From 1d7b6c3c2003faa283346cb92535f15301a62795 Mon Sep 17 00:00:00 2001
From: Kamil Samigullin <kamil@samigullin.info>
Date: Thu, 15 Apr 2021 14:17:14 +0300
Subject: [PATCH] fix #1404: integrate looppointer

---
 go.mod                        |  1 +
 go.sum                        |  5 +++++
 pkg/golinters/looppointer.go  | 21 +++++++++++++++++++++
 pkg/lint/lintersdb/manager.go |  4 ++++
 test/testdata/looppointer.go  | 34 ++++++++++++++++++++++++++++++++++
 5 files changed, 65 insertions(+)
 create mode 100644 pkg/golinters/looppointer.go
 create mode 100644 test/testdata/looppointer.go

diff --git a/go.mod b/go.mod
index e4df46a8b36a..4f922d58b7b6 100644
--- a/go.mod
+++ b/go.mod
@@ -42,6 +42,7 @@ require (
 	github.com/kulti/thelper v0.4.0
 	github.com/kunwardeep/paralleltest v1.0.2
 	github.com/kyoh86/exportloopref v0.1.8
+	github.com/kyoh86/looppointer v0.1.7
 	github.com/ldez/gomoddirectives v0.2.1
 	github.com/ldez/tagliatelle v0.2.0
 	github.com/maratori/testpackage v1.0.1
diff --git a/go.sum b/go.sum
index da58aed60eda..23586e1185e5 100644
--- a/go.sum
+++ b/go.sum
@@ -378,6 +378,10 @@ github.com/kunwardeep/paralleltest v1.0.2/go.mod h1:ZPqNm1fVHPllh5LPVujzbVz1JN2G
 github.com/kylelemons/godebug v1.1.0/go.mod h1:9/0rRGxNHcop5bhtWyNeEfOS8JIWk580+fNqagV/RAw=
 github.com/kyoh86/exportloopref v0.1.8 h1:5Ry/at+eFdkX9Vsdw3qU4YkvGtzuVfzT4X7S77LoN/M=
 github.com/kyoh86/exportloopref v0.1.8/go.mod h1:1tUcJeiioIs7VWe5gcOObrux3lb66+sBqGZrRkMwPgg=
+github.com/kyoh86/looppointer v0.1.7 h1:q5sZOhFvmvQ6ZoZxvPB/Mjj2croWX7L49BBuI4XQWCM=
+github.com/kyoh86/looppointer v0.1.7/go.mod h1:l0cRF49N6xDPx8IuBGC/imZo8Yn1BBLJY0vzI+4fepc=
+github.com/kyoh86/nolint v0.0.0-20200711045849-7a7b0d649b7a h1:WKwgzTn8xp2JuhOUsTbi+h+QygLZSfVGwaYZUejGMMw=
+github.com/kyoh86/nolint v0.0.0-20200711045849-7a7b0d649b7a/go.mod h1:hPeUNhNOZ22wXzQKMzeYKXVFTBjJ9czxjeIDyI1ueVM=
 github.com/ldez/gomoddirectives v0.2.1 h1:9pAcW9KRZW7HQjFwbozNvFMcNVwdCBufU7os5QUwLIY=
 github.com/ldez/gomoddirectives v0.2.1/go.mod h1:sGicqkRgBOg//JfpXwkB9Hj0X5RyJ7mlACM5B9f6Me4=
 github.com/ldez/tagliatelle v0.2.0 h1:693V8Bf1NdShJ8eu/s84QySA0J2VWBanVBa2WwXD/Wk=
@@ -904,6 +908,7 @@ golang.org/x/tools v0.0.0-20200625211823-6506e20df31f/go.mod h1:EkVYQZoAsY45+roY
 golang.org/x/tools v0.0.0-20200626171337-aa94e735be7f/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20200630154851-b2d8b0336632/go.mod h1:EkVYQZoAsY45+roYkvgYkIh4xh/qjgUK9TdY2XT94GE=
 golang.org/x/tools v0.0.0-20200706234117-b22de6825cf7/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
+golang.org/x/tools v0.0.0-20200710042808-f1c4188a97a1/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
 golang.org/x/tools v0.0.0-20200724022722-7017fd6b1305/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
 golang.org/x/tools v0.0.0-20200804011535-6c149bb5ef0d/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
 golang.org/x/tools v0.0.0-20200812195022-5ae4c3c160a0/go.mod h1:njjCfa9FT2d7l9Bc6FUM5FLjQPp3cFF28FI3qnDFljA=
diff --git a/pkg/golinters/looppointer.go b/pkg/golinters/looppointer.go
new file mode 100644
index 000000000000..b52326d9f335
--- /dev/null
+++ b/pkg/golinters/looppointer.go
@@ -0,0 +1,21 @@
+package golinters
+
+import (
+	"github.com/kyoh86/looppointer"
+	"golang.org/x/tools/go/analysis"
+
+	"github.com/golangci/golangci-lint/pkg/golinters/goanalysis"
+)
+
+// NewLoopPointer returns a new instance of Linter based on
+// github.com/kyoh86/looppointer.
+func NewLoopPointer() *goanalysis.Linter {
+	analyzer := looppointer.Analyzer
+
+	return goanalysis.NewLinter(
+		analyzer.Name,
+		analyzer.Doc,
+		[]*analysis.Analyzer{analyzer},
+		nil,
+	).WithLoadMode(goanalysis.LoadModeTypesInfo)
+}
diff --git a/pkg/lint/lintersdb/manager.go b/pkg/lint/lintersdb/manager.go
index 0b8eda617d1b..373c80e9b08c 100644
--- a/pkg/lint/lintersdb/manager.go
+++ b/pkg/lint/lintersdb/manager.go
@@ -488,6 +488,10 @@ func (m Manager) GetAllSupportedLinterConfigs() []*linter.Config {
 			WithSince("v1.40.0").
 			WithPresets(linter.PresetStyle).
 			WithURL("https://github.com/ldez/tagliatelle"),
+		linter.NewConfig(golinters.NewLoopPointer()).
+			WithSince("v1.40.0").
+			WithPresets(linter.PresetBugs).
+			WithURL("https://github.com/kyoh86/looppointer"),
 
 		// nolintlint must be last because it looks at the results of all the previous linters for unused nolint directives
 		linter.NewConfig(golinters.NewNoLintLint()).
diff --git a/test/testdata/looppointer.go b/test/testdata/looppointer.go
new file mode 100644
index 000000000000..d7cb5de86471
--- /dev/null
+++ b/test/testdata/looppointer.go
@@ -0,0 +1,34 @@
+//args: -Elooppointer
+package testdata
+
+func lintLoopPointer() {
+	type domain struct {
+		property *int
+	}
+
+	type dto struct {
+		prop int
+		cond bool
+	}
+
+	result := make([]domain, 0, 3)
+	for _, d := range []dto{
+		{prop: 10},
+		{prop: 11},
+		{prop: 12},
+	} {
+		p := domain{}
+		if !d.cond {
+			p.property = &d.prop // ERROR "taking a pointer for the loop variable d"
+		}
+		result = append(result, p)
+	}
+
+	for _, r := range result {
+		if r.property != nil {
+			// expected 10, 11, 12
+			// obtained 12, 12, 12
+			println(*r.property)
+		}
+	}
+}