build(deps): bump github.com/golangci/unconvert to HEAD

.golangci.reference.yml

@@ -2293,6 +2293,14 @@ linters-settings:
     # Default: false
     syslog-priority: true
 
+  unconvert:
+    # Remove conversions that force intermediate rounding.
+    # Default: false
+    fast-math: true
+    # Be more conservative (experimental).
+    # Default: false
+    safe: true
+
   unparam:
     # Inspect exported functions.
     #

go.mod

@@ -45,7 +45,7 @@ require (
 	github.com/golangci/gofmt v0.0.0-20231018234816-f50ced29576e
 	github.com/golangci/misspell v0.4.1
 	github.com/golangci/revgrep v0.5.2
-	github.com/golangci/unconvert v0.0.0-20180507085042-28b1c447d1f4
+	github.com/golangci/unconvert v0.0.0-20240309020433-c5143eacb3ed
 	github.com/gordonklaus/ineffassign v0.1.0
 	github.com/gostaticanalysis/forcetypeassert v0.1.0
 	github.com/gostaticanalysis/nilerr v0.1.1
@@ -151,7 +151,6 @@ require (
 	github.com/gostaticanalysis/comment v1.4.2 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
-	github.com/kisielk/gotool v1.0.0 // indirect
 	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
 	github.com/magiconair/properties v1.8.6 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect

pkg/config/linters_settings.go

@@ -268,6 +268,7 @@ type LintersSettings struct {
 	Testifylint     TestifylintSettings
 	Testpackage     TestpackageSettings
 	Thelper         ThelperSettings
+	Unconvert       UnconvertSettings
 	Unparam         UnparamSettings
 	Unused          UnusedSettings
 	UseStdlibVars   UseStdlibVarsSettings
@@ -882,6 +883,11 @@ type UseStdlibVarsSettings struct {
 	SyslogPriority     bool `mapstructure:"syslog-priority"`
 }
 
+type UnconvertSettings struct {
+	FastMath bool `mapstructure:"fast-math"`
+	Safe     bool `mapstructure:"safe"`
+}
+
 type UnparamSettings struct {
 	CheckExported bool `mapstructure:"check-exported"`
 	Algo          string

pkg/golinters/unconvert.go

@@ -3,25 +3,27 @@ package golinters
 import (
 	"sync"
 
-	unconvertAPI "github.com/golangci/unconvert"
+	"github.com/golangci/unconvert"
 	"golang.org/x/tools/go/analysis"
 
+	"github.com/golangci/golangci-lint/pkg/config"
 	"github.com/golangci/golangci-lint/pkg/golinters/goanalysis"
 	"github.com/golangci/golangci-lint/pkg/lint/linter"
 	"github.com/golangci/golangci-lint/pkg/result"
 )
 
 const unconvertName = "unconvert"
 
-func NewUnconvert() *goanalysis.Linter {
+//nolint:dupl // This is not a duplicate of dogsled.
+func NewUnconvert(settings *config.UnconvertSettings) *goanalysis.Linter {
 	var mu sync.Mutex
 	var resIssues []goanalysis.Issue
 
 	analyzer := &analysis.Analyzer{
 		Name: unconvertName,
 		Doc:  goanalysis.TheOnlyanalyzerDoc,
 		Run: func(pass *analysis.Pass) (any, error) {
-			issues := runUnconvert(pass)
+			issues := runUnconvert(pass, settings)
 
 			if len(issues) == 0 {
 				return nil, nil
@@ -45,18 +47,13 @@ func NewUnconvert() *goanalysis.Linter {
 	}).WithLoadMode(goanalysis.LoadModeTypesInfo)
 }
 
-func runUnconvert(pass *analysis.Pass) []goanalysis.Issue {
-	prog := goanalysis.MakeFakeLoaderProgram(pass)
+func runUnconvert(pass *analysis.Pass, settings *config.UnconvertSettings) []goanalysis.Issue {
+	positions := unconvert.Run(pass, settings.FastMath, settings.Safe)
 
