cmd/cue: fix panic when importing empty files as a list

Empty files are represented as nil when parsed, which causes cue to panic as the condition is not considered when asked to import as a list. Fixes #2721 Change-Id: I20f3b49eb66661f156c06e036579ce6beddfe0d8 Signed-off-by: Thomas Way <[email protected]> Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1173072 Unity-Result: CUE porcuepine <[email protected]> TryBot-Result: CUEcueckoo <[email protected]> Reviewed-by: Daniel Martí <[email protected]>
cue-lang · Dec 4, 2023 · b36b477 · b36b477
1 parent e1ceed4
commit b36b477
Show file tree

Hide file tree

Showing 2 changed files with 11 additions and 1 deletion.
diff --git a/cmd/cue/cmd/orphans.go b/cmd/cue/cmd/orphans.go
@@ -295,8 +295,10 @@ func placeOrphans(b *buildPlan, d *encoding.Decoder, pkg string, objs ...*ast.Fi
 			f.Decls = append(f.Decls, x.Elts...)
 		case *ast.ListLit:
 			f.Decls = append(f.Decls, &ast.EmbedDecl{Expr: x})
+		case nil:
+			f.Decls = append(f.Decls, ast.NewList())
 		default:
-			panic("unreachable")
+			panic(fmt.Sprintf("unexpected type %T", x))
 		}
 	}
 

diff --git a/cmd/cue/cmd/testdata/script/import_list.txtar b/cmd/cue/cmd/testdata/script/import_list.txtar
@@ -8,6 +8,10 @@ cmp stdout expect-stdout2
 # Issue #369
 exec cue import --with-context -l '"\(path.Ext(filename))": data' ./import3/data.json
 cmpenv import3/data.cue expect3
+
+# Issue #2721
+exec cue import -f --list issue2721/empty.yaml
+cmp issue2721/empty.cue issue2721/empty.cue.golden
 -- expect-stdout1 --
 service: [{
 	kind: "Service"
@@ -50,3 +54,7 @@ deployment: [{
 -- import3/data.json --
 [1]
 -- cue.mod --
+
+-- issue2721/empty.yaml --
+-- issue2721/empty.cue.golden --
+[]