chore: import upstream snapshot with attribution

2026-07-13 12:32:25 +08:00
commit e014feafe1
2285 changed files with 1131979 additions and 0 deletions
@@ -0,0 +1,240 @@
+// 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 expression
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"github.com/cockroachdb/errors"
+	"github.com/dolthub/go-mysql-server/sql"
+	"github.com/dolthub/go-mysql-server/sql/expression"
+	vitess "github.com/dolthub/vitess/go/vt/sqlparser"
+
+	"github.com/dolthub/doltgresql/core"
+	pgtypes "github.com/dolthub/doltgresql/server/types"
+)
+
+// ExplicitCast represents a VALUE::TYPE expression.
+type ExplicitCast struct {
+	sqlChild       sql.Expression
+	castToType     *pgtypes.DoltgresType
+	domainNullable bool
+	domainChecks   sql.CheckConstraints
+}
+
+var _ vitess.Injectable = (*ExplicitCast)(nil)
+var _ sql.Expression = (*ExplicitCast)(nil)
+
+// NewExplicitCastInjectable returns an incomplete *ExplicitCast that must be resolved through the vitess.Injectable interface.
+func NewExplicitCastInjectable(castToType sql.Type) (*ExplicitCast, error) {
+	pgtype, ok := castToType.(*pgtypes.DoltgresType)
+	if !ok {
+		return nil, errors.Errorf("cast expects a Doltgres type as the target type")
+	}
+	return &ExplicitCast{
+		sqlChild:   nil,
+		castToType: pgtype,
+	}, nil
+}
+
+// NewExplicitCast returns a new *ExplicitCast expression.
+func NewExplicitCast(expr sql.Expression, toType *pgtypes.DoltgresType) *ExplicitCast {
+	toType = checkForDomainType(toType)
+	return &ExplicitCast{
+		sqlChild:   expr,
+		castToType: toType,
+	}
+}
+
+// Children implements the sql.Expression interface.
+func (c *ExplicitCast) Children() []sql.Expression {
+	return []sql.Expression{c.sqlChild}
+}
+
+// Child returns the child that is being cast.
+func (c *ExplicitCast) Child() sql.Expression {
+	return c.sqlChild
+}
+
+// Eval implements the sql.Expression interface.
+func (c *ExplicitCast) Eval(ctx *sql.Context, row sql.Row) (any, error) {
+	if !c.castToType.IsResolvedType() {
+		return nil, errors.Errorf("cannot call ExplicitCast.Eval with unresolved cast to type: %s", c.castToType.String())
+	}
+
+	val, err := c.sqlChild.Eval(ctx, row)
+	if err != nil {
+		return nil, err
+	}
+	sourceType, ok := c.sqlChild.Type(ctx).(*pgtypes.DoltgresType)
+	if !ok {
+		// We'll leverage GMSCast to handle the conversion from a GMS type to a Doltgres type.
+		// Rather than re-evaluating the expression, we put the result in a literal.
+		gmsCast := NewGMSCast(expression.NewLiteral(val, c.sqlChild.Type(ctx)))
+		val, err = gmsCast.Eval(ctx, row)
+		if err != nil {
+			return nil, err
+		}
+		sourceType = gmsCast.DoltgresType(ctx)
+	}
+
+	baseCastToType := checkForDomainType(c.castToType)
+	castsColl, err := core.GetCastsCollectionFromContext(ctx, "")
+	if err != nil {
+		return nil, err
+	}
+	cast, err := castsColl.GetExplicitCast(ctx, sourceType, baseCastToType)
+	if err != nil {
+		return nil, err
+	}
+	if !cast.ID.IsValid() {
+		return nil, errors.Errorf(
+			"EXPLICIT CAST: cast from `%s` to `%s` does not exist: %s",
+			sourceType.String(), c.castToType.String(), c.sqlChild.String(),
+		)
+	}
+	if val == nil {
+		if c.castToType.TypType == pgtypes.TypeType_Domain && !c.domainNullable {
+			return nil, pgtypes.ErrDomainDoesNotAllowNullValues.New(c.castToType.Name())
+		}
+		if !cast.Function.IsValid() {
+			return nil, nil
+		}
+	}
+	castResult, err := cast.Eval(ctx, val, sourceType, c.castToType)
+	if err != nil {
+		// For string types and string array types, we intentionally ignore the error as using a length-restricted cast
+		// is a way to intentionally truncate the data. All string types will always return the truncated result, even
+		// during an error, so it's safe to use.