-	positions := unconvertAPI.Run(prog)
-	if len(positions) == 0 {
-		return nil
-	}
-
-	issues := make([]goanalysis.Issue, 0, len(positions))
-	for _, pos := range positions {
+	var issues []goanalysis.Issue
+	for _, position := range positions {
 		issues = append(issues, goanalysis.NewIssue(&result.Issue{
-			Pos:        pos,
+			Pos:        position,
 			Text:       "unnecessary conversion",
 			FromLinter: unconvertName,
 		}, pass))

pkg/lint/lintersdb/builder_linter.go

@@ -633,7 +633,7 @@ func (b LinterBuilder) Build(cfg *config.Config) []*linter.Config {
 			WithPresets(linter.PresetBugs).
 			WithURL(""),
 
-		linter.NewConfig(golinters.NewUnconvert()).
+		linter.NewConfig(golinters.NewUnconvert(&cfg.LintersSettings.Unconvert)).
 			WithSince("v1.0.0").
 			WithLoadForGoAnalysis().
 			WithPresets(linter.PresetStyle).

test/linters_test.go

@@ -88,6 +88,7 @@ func testOneSource(t *testing.T, log *logutils.StderrLog, binPath, sourcePath st
 		"--disable-all",
 		"--out-format=json",
 		"--max-same-issues=100",
+		"--max-issues-per-linter=100",
 	}
 
 	for _, addArg := range []string{"", "-Etypecheck"} {

test/testdata/unconvert.go

@@ -1,10 +1,183 @@
 //golangcitest:args -Eunconvert
 package testdata
 
-import "log"
+import "io"
 
