*: enable unconvert (#35821)

ref #35345

DEPS.bzl

@@ -942,6 +942,13 @@ def go_deps():
         sum = "h1:leSNB7iYzLYSSx3J/s5sVf4Drkc68W2wm4Ixh/mr0us=",
         version = "v0.0.0-20180630174525-215b22d4de21",
     )
+    go_repository(
+        name = "com_github_golangci_unconvert",
+        build_file_proto_mode = "disable",
+        importpath = "github.com/golangci/unconvert",
+        sum = "h1:zwtduBRr5SSWhqsYNgcuWO2kFlpdOZbP0+yRjmvPGys=",
+        version = "v0.0.0-20180507085042-28b1c447d1f4",
+    )
 
     go_repository(
         name = "com_github_gomodule_redigo",

br/pkg/lightning/mydump/BUILD.bazel

@@ -31,7 +31,6 @@ go_library(
         "//util/slice",
         "//util/table-filter",
         "@com_github_pingcap_errors//:errors",
-        "@com_github_pingcap_failpoint//:failpoint",
         "@com_github_xitongsys_parquet_go//parquet",
         "@com_github_xitongsys_parquet_go//reader",
         "@com_github_xitongsys_parquet_go//source",

build/BUILD.bazel

@@ -110,5 +110,6 @@ nogo(
         "//build/linter/gofmt:gofmt",
         "//build/linter/ineffassign:ineffassign",
         "//build/linter/prealloc:prealloc",
+        "//build/linter/unconvert:unconvert",
     ] + staticcheck_analyzers(STATICHECK_ANALYZERS),
 )

build/linter/unconvert/BUILD.bazel

@@ -0,0 +1,14 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "unconvert",
+    srcs = ["analysis.go"],
+    importpath = "github.com/pingcap/tidb/build/linter/unconvert",
+    visibility = ["//visibility:public"],
+    deps = [
+        "//build/linter/util",
+        "@com_github_golangci_unconvert//:unconvert",
+        "@org_golang_x_tools//go/analysis",
+        "@org_golang_x_tools//go/loader",
+    ],
+)

build/linter/unconvert/analysis.go

@@ -0,0 +1,61 @@
+// Copyright 2022 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 unconvert
+
+import (
+	"fmt"
+	"go/token"
+	"go/types"
+
+	unconvertAPI "github.com/golangci/unconvert"
+	"github.com/pingcap/tidb/build/linter/util"
+	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/loader"
+)
+
+// Name is the name of the analyzer.
+const Name = "unconvert"
+
+// Analyzer is the analyzer struct of unconvert.
+var Analyzer = &analysis.Analyzer{
+	Name: Name,
+	Doc:  "Remove unnecessary type conversions",
+	Run:  run,
+}
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	var createdPkgs []*loader.PackageInfo
+	createdPkgs = append(createdPkgs, util.MakeFakeLoaderPackageInfo(pass))
+	allPkgs := map[*types.Package]*loader.PackageInfo{}
+	for _, pkg := range createdPkgs {
+		pkg := pkg
+		allPkgs[pkg.Pkg] = pkg
+	}
+	prog := &loader.Program{
+		Fset:        pass.Fset,
+		Imported:    nil,         // not used without .Created in any linter
+		Created:     createdPkgs, // all initial packages
+		AllPackages: allPkgs,     // all initial packages and their depndencies
+	}
+	positions := unconvertAPI.Run(prog)
+	if len(positions) == 0 {
+		return nil, nil
+	}
+
+	for _, pos := range positions {
+		pass.Reportf(token.Pos(pos.Offset), fmt.Sprintf("[%s] Unnecessary conversion", Name))
+	}
+	return nil, nil
+}

build/linter/util/BUILD.bazel

@@ -8,5 +8,6 @@ go_library(
     deps = [
         "@co_honnef_go_tools//analysis/report",
         "@org_golang_x_tools//go/analysis",
+        "@org_golang_x_tools//go/loader",
     ],
 )

build/linter/util/util.go

@@ -22,6 +22,7 @@ import (
 	"strings"
 
 	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/loader"
 	"honnef.co/go/tools/analysis/report"
 )
 
@@ -147,3 +148,22 @@ func FormatCode(code string) string {
 
 	return fmt.Sprintf("`%s`", code)
 }
+
+// MakeFakeLoaderPackageInfo creates a fake loader.PackageInfo for a given package.
+func MakeFakeLoaderPackageInfo(pass *analysis.Pass) *loader.PackageInfo {
+	var errs []error
+
+	typeInfo := pass.TypesInfo
+
+	return &loader.PackageInfo{
+		Pkg:                   pass.Pkg,
+		Importable:            true, // not used
+		TransitivelyErrorFree: true, // not used
+
+		// use compiled (preprocessed) go files AST;
+		// AST linters use not preprocessed go files AST
+		Files:  pass.Files,
+		Errors: errs,
+		Info:   *typeInfo,
+	}
+}

