std: fix calls to Printf(s) with non-constant s

In all cases the intent was not to interpret s as a format string.
In one case (go/types), this was a latent bug in production.
(These were uncovered by a new check in vet's printf analyzer.)

Updates #60529

Change-Id: I3e17af7e589be9aec1580783a1b1011c52ec494b
Reviewed-on: https://go-review.googlesource.com/c/go/+/587855
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Russ Cox <rsc@golang.org>

src/cmd/compile/internal/types2/builtins.go

@@ -533,7 +533,7 @@ func (check *Checker) builtin(x *operand, call *syntax.CallExpr, id builtinId) (
 	case _Max, _Min:
 		// max(x, ...)
 		// min(x, ...)
-		check.verifyVersionf(call.Fun, go1_21, quote(bin.name))
+		check.verifyVersionf(call.Fun, go1_21, "%s", quote(bin.name))
 
 		op := token.LSS
 		if id == _Max {

src/crypto/rsa/pss_test.go

@@ -160,7 +160,7 @@ func TestPSSGolden(t *testing.T) {
 				t.Error(err)
 			}
 		default:
-			t.Fatalf("unknown marker: " + marker)
+			t.Fatalf("unknown marker: %s", marker)
 		}
 	}
 }

src/database/sql/sql_test.go

@@ -1753,7 +1753,7 @@ func TestIssue6651(t *testing.T) {
 
 	want := "error in rows.Next"
 	rowsCursorNextHook = func(dest []driver.Value) error {
-		return fmt.Errorf(want)
+		return errors.New(want)
 	}
 	defer func() { rowsCursorNextHook = nil }()
 
@@ -1765,7 +1765,7 @@ func TestIssue6651(t *testing.T) {
 
 	want = "error in rows.Close"
 	setRowsCloseHook(func(rows *Rows, err *error) {
-		*err = fmt.Errorf(want)
+		*err = errors.New(want)
 	})
 	defer setRowsCloseHook(nil)
 	err = db.QueryRow("SELECT|people|name|").Scan(&v)

src/encoding/json/encode_test.go

@@ -1168,7 +1168,7 @@ func TestMarshalUncommonFieldNames(t *testing.T) {
 func TestMarshalerError(t *testing.T) {
 	s := "test variable"
 	st := reflect.TypeOf(s)
-	errText := "json: test error"
+	const errText = "json: test error"
 
 	tests := []struct {
 		CaseName

src/go/types/builtins.go

@@ -536,7 +536,7 @@ func (check *Checker) builtin(x *operand, call *ast.CallExpr, id builtinId) (_ b
 	case _Max, _Min:
 		// max(x, ...)
 		// min(x, ...)
-		check.verifyVersionf(call.Fun, go1_21, quote(bin.name))
+		check.verifyVersionf(call.Fun, go1_21, "%s", quote(bin.name))
 
 		op := token.LSS
 		if id == _Max {

src/go/types/typexpr.go

@@ -488,7 +488,7 @@ func (check *Checker) instantiatedType(ix *typeparams.IndexExpr, def *TypeName)
 				if i < len(ix.Indices) {
 					pos = ix.Indices[i].Pos()
 				}
-				check.softErrorf(atPos(pos), InvalidTypeArg, err.Error())
+				check.softErrorf(atPos(pos), InvalidTypeArg, "%v", err)
 			} else {
 				check.mono.recordInstance(check.pkg, ix.Pos(), inst.TypeParams().list(), inst.TypeArgs().list(), ix.Indices)
 			}

src/internal/coverage/cfile/emitdata_test.go

@@ -197,7 +197,7 @@ func testForSpecificFunctions(t *testing.T, dir string, want []string, avoid []s
 		}
 	}
 	if rval != "" {
-		t.Logf("=-= begin output:\n" + output + "\n=-= end output\n")
+		t.Logf("=-= begin output:\n%s\n=-= end output\n", output)
 	}
 	return rval
 }

src/math/big/int_test.go

@@ -1909,7 +1909,7 @@ func TestFillBytes(t *testing.T) {
 		"0xffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff",
 	} {
 		t.Run(n, func(t *testing.T) {
-			t.Logf(n)
+			t.Log(n)
 			x, ok := new(Int).SetString(n, 0)
 			if !ok {
 				panic("invalid test entry")

src/math/rand/rand_test.go

@@ -77,7 +77,7 @@ func checkSampleDistribution(t *testing.T, samples []float64, expected *statsRes
 	actual := getStatsResults(samples)
 	err := actual.checkSimilarDistribution(expected)
 	if err != nil {
-		t.Errorf(err.Error())
+		t.Error(err)
 	}
 }
 

src/math/rand/v2/rand_test.go

@@ -74,7 +74,7 @@ func checkSampleDistribution(t *testing.T, samples []float64, expected *statsRes
 	actual := getStatsResults(samples)
 	err := actual.checkSimilarDistribution(expected)
 	if err != nil {
-		t.Errorf(err.Error())
+		t.Error(err)
 	}
 }
 

src/net/http/serve_test.go

@@ -4743,11 +4743,11 @@ Host: foo
 func TestHandlerFinishSkipBigContentLengthRead(t *testing.T) {
 	setParallel(t)
 	conn := newTestConn()
-	conn.readBuf.Write([]byte(fmt.Sprintf(
+	conn.readBuf.WriteString(
 		"POST / HTTP/1.1\r\n" +
 			"Host: test\r\n" +
 			"Content-Length: 9999999999\r\n" +
-			"\r\n" + strings.Repeat("a", 1<<20))))
+			"\r\n" + strings.Repeat("a", 1<<20))
 
 	ls := &oneConnListener{conn}
 	var inHandlerLen int

src/net/smtp/smtp.go

@@ -206,7 +206,7 @@ func (c *Client) Auth(a Auth) error {
 	}
 	resp64 := make([]byte, encoding.EncodedLen(len(resp)))
 	encoding.Encode(resp64, resp)
-	code, msg64, err := c.cmd(0, strings.TrimSpace(fmt.Sprintf("AUTH %s %s", mech, resp64)))
+	code, msg64, err := c.cmd(0, "%s", strings.TrimSpace(fmt.Sprintf("AUTH %s %s", mech, resp64)))
 	for err == nil {
 		var msg []byte
 		switch code {
@@ -232,7 +232,7 @@ func (c *Client) Auth(a Auth) error {
 		}
 		resp64 = make([]byte, encoding.EncodedLen(len(resp)))
 		encoding.Encode(resp64, resp)
-		code, msg64, err = c.cmd(0, string(resp64))
+		code, msg64, err = c.cmd(0, "%s", resp64)
 	}
 	return err
 }

src/net/smtp/smtp_test.go

@@ -772,10 +772,10 @@ func TestSendMail(t *testing.T) {
 
 		tc := textproto.NewConn(conn)
 		for i := 0; i < len(data) && data[i] != ""; i++ {
-			tc.PrintfLine(data[i])
+			tc.PrintfLine("%s", data[i])
 			for len(data[i]) >= 4 && data[i][3] == '-' {
 				i++
-				tc.PrintfLine(data[i])
+				tc.PrintfLine("%s", data[i])
 			}
 			if data[i] == "221 Goodbye" {
 				return

src/runtime/pprof/pprof_test.go

@@ -1272,7 +1272,7 @@ func TestMutexProfile(t *testing.T) {
 		if ok, err := regexp.MatchString(r3, lines[5]); err != nil || !ok {
 			t.Errorf("%q didn't match %q", lines[5], r3)
 		}
-		t.Logf(prof)
+		t.Log(prof)
 	})
 	t.Run("proto", func(t *testing.T) {
 		// proto format