deadlock on unexpected call with mocked argument implementing fmt.Stringer #116
Description
Actual behavior Deadlock on unexpected call to function where one or more arguments are a generated mock that implements fmt.Stringer.
Expected behavior No deadlock on an unexpected call
To Reproduce Steps to reproduce the behavior
- put the files below into a directory
mockgen -package=deadlock -source=interfaces.go -destination=mocks.go- go test -v .
interfaces.go
package deadlock
import "fmt"
type Outer interface {
Consume(Inner)
}
type Inner interface {
fmt.Stringer
}deadlock_test.go
package deadlock
import (
"testing"
"go.uber.org/mock/gomock"
)
func TestDeadlock(t *testing.T) {
ctrl := gomock.NewController(t)
inner := NewMockInner(ctrl)
outer := NewMockOuter(ctrl)
outer.Consume(inner)
}Additional Information
- gomock mode (reflect or source):
source - gomock version or git ref:
v0.3.0 - golang version:
go version go1.21.3 linux/amd64
Triage Notes for the Maintainers
- The call to
ctrl.T.Fatalfin controller.go:209 is holdingctrl.mu Fatalfwill call theString()method on the mock (also unexpectedly)- this will reach controller.go:200 and deadlock
backtrace
goroutine 18 [sync.Mutex.Lock]:
sync.runtime_SemacquireMutex(0x0?, 0x65?, 0x4be6c0?)
/usr/local/go/src/runtime/sema.go:77 +0x25
sync.(*Mutex).lockSlow(0xc000196400)
/usr/local/go/src/sync/mutex.go:171 +0x15d
sync.(*Mutex).Lock(...)
/usr/local/go/src/sync/mutex.go:90
go.uber.org/mock/gomock.(*Controller).Call.func1(0xc0001963f0, {0x517220?, 0xc000184200}, {0x536f30, 0x6}, {0x0, 0x0, 0x0})
.../go/pkg/mod/go.uber.org/mock@v0.3.0/gomock/controller.go:200 +0xd1
go.uber.org/mock/gomock.(*Controller).Call(0xc0001963f0, {0x517220, 0xc000184200}, {0x536f30, 0x6}, {0x0, 0x0, 0x0})
.../go/pkg/mod/go.uber.org/mock@v0.3.0/gomock/controller.go:225 +0xa7
.../deadlock.(*MockInner).String(0xc000184200)
/home/.../deadlock/mocks.go:78 +0x53
fmt.(*pp).handleMethods(0xc00019a680, 0x184220?)
/usr/local/go/src/fmt/print.go:673 +0x2b2
fmt.(*pp).printValue(0xc00019a680, {0x513ea0?, 0xc000184220?, 0x49e866?}, 0x76, 0x1)
/usr/local/go/src/fmt/print.go:770 +0xca
fmt.(*pp).printValue(0xc00019a680, {0x50dd20?, 0xc0001a8090?, 0x5398db?}, 0x76, 0x0)
/usr/local/go/src/fmt/print.go:912 +0x1605
fmt.(*pp).printArg(0xc00019a680, {0x50dd20?, 0xc0001a8090}, 0x76)
/usr/local/go/src/fmt/print.go:759 +0x6a5
fmt.(*pp).doPrintf(0xc00019a680, {0x540a4e, 0x2e}, {0xc000180140?, 0x5, 0x5})
/usr/local/go/src/fmt/print.go:1077 +0x39e
fmt.Sprintf({0x540a4e, 0x2e}, {0xc000180140, 0x5, 0x5})
/usr/local/go/src/fmt/print.go:239 +0x53
testing.(*common).Fatalf(0xc00019e680, {0x540a4e?, 0x40ac65?}, {0xc000180140?, 0x50efa0?, 0x61ef01?})
/usr/local/go/src/testing/testing.go:1082 +0x3f
go.uber.org/mock/gomock.(*Controller).Call.func1(0xc0001963f0, {0x5172a0?, 0xc000184210}, {0x537171, 0x7}, {0xc000184220, 0x1, 0x1})
.../go/pkg/mod/go.uber.org/mock@v0.3.0/gomock/controller.go:209 +0x356
go.uber.org/mock/gomock.(*Controller).Call(0xc0001963f0, {0x5172a0, 0xc000184210}, {0x537171, 0x7}, {0xc000184220, 0x1, 0x1})
.../go/pkg/mod/go.uber.org/mock@v0.3.0/gomock/controller.go:225 +0xa7
.../deadlock.(*MockOuter).Consume(0xc000184210, {0x5670e0?, 0xc000184200})
/home/.../deadlock/mocks.go:43 +0xab
.../deadlock.TestDeadlock(0x0?)
/home/.../deadlock_test.go:13 +0x129
testing.tRunner(0xc00019e680, 0x542e38)
/usr/local/go/src/testing/testing.go:1595 +0xff
created by testing.(*T).Run in goroutine 1
/usr/local/go/src/testing/testing.go:1648 +0x3ad
FAIL .../deadlock 1.006s
FAIL