From 5a615d81787c561803aa5b08ff0764bdb5388048 Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <evgeniy@nspcc.ru>
Date: Wed, 24 Jun 2020 19:25:08 +0300
Subject: [PATCH] compiler: allow to omit types for nested slices

---
 pkg/compiler/codegen.go    | 14 +++++---------
 pkg/compiler/slice_test.go | 21 +++++++++++++++++++++
 2 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/pkg/compiler/codegen.go b/pkg/compiler/codegen.go
index 3df5ffa43..7093acae3 100644
--- a/pkg/compiler/codegen.go
+++ b/pkg/compiler/codegen.go
@@ -594,15 +594,11 @@ func (c *codegen) Visit(node ast.Node) ast.Visitor {
 		return nil
 
 	case *ast.CompositeLit:
-		typ := c.typeOf(n.Type).Underlying()
-		switch n.Type.(type) {
-		case *ast.Ident, *ast.SelectorExpr, *ast.MapType:
-			switch typ.(type) {
-			case *types.Struct:
-				c.convertStruct(n)
-			case *types.Map:
-				c.convertMap(n)
-			}
+		switch typ := c.typeOf(n).Underlying().(type) {
+		case *types.Struct:
+			c.convertStruct(n)
+		case *types.Map:
+			c.convertMap(n)
 		default:
 			ln := len(n.Elts)
 			// ByteArrays needs a different approach than normal arrays.
diff --git a/pkg/compiler/slice_test.go b/pkg/compiler/slice_test.go
index b90283a2a..2dfe9adbc 100644
--- a/pkg/compiler/slice_test.go
+++ b/pkg/compiler/slice_test.go
@@ -222,6 +222,27 @@ var sliceTestCases = []testCase{
 		}`,
 		big.NewInt(42),
 	},
+	{
+		"nested slice omitted type (slice)",
+		`package foo
+		func Main() int {
+			a := [][]int{{1, 2}, {3, 4}}
+			a[1][0] = 42
+			return a[1][0]
+		}`,
+		big.NewInt(42),
+	},
+	{
+		"nested slice omitted type (struct)",
+		`package foo
+		type pair struct { a, b int }
+		func Main() int {
+			a := []pair{{a: 1, b: 2}, {a: 3, b: 4}}
+			a[1].a = 42
+			return a[1].a
+		}`,
+		big.NewInt(42),
+	},
 }
 
 func TestSliceOperations(t *testing.T) {