-func Unconvert() {
-	a := 1
-	b := int(a) // want "unnecessary conversion"
-	log.Print(b)
+// Various explicit conversions of untyped constants
+// that cannot be removed.
+func _() {
+	const (
+		_ = byte(0)
+		_ = int((real)(0i))
+		_ = complex64(complex(1, 2))
+		_ = (bool)(true || false)
+
+		PtrSize = 4 << (^uintptr(0) >> 63)
+		c0      = uintptr(PtrSize)
+		c1      = uintptr((8-PtrSize)/4*2860486313 + (PtrSize-4)/4*33054211828000289)
+	)
+
+	i := int64(0)
+	_ = i
+}
+
+// Make sure we distinguish function calls from
+// conversion to function type.
+func _() {
+	type F func(F) int
+	var f F
+
+	_ = F(F(nil)) // want "unnecessary conversion"
+	_ = f(F(nil))
+}
+
+// Make sure we don't remove explicit conversions that
+// prevent fusing floating-point operation.
+func _() {
+	var f1, f2, f3, ftmp float64
+	_ = f1 + float64(f2*f3)
+	ftmp = float64(f2 * f3)
+	_ = f1 + ftmp
+	ftmp = f2 * f3
+	_ = f1 + float64(ftmp)
+
+	var c1, c2, c3, ctmp complex128
+	_ = c1 + complex128(c2*c3)
+	ctmp = complex128(c2 * c3)
+	_ = c1 + ctmp
+	ctmp = c2 * c3
+	_ = c1 + complex128(ctmp)
+}
+
+// Basic contains conversion errors for builtin data types
+func Basic() {
+	var vbool bool
+	var vbyte byte
+	var vcomplex128 complex128
+	var vcomplex64 complex64
+	var verror error
+	var vfloat32 float32
+	var vfloat64 float64
+	var vint int
+	var vint16 int16
+	var vint32 int32
+	var vint64 int64
+	var vint8 int8
+	var vrune rune
+	var vstring string
+	var vuint uint
+	var vuint16 uint16
+	var vuint32 uint32
+	var vuint64 uint64
+	var vuint8 uint8
+	var vuintptr uintptr
+
+	_ = bool(vbool)       // want "unnecessary conversion"
+	_ = byte(vbyte)       // want "unnecessary conversion"
+	_ = error(verror)     // want "unnecessary conversion"
+	_ = int(vint)         // want "unnecessary conversion"
+	_ = int16(vint16)     // want "unnecessary conversion"
+	_ = int32(vint32)     // want "unnecessary conversion"
+	_ = int64(vint64)     // want "unnecessary conversion"
+	_ = int8(vint8)       // want "unnecessary conversion"
+	_ = rune(vrune)       // want "unnecessary conversion"
+	_ = string(vstring)   // want "unnecessary conversion"
+	_ = uint(vuint)       // want "unnecessary conversion"
+	_ = uint16(vuint16)   // want "unnecessary conversion"
+	_ = uint32(vuint32)   // want "unnecessary conversion"
+	_ = uint64(vuint64)   // want "unnecessary conversion"
+	_ = uint8(vuint8)     // want "unnecessary conversion"
+	_ = uintptr(vuintptr) // want "unnecessary conversion"
+
+	_ = float32(vfloat32)
+	_ = float64(vfloat64)
+	_ = complex128(vcomplex128)
+	_ = complex64(vcomplex64)
+
+	// Pointers
+	_ = (*bool)(&vbool)             // want "unnecessary conversion"
+	_ = (*byte)(&vbyte)             // want "unnecessary conversion"
+	_ = (*complex128)(&vcomplex128) // want "unnecessary conversion"
+	_ = (*complex64)(&vcomplex64)   // want "unnecessary conversion"
+	_ = (*error)(&verror)           // want "unnecessary conversion"
+	_ = (*float32)(&vfloat32)       // want "unnecessary conversion"
+	_ = (*float64)(&vfloat64)       // want "unnecessary conversion"
+	_ = (*int)(&vint)               // want "unnecessary conversion"
+	_ = (*int16)(&vint16)           // want "unnecessary conversion"
+	_ = (*int32)(&vint32)           // want "unnecessary conversion"
+	_ = (*int64)(&vint64)           // want "unnecessary conversion"
+	_ = (*int8)(&vint8)             // want "unnecessary conversion"
+	_ = (*rune)(&vrune)             // want "unnecessary conversion"
+	_ = (*string)(&vstring)         // want "unnecessary conversion"
+	_ = (*uint)(&vuint)             // want "unnecessary conversion"
+	_ = (*uint16)(&vuint16)         // want "unnecessary conversion"
+	_ = (*uint32)(&vuint32)         // want "unnecessary conversion"
+	_ = (*uint64)(&vuint64)         // want "unnecessary conversion"
+	_ = (*uint8)(&vuint8)           // want "unnecessary conversion"
+	_ = (*uintptr)(&vuintptr)       // want "unnecessary conversion"
+}
+
+// Counter is an int64
+type Counter int64
+
+// ID is a typed identifier
+type ID string
+
+// Metric is a struct
+type Metric struct {
+	ID      ID
+	Counter Counter
+}
+
+// Custom contains conversion errors for builtin data types
+func Custom() {
+	type Local struct{ id ID }
+
+	var counter Counter
+	var id ID
+	var m Metric
+	var local Local
+	var x struct{ id ID }
+
+	_ = Counter(counter)     // want "unnecessary conversion"
+	_ = ID(id)               // want "unnecessary conversion"
+	_ = Metric(m)            // want "unnecessary conversion"
+	_ = Local(local)         // want "unnecessary conversion"
+	_ = (struct{ id ID })(x) // want "unnecessary conversion"
+
+	// Pointers
+	_ = (*Counter)(&counter)   // want "unnecessary conversion"
+	_ = (*ID)(&id)             // want "unnecessary conversion"
+	_ = (*Metric)(&m)          // want "unnecessary conversion"
+	_ = (*Local)(&local)       // want "unnecessary conversion"
+	_ = (*struct{ id ID })(&x) // want "unnecessary conversion"
+}
+
+// Interfaces contains conversion errors for interfaces
+func Interfaces() {
+	var writer io.Writer
+
+	_ = (io.Writer)(writer)   // want "unnecessary conversion"
+	_ = (*io.Writer)(&writer) // want "unnecessary conversion"
+}
+
+// Constructor is a func type
+type Constructor func() ID
+
+// Funcs contains conversion errors for func types
+func Funcs() {
+	type Local func(ID)
+	type Recursive func(Recursive)
+
+	var ctor Constructor
+	var local Local
+	var recursive Recursive
+
+	_ = Constructor(ctor)    // want "unnecessary conversion"
+	_ = Local(local)         // want "unnecessary conversion"
+	_ = Recursive(recursive) // want "unnecessary conversion"
+
+	_ = (*Constructor)(&ctor)    // want "unnecessary conversion"
+	_ = (*Local)(&local)         // want "unnecessary conversion"
+	_ = (*Recursive)(&recursive) // want "unnecessary conversion"
 }