Files
tidb/pkg/expression/context.go
2024-09-19 07:11:03 +00:00

126 lines
3.8 KiB
Go

// Copyright 2023 PingCAP, 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 (
"time"
"github.com/pingcap/tidb/pkg/errctx"
"github.com/pingcap/tidb/pkg/expression/exprctx"
"github.com/pingcap/tidb/pkg/parser/mysql"
"github.com/pingcap/tidb/pkg/types"
contextutil "github.com/pingcap/tidb/pkg/util/context"
"github.com/pingcap/tidb/pkg/util/intest"
)
// ParamValues is used to store the values of params in context
type ParamValues = exprctx.ParamValues
// EvalContext is used to evaluate an expression
type EvalContext = exprctx.EvalContext
// BuildContext is used to build an expression
type BuildContext = exprctx.BuildContext
// AggFuncBuildContext is used to build an aggregation expression
type AggFuncBuildContext = exprctx.ExprContext
// OptionalEvalPropKey is an alias of context.OptionalEvalPropKey
type OptionalEvalPropKey = exprctx.OptionalEvalPropKey
// OptionalEvalPropProvider is an alias of context.OptionalEvalPropProvider
type OptionalEvalPropProvider = exprctx.OptionalEvalPropProvider
// OptionalEvalPropKeySet is an alias of context.OptionalEvalPropKeySet
type OptionalEvalPropKeySet = exprctx.OptionalEvalPropKeySet
// OptionalEvalPropDesc is an alias of context.OptionalEvalPropDesc
type OptionalEvalPropDesc = exprctx.OptionalEvalPropDesc
func sqlMode(ctx EvalContext) mysql.SQLMode {
return ctx.SQLMode()
}
func typeCtx(ctx EvalContext) types.Context {
return ctx.TypeCtx()
}
func errCtx(ctx EvalContext) errctx.Context {
return ctx.ErrCtx()
}
func location(ctx EvalContext) (loc *time.Location) {
return ctx.Location()
}
func warningCount(ctx EvalContext) int {
return ctx.WarningCount()
}
func truncateWarnings(ctx EvalContext, start int) []contextutil.SQLWarn {
return ctx.TruncateWarnings(start)
}
// assertionEvalContext is used to do some assertions.
// It is only used in tests.
type assertionEvalContext struct {
EvalContext
fn builtinFunc
}
func wrapEvalAssert(ctx EvalContext, fn builtinFunc) (ret *assertionEvalContext) {
originalCtx := ctx
if assertCtx, ok := ctx.(*assertionEvalContext); ok {
originalCtx = assertCtx.EvalContext
if assertCtx.fn == fn {
ret = assertCtx
}
}
checkEvalCtx(originalCtx)
if ret == nil {
ret = &assertionEvalContext{EvalContext: originalCtx, fn: fn}
}
return
}
func checkEvalCtx(ctx EvalContext) {
tc := ctx.TypeCtx()
intest.Assert(ctx.Location() == tc.Location(),
"location is not equal, ctxLoc: %s, tcLoc: %s", ctx.Location(), tc.Location())
}
func (ctx *assertionEvalContext) GetOptionalPropProvider(key OptionalEvalPropKey) (OptionalEvalPropProvider, bool) {
var requiredOptionalProps OptionalEvalPropKeySet
if ctx.fn != nil {
requiredOptionalProps = ctx.fn.RequiredOptionalEvalProps()
}
intest.Assert(
requiredOptionalProps.Contains(key),
"optional property '%s' is read in function '%T' but not declared in RequiredOptionalEvalProps",
key, ctx.fn,
)
return ctx.EvalContext.GetOptionalPropProvider(key)
}
// StringerWithCtx is the interface for expressions that can be stringified with context.
type StringerWithCtx interface {
// StringWithCtx returns the string representation of the expression with context.
// NOTE: any implementation of `StringWithCtx` should not panic if the context is nil.
StringWithCtx(ctx ParamValues, redact string) string
}