-Id: Ic58637231789640ff7b293ece04a95a8de7ccf8f
Reviewed-on: https://go-review.googlesource.com/c/go/+/198097
Reviewed-by: Ian Lance Taylor <iant@golang.org>
---

diff --git a/src/text/template/parse/node.go b/src/text/template/parse/node.go
index 74552c293f..2f921be2ec 100644
--- a/src/text/template/parse/node.go
+++ b/src/text/template/parse/node.go
@@ -187,9 +187,9 @@ func (p *PipeNode) CopyPipe() *PipeNode {
 	if p == nil {
 		return p
 	}
-	vars := make([]*VariableNode, 0, len(p.Decl))
-	for _, d := range p.Decl {
-		vars = append(vars, d.Copy().(*VariableNode))
+	vars := make([]*VariableNode, len(p.Decl))
+	for i, d := range p.Decl {
+		vars[i] = d.Copy().(*VariableNode)
 	}
 	n := p.tr.newPipeline(p.Pos, p.Line, vars)
 	n.IsAssign = p.IsAssign