feat: add UseTesting linter

Author: ldez

.golangci.next.reference.yml

@@ -3493,6 +3493,30 @@ linters-settings:
     # Default: false
     constant-kind: true
 
+  usetesting:
+    # Enable/disable `context.Background()` detections.
+    # Disabled if Go < 1.24.
+    # Default: true
+    context-background: false
+
+    # Enable/disable `context.TODO()` detections.
+    # Disabled if Go < 1.24.
+    # Default: true
+    context-todo: false
+
+    # Enable/disable `os.Chdir()` detections.
+    # Disabled if Go < 1.24.
+    # Default: true
+    os-chdir: false
+
+    # Enable/disable `os.MkdirTemp()` detections.
+    # Default: true
+    os-mkdir-temp: false
+
+    # Enable/disable `os.Setenv()` detections.
+    # Default: false
+    os-setenv: true
+
   unconvert:
     # Remove conversions that force intermediate rounding.
     # Default: false

go.mod

@@ -68,6 +68,7 @@ require (
 	github.com/lasiar/canonicalheader v1.1.2
 	github.com/ldez/gomoddirectives v0.2.4
 	github.com/ldez/tagliatelle v0.5.0
+	github.com/ldez/usetesting v0.1.0
 	github.com/leonklingele/grouper v1.1.2
 	github.com/macabu/inamedparam v0.1.3
 	github.com/maratori/testableexamples v1.0.0

go.sum

@@ -3273,6 +3273,32 @@
             }
           }
         },
+        "usetesting": {
+          "type": "object",
+          "additionalProperties": false,
+          "properties": {
+            "context-background": {
+              "type": "boolean",
+              "default": true
+            },
+            "context-todo": {
+              "type": "boolean",
+              "default": true
+            },
+            "os-chdir": {
+              "type": "boolean",
+              "default": true
+            },
+            "os-mkdir-temp": {
+              "type": "boolean",
+              "default": true
+            },
+            "os-setenv": {
+              "type": "boolean",
+              "default": false
+            }
+          }
+        },
         "unconvert": {
           "type": "object",
           "additionalProperties": false,

jsonschema/golangci.next.jsonschema.json

@@ -179,6 +179,12 @@ var defaultLintersSettings = LintersSettings{
 		HTTPMethod:     true,
 		HTTPStatusCode: true,
 	},
+	UseTesting: UseTestingSettings{
+		ContextBackground: true,
+		ContextTodo:       true,
+		OSChdir:           true,
+		OSMkdirTemp:       true,
+	},
 	Varnamelen: VarnamelenSettings{
 		MaxDistance:   5,
 		MinNameLength: 3,
@@ -278,6 +284,7 @@ type LintersSettings struct {
 	Unparam         UnparamSettings
 	Unused          UnusedSettings
 	UseStdlibVars   UseStdlibVarsSettings
+	UseTesting      UseTestingSettings
 	Varnamelen      VarnamelenSettings
 	Whitespace      WhitespaceSettings
 	Wrapcheck       WrapcheckSettings
@@ -945,6 +952,14 @@ type UseStdlibVarsSettings struct {
 	SyslogPriority     bool `mapstructure:"syslog-priority"` // Deprecated
 }
 
+type UseTestingSettings struct {
+	ContextBackground bool `mapstructure:"context-background"`
+	ContextTodo       bool `mapstructure:"context-todo"`
+	OSChdir           bool `mapstructure:"os-chdir"`
+	OSMkdirTemp       bool `mapstructure:"os-mkdir-temp"`
+	OSSetenv          bool `mapstructure:"os-setenv"`
+}
+
 type UnconvertSettings struct {
 	FastMath bool `mapstructure:"fast-math"`
 	Safe     bool `mapstructure:"safe"`

pkg/config/linters_settings.go

@@ -0,0 +1,15 @@
+//golangcitest:args -Eusetesting
+package testdata
+
+import (
+	"os"
+	"testing"
+)
+
+func Test_osMkdirTemp(t *testing.T) {
+	os.MkdirTemp("", "") // want `os\.MkdirTemp\(\) could be replaced by <t/b/tb>\.TempDir\(\) in .+`
+}
+
+func Test_osSetenv(t *testing.T) {
+	os.Setenv("", "")
+}

pkg/golinters/usetesting/testdata/usetesting.go

@@ -0,0 +1,16 @@
+//golangcitest:args -Eusetesting
+//golangcitest:config_path testdata/usetesting_configuration.yml
+package testdata
+
+import (
+	"os"
+	"testing"
+)
+
+func Test_osMkdirTemp(t *testing.T) {
+	os.MkdirTemp("", "")
+}
+
+func Test_osSetenv(t *testing.T) {
+	os.Setenv("", "") // want `os\.Setenv\(\) could be replaced by <t/b/tb>\.Setenv\(\) in .+`
+}

pkg/golinters/usetesting/testdata/usetesting_configuration.go

@@ -0,0 +1,7 @@
+linters-settings:
+  usetesting:
+    context-background: false
+    context-todo: false
+    os-chdir: false
+    os-mkdir-temp: false
+    os-setenv: true

pkg/golinters/usetesting/testdata/usetesting_configuration.yml

@@ -0,0 +1,30 @@
+//go:build go1.24
+
+//golangcitest:args -Eusetesting
+package testdata
+
+import (
+	"context"
+	"os"
+	"testing"
+)
+
+func Test_contextBackground(t *testing.T) {
+	context.Background() // want `context\.Background\(\) could be replaced by <t/b/tb>\.Context\(\) in .+`
+}
+
+func Test_contextTODO(t *testing.T) {
+	context.TODO() // want `context\.TODO\(\) could be replaced by <t/b/tb>\.Context\(\) in .+`
+}
+
+func Test_osChdir(t *testing.T) {
+	os.Chdir("") // want `os\.Chdir\(\) could be replaced by <t/b/tb>\.Chdir\(\) in .+`
+}
+
+func Test_osMkdirTemp(t *testing.T) {
+	os.MkdirTemp("", "") // want `os\.MkdirTemp\(\) could be replaced by <t/b/tb>\.TempDir\(\) in .+`
+}
+
+func Test_osSetenv(t *testing.T) {
+	os.Setenv("", "")
+}

pkg/golinters/usetesting/testdata/usetesting_go124.go

@@ -0,0 +1,31 @@
+//go:build go1.24
+
+//golangcitest:args -Eusetesting
+//golangcitest:config_path testdata/usetesting_go124_configuration.yml
+package testdata
+
+import (
+	"context"
+	"os"
+	"testing"
+)
+
+func Test_contextBackground(t *testing.T) {
+	context.Background()
+}
+
+func Test_contextTODO(t *testing.T) {
+	context.TODO()
+}
+
+func Test_osChdir(t *testing.T) {
+	os.Chdir("")
+}
+
+func Test_osMkdirTemp(t *testing.T) {
+	os.MkdirTemp("", "")
+}
+
+func Test_osSetenv(t *testing.T) {
+	os.Setenv("", "") // want `os\.Setenv\(\) could be replaced by <t/b/tb>\.Setenv\(\) in .+`
+}