+		castToType := c.castToType
+		if c.castToType.IsArrayType() {
+			castToType = c.castToType.ArrayBaseType()
+		}
+		// A nil result will be returned if there's a critical error, which we should never ignore.
+		if castToType.TypCategory != pgtypes.TypeCategory_StringTypes || castResult == nil {
+			return nil, err
+		}
+	}
+
+	if c.castToType.TypType == pgtypes.TypeType_Domain {
+		for _, check := range c.domainChecks {
+			res, err := sql.EvaluateCondition(ctx, check.Expr, sql.Row{castResult})
+			if err != nil {
+				return nil, err
+			}
+			if sql.IsFalse(res) {
+				return nil, pgtypes.ErrDomainValueViolatesCheckConstraint.New(c.castToType.Name(), check.Name)
+			}
+		}
+	}
+
+	return castResult, nil
+}
+
+// IsNullable implements the sql.Expression interface.
+func (c *ExplicitCast) IsNullable(ctx *sql.Context) bool {
+	// TODO: verify if this is actually nullable
+	return true
+}
+
+// Resolved implements the sql.Expression interface.
+func (c *ExplicitCast) Resolved() bool {
+	if c.sqlChild != nil && c.sqlChild.Resolved() {
+		return true
+	}
+	return false
+}
+
+// String implements the sql.Expression interface.
+func (c *ExplicitCast) String() string {
+	var sqlChild string
+	if c.sqlChild == nil {
+		sqlChild = "unresolved"
+	} else {
+		sqlChild = c.sqlChild.String()
+	}
+	// type needs to be upper-case to match InputExpression in AliasExpr
+	return fmt.Sprintf("%s::%s", sqlChild, strings.ToUpper(c.castToType.String()))
+}
+
+// Type implements the sql.Expression interface.
+func (c *ExplicitCast) Type(ctx *sql.Context) sql.Type {
+	return c.castToType
+}
+
+// WithChildren implements the sql.Expression interface.
+func (c *ExplicitCast) WithChildren(ctx *sql.Context, children ...sql.Expression) (sql.Expression, error) {
+	if len(children) != 1 {
+		return nil, sql.ErrInvalidChildrenNumber.New(c, len(children), 1)
+	}
+	return &ExplicitCast{
+		sqlChild:       children[0],
+		castToType:     c.castToType,
+		domainNullable: c.domainNullable,
+		domainChecks:   c.domainChecks,
+	}, nil
+}
+
+// WithResolvedChildren implements the vitess.InjectableExpression interface.
+func (c *ExplicitCast) WithResolvedChildren(ctx context.Context, children []any) (any, error) {
+	if len(children) != 1 {
+		return nil, errors.Errorf("invalid vitess child count, expected `1` but got `%d`", len(children))
+	}
+	resolvedExpression, ok := children[0].(sql.Expression)
+	if !ok {
+		return nil, errors.Errorf("expected vitess child to be an expression but has type `%T`", children[0])
+	}
+	if !c.castToType.IsResolvedType() {
+		sqlCtx, ok := ctx.(*sql.Context)
+		if !ok {
+			return nil, errors.Errorf("%T requires a SQL context for type resolution", c)
+		}
+		typeColl, err := core.GetTypesCollectionFromContext(sqlCtx, "")
+		if err != nil {
+			return nil, err
+		}
+		resolvedType, err := typeColl.ResolveType(sqlCtx, c.castToType.ID)
+		if err != nil {
+			return nil, err
+		}
+		c.castToType = resolvedType
+	}
+	if !c.castToType.IsDefined {
+		return nil, pgtypes.ErrTypeIsOnlyAShell.New(c.castToType.Name())
+	}
+	return &ExplicitCast{
+		sqlChild:       resolvedExpression,
+		castToType:     c.castToType,
+		domainNullable: c.domainNullable,
+		domainChecks:   c.domainChecks,
+	}, nil
+}
+
+// WithCastToType returns a copy of the expression with castToType replaced.
+func (c *ExplicitCast) WithCastToType(t *pgtypes.DoltgresType) sql.Expression {
+	ec := *c
+	ec.castToType = t
+	return &ec
+}
+
+// WithDomainConstraints returns a copy of the expression with domain constraints defined.
+func (c *ExplicitCast) WithDomainConstraints(nullable bool, checks sql.CheckConstraints) sql.Expression {
+	ec := *c
+	ec.domainNullable = nullable
+	ec.domainChecks = checks
+	return &ec
+}