NewSubtreeFolder no longer can return an error as it inlines the jsonCodec

Signed-off-by: Owen Diehl <[email protected]>

Author: owen-d

pkg/querier/astmapper/subtree_folder.go

@@ -14,8 +14,8 @@ type subtreeFolder struct{}
 
 // NewSubtreeFolder creates a subtreeFolder which can reduce an AST
 // to one embedded query if it contains no embedded queries yet
-func NewSubtreeFolder() (ASTMapper, error) {
-	return NewASTNodeMapper(&subtreeFolder{}), nil
+func NewSubtreeFolder() ASTMapper {
+	return NewASTNodeMapper(&subtreeFolder{})
 }
 
 // MapNode impls NodeMapper

pkg/querier/astmapper/subtree_folder_test.go

@@ -96,8 +96,7 @@ func TestSubtreeMapper(t *testing.T) {
 		},
 	} {
 		t.Run(fmt.Sprintf("[%d]", i), func(t *testing.T) {
-			mapper, err := NewSubtreeFolder()
-			require.Nil(t, err)
+			mapper := NewSubtreeFolder()
 
 			expr, err := promql.ParseExpr(tc.input)
 			require.Nil(t, err)

pkg/querier/queryrange/querysharding.go

@@ -148,10 +148,7 @@ func (ast *astMapperware) Do(ctx context.Context, r Request) (Response, error) {
 		return nil, err
 	}
 
-	subtreeFolder, err := astmapper.NewSubtreeFolder(astmapper.JSONCodec)
-	if err != nil {
-		return nil, err
-	}
+	subtreeFolder := astmapper.NewSubtreeFolder()
 
 	strQuery := r.GetQuery()
 	mappedQuery, err := mapQuery(