chore: import upstream snapshot with attribution

server/analyzer/create_function.go

@@ -0,0 +1,56 @@
+// Copyright 2025 Dolthub, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package analyzer
+
+import (
+	"github.com/dolthub/go-mysql-server/sql"
+	"github.com/dolthub/go-mysql-server/sql/analyzer"
+	"github.com/dolthub/go-mysql-server/sql/plan"
+	"github.com/dolthub/go-mysql-server/sql/planbuilder"
+	"github.com/dolthub/go-mysql-server/sql/transform"
+
+	"github.com/dolthub/doltgresql/server/node"
+)
+
+// ValidateCreateFunction validates that a function can be created as specified. It validates functions defined
+// with SQL language.
+func ValidateCreateFunction(ctx *sql.Context, a *analyzer.Analyzer, n sql.Node, scope *plan.Scope, sel analyzer.RuleSelector, qFlags *sql.QueryFlags) (sql.Node, transform.TreeIdentity, error) {
+	ct, ok := n.(*node.CreateFunction)
+	if !ok {
+		return n, transform.SameTree, nil
+	}
+
+	if len(ct.SqlDef) == 0 {
+		return n, transform.SameTree, nil
+	}
+
+	checkFunctionBodiesVar, err := ctx.GetSessionVariable(ctx, "check_function_bodies")
+	if err != nil {
+		return n, transform.SameTree, err
+	}
+	if checkFunctionBodiesVar.(int8) == 0 {
+		return n, transform.SameTree, nil
+	}
+
+	builder := planbuilder.New(ctx, a.Catalog, nil)
+	for _, parsed := range ct.SqlDefParsedStmts {
+		_, _, err = builder.BindOnly(parsed, ct.SqlDef, nil)
+		if err != nil {
+			return nil, transform.SameTree, err
+		}
+	}
+
+	return n, transform.SameTree, nil
+}