feat: add fatcontext linter (#4583)

.golangci.next.reference.yml

@@ -2534,6 +2534,7 @@ linters:
  - exhaustive
  - exhaustruct
  - exportloopref
+ - fatcontext
  - forbidigo
  - forcetypeassert
  - funlen
@@ -2647,6 +2648,7 @@ linters:
  - exhaustive
  - exhaustruct
  - exportloopref
+ - fatcontext
  - forbidigo
  - forcetypeassert
  - funlen

go.mod

@@ -11,6 +11,7 @@ require (
  github.com/Antonboom/nilnil v0.1.7
  github.com/Antonboom/testifylint v1.2.0
  github.com/BurntSushi/toml v1.3.2
+ github.com/Crocmagnon/fatcontext v0.2.2
  github.com/Djarvur/go-err113 v0.0.0-20210108212216-aea10b59be24
  github.com/GaijinEntertainment/go-exhaustruct/v3 v3.2.0
  github.com/OpenPeeDeeP/depguard/v2 v2.2.0

jsonschema/golangci.next.jsonschema.json

@@ -235,6 +235,7 @@
  "exhaustivestruct",
  "exhaustruct",
  "exportloopref",
+ "fatcontext",
  "forbidigo",
  "forcetypeassert",
  "funlen",

pkg/golinters/fatcontext.go

@@ -0,0 +1,19 @@
+package golinters
+
+import (
+ "github.com/Crocmagnon/fatcontext/pkg/analyzer"
+ "golang.org/x/tools/go/analysis"
+
+ "github.com/golangci/golangci-lint/pkg/goanalysis"
+)
+
+func NewFatContext() *goanalysis.Linter {
+ a := analyzer.Analyzer
+
+ return goanalysis.NewLinter(
+ a.Name,
+ a.Doc,
+ []*analysis.Analyzer{a},
+ nil,
+ ).WithLoadMode(goanalysis.LoadModeTypesInfo)
+}

pkg/lint/lintersdb/builder_linter.go

@@ -181,6 +181,12 @@ func (LinterBuilder) Build(cfg *config.Config) ([]*linter.Config, error) {
  WithPresets(linter.PresetStyle).
  WithURL("https://github.com/gostaticanalysis/forcetypeassert"),
 
+ linter.NewConfig(golinters.NewFatContext()).
+ WithSince("1.58.0").
+ WithPresets(linter.PresetPerformance).
+ WithLoadForGoAnalysis().
+ WithURL("https://github.com/Crocmagnon/fatcontext"),
+
  linter.NewConfig(golinters.NewFunlen(&cfg.LintersSettings.Funlen)).
  WithSince("v1.18.0").
  WithPresets(linter.PresetComplexity).

test/testdata/fatcontext.go

@@ -0,0 +1,33 @@
+//golangcitest:args -Efatcontext
+package testdata
+
+import "context"
+
+func example() {
+ ctx := context.Background()
+
+ for i := 0; i < 10; i++ {
+ ctx := context.WithValue(ctx, "key", i)
+ ctx = context.WithValue(ctx, "other", "val")
+ }
+
+ for i := 0; i < 10; i++ {
+ ctx = context.WithValue(ctx, "key", i) // want "nested context in loop"
+ ctx = context.WithValue(ctx, "other", "val")
+ }
+
+ for item := range []string{"one", "two", "three"} {
+ ctx = wrapContext(ctx) // want "nested context in loop"
+ ctx := context.WithValue(ctx, "key", item)
+ ctx = wrapContext(ctx)
+ }
+
+ for {
+ ctx = wrapContext(ctx) // want "nested context in loop"
+ break
+ }
+}
+
+func wrapContext(ctx context.Context) context.Context {
+ return context.WithoutCancel(ctx)
+}