kola: `--multiply` on a test with subtests doesn't work

[dustymabe]

When calling kolet the test name gets passed in mangled. I was able to see this with a small patch:

$ git diff mantle/kola/cluster/cluster.go
diff --git a/mantle/kola/cluster/cluster.go b/mantle/kola/cluster/cluster.go
index 24f3bce03..ce1898628 100644
--- a/mantle/kola/cluster/cluster.go
+++ b/mantle/kola/cluster/cluster.go
@@ -75,6 +75,7 @@ func (t *TestCluster) RunLogged(name string, f func(c TestCluster)) bool {
 // RunNative runs a registered NativeFunc on a remote machine
 func (t *TestCluster) RunNative(funcName string, m platform.Machine) bool {
        command := fmt.Sprintf("./kolet run %q %q", t.H.Name(), funcName)
+       t.Logf("command is %s", command)
        return t.Run(funcName, func(c TestCluster) {
                client, err := m.SSHClient()
                if err != nil {

and then running a simple --multiply=2 basic:

kola -p qemu run --multiply=2 basic --output-dir tmp/kola                                                             
⏭️   Skipping kola test pattern "fcos.internet":           
  👉 https://github.com/coreos/coreos-assembler/pull/1478                                                             
  👉 https://github.com/coreos/coreos-assembler/pull/1478                                                             
⏭️   Skipping kola test pattern "podman.workflow":                                                                    
  👉 https://github.com/coreos/coreos-assembler/pull/1478                                                             
🕒  Snoozing kola test pattern "ext.config.kdump.crash" until Sep 16 2024                                             
  👉 https://github.com/coreos/fedora-coreos-tracker/issues/1791                                                      
=== RUN   basic0                                           
=== RUN   basic1                                           
=== RUN   basic0/ReadOnly                                  
=== RUN   basic0/Useradd                                   
=== RUN   basic0/MachineID                                 
=== RUN   basic0/FCOSGrowpart                              
=== RUN   basic0/PortSSH                                   
=== RUN   basic0/DbusPerms                                 
=== RUN   basic0/ServicesActive                            
--- FAIL: basic0 (27.21s)                                  
        cluster.go:78: command is ./kolet run "basic0" "ReadOnly"                                                     
        cluster.go:96: kolet:                              
Usage:                                                     
  kolet run [test] [func] [flags]                          
  kolet run [command]                                      

Available Commands:                                        
  basic 

Note that kolet should have been called with ./kolet run "basic" "ReadOnly" but the multiplied test name got the appended 0, which appears to be breaking things.

[nbspsemicolon]

This seems to arise from harness.go:

coreos-assembler/mantle/kola/harness.go

Line 788 in 701df4a

newName := fmt.Sprintf("%s%d", name, i)

The name is the map key, though, as seen in register.go:

coreos-assembler/mantle/kola/register/register.go

Lines 133 to 142 in 701df4a

	func Register(m map[string]*Test, t *Test) {
	if len(t.Conflicts) > 0 && !t.NonExclusive {
	panic("exclusive test cannot have non-empty conflicts entry")
	}
	_, ok := m[t.Name]
	if ok {
	panic(fmt.Sprintf("test %v already registered", t.Name))
	}
	m[t.Name] = t
	}

I can offer two quick first-round options:

1. Add a field to the Test struct for iteration and use it as a compound key in registering
2. Add a known unique suffix format to the name and strip it in the test run