build/nogo_config.json

@@ -210,6 +210,15 @@
       ".*_generated\\.go$": "ignore generated code"
     }
   },
+  "unconvert": {
+    "exclude_files": {
+      "/external/": "no need to vet third party code",
+      ".*\\.pb\\.go$": "generated code",
+      "parser/parser.go": "generated code",
+      "/cgo/": "no need to vet third party code for cgo",
+      ".*_generated\\.go$": "ignore generated code"
+    }
+  },
   "unmarshal": {
     "exclude_files": {
       "/external/": "no need to vet third party code",

executor/seqtest/BUILD.bazel

@@ -17,6 +17,7 @@ go_test(
         "//kv",
         "//meta/autoid",
         "//metrics",
+        "//parser/ast",
         "//parser/model",
         "//parser/mysql",
         "//parser/terror",

go.mod

@@ -99,11 +99,14 @@ require (
 	github.com/aliyun/alibaba-cloud-sdk-go v1.61.1581
 	github.com/charithe/durationcheck v0.0.9
 	github.com/golangci/gofmt v0.0.0-20190930125516-244bba706f1a
+	github.com/golangci/unconvert v0.0.0-20180507085042-28b1c447d1f4
 	github.com/gordonklaus/ineffassign v0.0.0-20210914165742-4cc7213b9bc8
 	github.com/kyoh86/exportloopref v0.1.8
 	honnef.co/go/tools v0.0.1-2020.1.4
 )
 
+require github.com/kisielk/gotool v1.0.0 // indirect
+
 require (
 	cloud.google.com/go v0.100.2 // indirect
 	cloud.google.com/go/compute v1.2.0 // indirect

go.sum

@@ -347,6 +347,8 @@ github.com/golangci/gofmt v0.0.0-20190930125516-244bba706f1a h1:iR3fYXUjHCR97qWS
 github.com/golangci/gofmt v0.0.0-20190930125516-244bba706f1a/go.mod h1:9qCChq59u/eW8im404Q2WWTrnBUQKjpNYKMbU4M7EFU=
 github.com/golangci/prealloc v0.0.0-20180630174525-215b22d4de21 h1:leSNB7iYzLYSSx3J/s5sVf4Drkc68W2wm4Ixh/mr0us=
 github.com/golangci/prealloc v0.0.0-20180630174525-215b22d4de21/go.mod h1:tf5+bzsHdTM0bsB7+8mt0GUMvjCgwLpTapNZHU8AajI=
+github.com/golangci/unconvert v0.0.0-20180507085042-28b1c447d1f4 h1:zwtduBRr5SSWhqsYNgcuWO2kFlpdOZbP0+yRjmvPGys=
+github.com/golangci/unconvert v0.0.0-20180507085042-28b1c447d1f4/go.mod h1:Izgrg8RkN3rCIMLGE9CyYmU9pY2Jer6DgANEnZ/L/cQ=
 github.com/gomodule/redigo v1.7.1-0.20190724094224-574c33c3df38/go.mod h1:B4C85qUVwatsJoIUNIfCRsp7qO0iAmpGFZ4EELWSbC4=
 github.com/google/btree v0.0.0-20180813153112-4030bb1f1f0c/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
 github.com/google/btree v1.0.0/go.mod h1:lNA+9X1NB3Zf8V7Ke586lFgjr2dZNuvo3lPJSGZ5JPQ=
@@ -511,6 +513,7 @@ github.com/kataras/pio v0.0.0-20190103105442-ea782b38602d/go.mod h1:NV88laa9UiiD
 github.com/kisielk/errcheck v1.1.0/go.mod h1:EZBBE59ingxPouuu3KfxchcWSUPOHkagtvWXihfKN4Q=
 github.com/kisielk/errcheck v1.2.0/go.mod h1:/BMXB+zMLi60iA8Vv6Ksmxu/1UDYcXs4uQLJ+jE2L00=
 github.com/kisielk/errcheck v1.5.0/go.mod h1:pFxgyoBC7bSaBwPgfKdkLd5X25qrDl4LWUI2bnpBCr8=
+github.com/kisielk/gotool v1.0.0 h1:AV2c/EiW3KqPNT9ZKl07ehoAGi4C5/01Cfbblndcapg=
 github.com/kisielk/gotool v1.0.0/go.mod h1:XhKaO+MFFWcvkIS/tQcRk01m1F5IRFswLeQ+oQHNcck=
 github.com/klauspost/compress v1.8.2/go.mod h1:RyIbtBH6LamlWaDj8nUwkbUhJ87Yi3uG0guNDohfE1A=
 github.com/klauspost/compress v1.9.0/go.mod h1:RyIbtBH6LamlWaDj8nUwkbUhJ87Yi3uG0guNDohfE1A=

sessiontxn/isolation/BUILD.bazel

@@ -48,10 +48,12 @@ go_test(
         "//parser",
         "//parser/ast",
         "//planner",
+        "//session",
         "//sessionctx",
         "//sessiontxn",
         "//testkit",
         "//testkit/testsetup",
+        "//types",
         "@com_github_pingcap_errors//:errors",
         "@com_github_pingcap_failpoint//:failpoint",
         "@com_github_pingcap_kvproto//pkg/kvrpcpb",

testkit/testfork/BUILD.bazel

@@ -15,4 +15,5 @@ go_test(
     name = "testfork_test",
     srcs = ["fork_test.go"],
     embed = [":testfork"],
+    deps = ["@com_github_stretchr_testify//require"],
 )