wehub-resource-sync
51 lines
1.5 KiB
Go
51 lines
1.5 KiB
Go
// Copyright 2024 Dolthub, Inc.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package functions
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import (
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"github.com/dolthub/go-mysql-server/sql"
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"github.com/dolthub/doltgresql/server/functions/framework"
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pgtypes "github.com/dolthub/doltgresql/server/types"
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)
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// initLeft registers the functions to the catalog.
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func initLeft() {
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framework.RegisterFunction(left_text_int32)
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}
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// left_text_int32 represents the PostgreSQL function of the same name, taking the same parameters.
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var left_text_int32 = framework.Function2{
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Name: "left",
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Return: pgtypes.Text,
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Parameters: [2]*pgtypes.DoltgresType{pgtypes.Text, pgtypes.Int32},
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Strict: true,
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Callable: func(ctx *sql.Context, _ [3]*pgtypes.DoltgresType, strInt any, nInt any) (any, error) {
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str := strInt.(string)
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n := nInt.(int32)
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if n >= 0 {
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if int(n) > len(str) {
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return str, nil
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}
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return str[:n], nil
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} else {
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if len(str)+int(n) <= 0 {
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return "", nil
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}
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return str[:len(str)+int(n)], nil
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}
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},
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}
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