diff --git a/src/text/template/multi_test.go b/src/text/template/multi_test.go index 8142f008fd..5d8c08f06f 100644 --- a/src/text/template/multi_test.go +++ b/src/text/template/multi_test.go @@ -363,7 +363,7 @@ func TestEmptyTemplate(t *testing.T) { {[]string{"{{.}}", ""}, "twice", ""}, } - for _, c := range cases { + for i, c := range cases { root := New("root") var ( @@ -378,10 +378,43 @@ func TestEmptyTemplate(t *testing.T) { } buf := &bytes.Buffer{} if err := m.Execute(buf, c.in); err != nil { - t.Fatal(err) + t.Error(i, err) + continue } if buf.String() != c.want { t.Errorf("expected string %q: got %q", c.want, buf.String()) } } } + +// Issue 19249 was a regression in 1.8 caused by the handling of empty +// templates added in that release, which got different answers depending +// on the order templates appeared in the internal map. +func TestIssue19294(t *testing.T) { + // The empty block in "xhtml" should be replaced during execution + // by the contents of "stylesheet", but if the internal map associating + // names with templates is built in the wrong order, the empty block + // looks non-empty and this doesn't happen. + var inlined = map[string]string{ + "stylesheet": `{{define "stylesheet"}}stylesheet{{end}}`, + "xhtml": `{{block "stylesheet" .}}{{end}}`, + } + all := []string{"stylesheet", "xhtml"} + for i := 0; i < 100; i++ { + res, err := New("title.xhtml").Parse(`{{template "xhtml" .}}`) + if err != nil { + t.Fatal(err) + } + for _, name := range all { + _, err := res.New(name).Parse(inlined[name]) + if err != nil { + t.Fatal(err) + } + } + var buf bytes.Buffer + res.Execute(&buf, 0) + if buf.String() != "stylesheet" { + t.Fatalf("iteration %d: got %q; expected %q", i, buf.String(), "stylesheet") + } + } +} diff --git a/src/text/template/template.go b/src/text/template/template.go index b6fceb1795..3b4f34b4db 100644 --- a/src/text/template/template.go +++ b/src/text/template/template.go @@ -127,7 +127,7 @@ func (t *Template) AddParseTree(name string, tree *parse.Tree) (*Template, error // Even if nt == t, we need to install it in the common.tmpl map. if replace, err := t.associate(nt, tree); err != nil { return nil, err - } else if replace { + } else if replace || nt.Tree == nil { nt.Tree = tree } return nt, nil @@ -215,7 +215,7 @@ func (t *Template) associate(new *Template, tree *parse.Tree) (bool, error) { if new.common != t.common { panic("internal error: associate not common") } - if t.tmpl[new.name] != nil && parse.IsEmptyTree(tree.Root) && t.Tree != nil { + if old := t.tmpl[new.name]; old != nil && parse.IsEmptyTree(tree.Root) && old.Tree != nil { // If a template by that name exists, // don't replace it with an empty template. return false, nil