Added txtar test

gno.land/cmd/gnoland/testdata/append.txtar

@@ -0,0 +1,77 @@
+# start a new node
+gnoland start
+
+gnokey maketx addpkg -pkgdir $WORK -pkgpath gno.land/r/append -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1
+
+# Call Append 1
+gnokey maketx call -pkgpath gno.land/r/append -func Append -gas-fee 1000000ugnot -gas-wanted 2000000 -args '1' -broadcast -chainid=tendermint_test test1
+# Call Append 2
+gnokey maketx call -pkgpath gno.land/r/append -func Append -gas-fee 1000000ugnot -gas-wanted 2000000 -args '2' -broadcast -chainid=tendermint_test test1
+# Call Append 3
+gnokey maketx call -pkgpath gno.land/r/append -func Append -gas-fee 1000000ugnot -gas-wanted 2000000 -args '3' -broadcast -chainid=tendermint_test test1
+
+# Call render
+gnokey maketx call -pkgpath gno.land/r/append -func Render -gas-fee 1000000ugnot -gas-wanted 2000000 -args '' -broadcast -chainid=tendermint_test test1
+
+cmp stdout stdout.golden.1
+
+# Call Pop
+gnokey maketx call -pkgpath gno.land/r/append -func Pop -gas-fee 1000000ugnot -gas-wanted 2000000 -broadcast -chainid=tendermint_test test1
+# Call render
+gnokey maketx call -pkgpath gno.land/r/append -func Render -gas-fee 1000000ugnot -gas-wanted 2000000 -args '' -broadcast -chainid=tendermint_test test1
+
+cmp stdout stdout.golden.2
+
+# Call Append 42
+gnokey maketx call -pkgpath gno.land/r/append -func Append -gas-fee 1000000ugnot -gas-wanted 2000000 -args '42' -broadcast -chainid=tendermint_test test1
+
+# Call render
+gnokey maketx call -pkgpath gno.land/r/append -func Render -gas-fee 1000000ugnot -gas-wanted 2000000 -args '' -broadcast -chainid=tendermint_test test1
+
+cmp stdout stdout.golden.3
+
+-- append.gno --
+package append
+
+import (
+	"gno.land/p/demo/ufmt"
+)
+
+type T struct{ i int }
+
+var a []T
+
+func init() {
+	a = make([]T, 0, 1)
+}
+
+func Pop() {
+	a = append(a[:0], a[1:]...)
+}
+
+func Append(i int) {
+	a = append(a, T{i: i})
+}
+
+func Render(path string) string {
+	var s string
+	for i:=0;i<len(a);i++{
+		s+=ufmt.Sprintf("%d-", a[i].i)
+	}
+	return s
+}
+-- stdout.golden.1 --
+("1-2-3-" string)
+OK!
+GAS WANTED: 2000000
+GAS USED:   95179
+-- stdout.golden.2 --
+("2-3-" string)
+OK!
+GAS WANTED: 2000000
+GAS USED:   93546
+-- stdout.golden.3 --
+("2-3-42-" string)
+OK!
+GAS WANTED: 2000000
+GAS USED:   95191