panic is hidden if there are any failed expectations

[emilien-puget]

this unit test shows the issue, the test without the mock reporter will not show the panic and will instead report a fail expectation.

package simple

import (
	"testing"

	. "github.com/ovechkin-dm/mockio/mock"
	"github.com/ovechkin-dm/mockio/tests/common"
)

type myInterface interface {
	Foo(a int) int
}

func TestSimple_panic_mock_reporter(t *testing.T) {
	r := common.NewMockReporter(t)
	SetUp(r)
	m := Mock[myInterface]()
	WhenSingle(m.Foo(Any[int]())).ThenReturn(42).Verify(Once())
	panic("boom")
	m.Foo(10)
}

func TestSimple_panic(t *testing.T) {
	SetUp(t)
	m := Mock[myInterface]()
	WhenSingle(m.Foo(Any[int]())).ThenReturn(42).Verify(Once())
	panic("boom")
	m.Foo(10)
}

[emilien-puget]

may be linked to #59

[emilien-puget]

func (e *EnrichedReporter) StackTraceErrorf(format string, args ...any) {
	s := NewStackTrace()
	result := fmt.Sprintf(format, args...)
	var st string
	if e.cfg.PrintStackTrace {
		st = fmt.Sprintf(`At:
	%s
Cause:
	%s
Trace:
%s
`, s.CallerLine(), result, s.WithoutLibraryCalls().String())
	} else {
		st = fmt.Sprintf(`At:
	%s
Cause:
	%s
`, s.CallerLine(), result)
	}

	fmt.Println(st)
	// e.reporter.Fatalf(st)
}

changing the last line to a simple print showed me the panic

here is some related issues i found about this topic

golang/go#41355
golang/go@a408139
golang/mock#428

[emilien-puget]

switching to ErrorF instead of FatalF seems to solve the issue but this should have been fixed in the go std lib so i am a but confused

// ErrorReporter is an interface for reporting errors during test execution.
// Implementations of this interface should provide a way to fail the test with a message.
type ErrorReporter interface {
	// Fatalf reports an error and fails the test execution.
	// It formats the message according to a format specifier and arguments
	// It can be used to report an error and provide additional context about the error.
	Fatalf(format string, args ...any)
	Errorf(format string, args ...any)
	// Cleanup adds hooks that are used to clean up data after test was executed.
	Cleanup(func())
}

[ovechkin-dm]

Thanks for pointing that out.
I don’t have the access to my laptop this week. But from what I can see, the solution could be to not invoke cleanup() verification, if the test is failed already.

[ovechkin-dm]

The problem is not that trivial as it turned out.
So as you suggested, I've used Errorf for cleanup and Fatalf for other scenarios, because I still want tests to fail early.
So the output of panicing test will be like this:

=== RUN   TestCleanupShadowsPanic
    reporter.go:67: At:
        	/usr/local/go/src/testing/testing.go:1175 +0x10f
        Cause:
        	expected num method calls: 1, got : 0
        		Foo.Baz(Equal[int], Equal[int], Equal[int])
        
        Trace:
        testing.(*common).Cleanup.func1()
        	/usr/local/go/src/testing/testing.go:1175 +0x10f
        testing.(*common).runCleanup(0xc0001824e0, 0xc000006e00?)
        	/usr/local/go/src/testing/testing.go:1353 +0xdb
        testing.tRunner.func2()
        	/usr/local/go/src/testing/testing.go:1683 +0x25
        panic({0x5f8880?, 0x6937d0?})
        	/usr/local/go/src/runtime/panic.go:770 +0x132
        github.com/ovechkin-dm/mockio/tests/reporting.TestCleanupShadowsPanic(0xc0001824e0?)
        	/home/dovechkin/workspace/mockio/tests/reporting/error_reporting_test.go:203 +0xe6
        testing.tRunner(0xc0001824e0, 0x6506f0)
        	/usr/local/go/src/testing/testing.go:1689 +0xfb
        created by testing.(*T).Run in goroutine 1
        	/usr/local/go/src/testing/testing.go:1742 +0x390
        
--- FAIL: TestCleanupShadowsPanic (0.00s)
panic: failed [recovered]
	panic: failed

goroutine 2 [running]:
testing.tRunner.func1.2({0x5f8880, 0x6937d0})
	/usr/local/go/src/testing/testing.go:1631 +0x24a
testing.tRunner.func1()
	/usr/local/go/src/testing/testing.go:1634 +0x377
panic({0x5f8880?, 0x6937d0?})
	/usr/local/go/src/runtime/panic.go:770 +0x132
github.com/ovechkin-dm/mockio/tests/reporting.TestCleanupShadowsPanic(0xc0001824e0?)
	/home/dovechkin/workspace/mockio/tests/reporting/error_reporting_test.go:203 +0xe6
testing.tRunner(0xc0001824e0, 0x6506f0)
	/usr/local/go/src/testing/testing.go:1689 +0xfb
created by testing.(*T).Run in goroutine 1
	/usr/local/go/src/testing/testing.go:1742 +0x390


Process finished with the exit code 1

Can you please review PR and maybe add some suggestions?

[emilien-puget]

Some tests would be appreciated, as it is quite a weird case

[ovechkin-dm]

Closed the issue, fixed in v0.6.2.