chore: import upstream snapshot with attribution

server/ast/foreign_key_constraint_table_def.go

@@ -0,0 +1,85 @@
+// Copyright 2023 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 ast
+
+import (
+	"github.com/cockroachdb/errors"
+
+	vitess "github.com/dolthub/vitess/go/vt/sqlparser"
+
+	"github.com/dolthub/doltgresql/postgres/parser/sem/tree"
+)
+
+// nodeForeignKeyConstraintTableDef handles *tree.ForeignKeyConstraintTableDef nodes.
+func nodeForeignKeyConstraintTableDef(ctx *Context, node *tree.ForeignKeyConstraintTableDef, notValid bool) (*vitess.ForeignKeyDefinition, error) {
+	if node == nil {
+		return nil, nil
+	}
+	var matchType vitess.ForeignKeyMatchType
+	switch node.Match {
+	case tree.MatchSimple:
+		matchType = vitess.MatchSimple
+	case tree.MatchFull:
+		matchType = vitess.MatchFull
+	case tree.MatchPartial:
+		return nil, errors.Errorf("MATCH PARTIAL is not yet supported")
+	default:
+		return nil, errors.Errorf("unknown foreign key MATCH strategy")
+	}
+	tableName, err := nodeTableName(ctx, &node.Table)
+	if err != nil {
+		return nil, err
+	}
+	fromCols := make([]vitess.ColIdent, len(node.FromCols))
+	for i := range node.FromCols {
+		fromCols[i] = vitess.NewColIdent(string(node.FromCols[i]))
+	}
+	toCols := make([]vitess.ColIdent, len(node.ToCols))
+	for i := range node.ToCols {
+		toCols[i] = vitess.NewColIdent(string(node.ToCols[i]))
+	}
+	var refActions [2]vitess.ReferenceAction
+	for i, refAction := range []tree.RefAction{node.Actions.Delete, node.Actions.Update} {
+		switch refAction.Action {
+		case tree.NoAction:
+			refActions[i] = vitess.NoAction
+		case tree.Restrict:
+			refActions[i] = vitess.Restrict
+		case tree.SetNull:
+			refActions[i] = vitess.SetNull
+			if refAction.Columns != nil {
+				return nil, errors.Errorf("SET NULL <columns> is not yet supported")
+			}
+		case tree.SetDefault:
+			refActions[i] = vitess.SetDefault
+			if refAction.Columns != nil {
+				return nil, errors.Errorf("SET DEFAULT <columns> is not yet supported")
+			}
+		case tree.Cascade:
+			refActions[i] = vitess.Cascade
+		default:
+			return nil, errors.Errorf("unknown foreign key reference action encountered")
+		}
+	}
+	return &vitess.ForeignKeyDefinition{
+		Source:            fromCols,
+		ReferencedTable:   tableName,
+		ReferencedColumns: toCols,
+		OnDelete:          refActions[0],
+		OnUpdate:          refActions[1],
+		NotValid:          notValid,
+		MatchType:         matchType,
+	}, nil
+}