chore: import upstream snapshot with attribution

server/settings/current_schemas.go

@@ -0,0 +1,56 @@
+// Copyright 2024 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 settings
+
+import (
+	"strings"
+
+	"github.com/dolthub/go-mysql-server/sql"
+)
+
+// GetCurrentSchemas returns all the schemas in the search_path setting, with elements like "$user" excluded
+func GetCurrentSchemas(ctx *sql.Context) ([]string, error) {
+	searchPathVar, err := ctx.GetSessionVariable(ctx, "search_path")
+	if err != nil {
+		return nil, err
+	}
+
+	pathElems := strings.Split(searchPathVar.(string), ",")
+	var path []string
+
+	for _, schemaName := range pathElems {
+		schemaName = strings.Trim(schemaName, " ")
+		if schemaName == "\"$user\"" {
+			continue
+		}
+		path = append(path, schemaName)
+	}
+
+	return path, nil
+}
+
+// GetCurrentSchemasAsMap returns the schemas from the search_path setting as a map for easy lookup. Any
+// elements like "$user" are excluded.
+func GetCurrentSchemasAsMap(ctx *sql.Context) (map[string]struct{}, error) {
+	schemas, err := GetCurrentSchemas(ctx)
+	if err != nil {
+		return nil, err
+	}
+	schemaMap := make(map[string]struct{}, len(schemas))
+	for _, schema := range schemas {
+		schemaMap[schema] = struct{}{}
+	}
+	return schemaMap, nil
+}

server/settings/doc.go

@@ -0,0 +1,19 @@
+// Copyright 2024 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 settings provides utility functions for working with settings, such as the search_path setting.
+//
+// This package is intended to be a leaf in the package dependency graph, and should not add dependencies to
+// other Doltgres packages.
+package settings