From 100f65f83af6bef79b86b60b9a618af73fcb0ae5 Mon Sep 17 00:00:00 2001
From: Greg <gmp@wow.st>
Date: Sat, 4 Aug 2018 15:41:34 -0400
Subject: [PATCH] pgen: discover types for composite literals.

---
 cmd/pgen/main.go   | 16 ++++++++++++----
 test/basic/main.go |  2 ++
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/cmd/pgen/main.go b/cmd/pgen/main.go
index 6a3e983..6777c7f 100644
--- a/cmd/pgen/main.go
+++ b/cmd/pgen/main.go
@@ -24,7 +24,7 @@ func (v *visitor) Visit(node ast.Node) ast.Visitor {
 	if !reg.MatchString(id.Name) { return v }
 
 	if len(x.Args) != 2 {
-		log.Fatal("Wrong number of arguments in persist_T call.")
+		log.Fatal("Wrong number of arguments in persistT call.")
 	}
 	var tp string
 	switch arg := x.Args[1].(type) {
@@ -33,14 +33,16 @@ func (v *visitor) Visit(node ast.Node) ast.Visitor {
 		if tp == "float" {
 			tp = "float64"
 		}
+	case *ast.CompositeLit:
+		tp = types.TypeString(info.TypeOf(arg),types.RelativeTo(pkg))
 	case *ast.Ident:
 		if arg.Obj.Kind != ast.Var { return v }
 		inner := pkg.Scope().Innermost(arg.Pos())
 		_,obj := inner.LookupParent(arg.Obj.Name,arg.Pos())
 		tp = types.TypeString(obj.Type(),types.RelativeTo(pkg))
 		trimType(&tp)
-		for _, submatches := range impreg.FindAllStringSubmatchIndex(tp, -1) {
-			pkgname := impreg.ExpandString(make([]byte,0), "$1", tp, submatches)
+		for _, s := range impreg.FindAllStringSubmatchIndex(tp, -1) {
+			pkgname := impreg.ExpandString(make([]byte,0), "$1", tp, s)
 			needImps[string(pkgname)] = true
 		}
 	default:
@@ -63,6 +65,7 @@ var pkgreg *regexp.Regexp
 var impreg *regexp.Regexp
 var imps map[string]string
 var needImps map[string]bool
+var info *types.Info
 
 func chkpkg(p *ast.Package) {
 	fs := make([]*ast.File,0)
@@ -72,7 +75,12 @@ func chkpkg(p *ast.Package) {
 
 	conf := types.Config{Error: func(error) {}, Importer: importer.Default()}
 	var err error
-	pkg, err = conf.Check("main", fset, fs, nil)
+	info = &types.Info{
+		Types:	make(map[ast.Expr]types.TypeAndValue),
+		Defs:	make(map[*ast.Ident]types.Object),
+		Uses:	make(map[*ast.Ident]types.Object)}
+
+	pkg, err = conf.Check("main", fset, fs, info)
 	if err != nil {
 		log.Print("Check:",err)
 	}
diff --git a/test/basic/main.go b/test/basic/main.go
index 054edc4..4550890 100644
--- a/test/basic/main.go
+++ b/test/basic/main.go
@@ -34,6 +34,8 @@ func main() {
 	y6 := make(map[persist.Var]gtoken.FileSet)
 	y6p := persistM6("y6",y6)
 	y6 = y6p.Get()
+	y7p := persistIntArray("y7",[]int{1,2,3})
+	_ = y7p
 
 	z := func(interface{}) {
 		_ = persistFloat("y7",1.0)