hivesim: add --sim.limit.exact hive flag

hive.go

@@ -26,6 +26,7 @@ func main() {
 		dockerOutput          = flag.Bool("docker.output", false, "Relay all docker output to stderr.")
 		simPattern            = flag.String("sim", "", "Regular `expression` selecting the simulators to run.")
 		simTestPattern        = flag.String("sim.limit", "", "Regular `expression` selecting tests/suites (interpreted by simulators).")
+		simTestExact          = flag.String("sim.limit.exact", "", "Exact `expression` match for tests/suites (interpreted by simulators).")
 		simParallelism        = flag.Int("sim.parallelism", 1, "Max `number` of parallel clients/containers (interpreted by simulators).")
 		simTestLimit          = flag.Int("sim.testlimit", 0, "[DEPRECATED] Max `number` of tests to execute per client (interpreted by simulators).")
 		simTimeLimit          = flag.Duration("sim.timelimit", 0, "Simulation `timeout`. Hive aborts the simulator if it exceeds this time.")
@@ -72,6 +73,9 @@ func main() {
 		log15.Warn("--sim is ignored when using --dev mode")
 		simList = nil
 	}
+	if *simTestExact != "" && *simTestPattern != "" {
+		fatal("only one of --sim.limit and --sim.limit.exact can be provided")
+	}
 
 	// Create the docker backends.
 	dockerConfig := &libdocker.Config{
@@ -108,6 +112,7 @@ func main() {
 	env := libhive.SimEnv{
 		LogDir:             *testResultsRoot,
 		SimLogLevel:        *simLogLevel,
+		SimTestExact:       *simTestExact,
 		SimTestPattern:     *simTestPattern,
 		SimParallelism:     *simParallelism,
 		SimDurationLimit:   *simTimeLimit,

hivesim/hive.go

@@ -35,6 +35,13 @@ func New() *Simulation {
 		panic("HIVE_SIMULATOR environment variable is empty")
 	}
 	sim := &Simulation{url: url}
+	if e := os.Getenv("HIVE_TEST_EXACT"); e != "" {
+		m, err := parseTestExact(e)
+		if err != nil {
+			fmt.Fprintln(os.Stderr, "Warning: invalid exact simulator/test match: "+err.Error())
+		}
+		sim.m = m
+	}
 	if p := os.Getenv("HIVE_TEST_PATTERN"); p != "" {
 		m, err := parseTestPattern(p)
 		if err != nil {

hivesim/testapi.go

@@ -53,6 +53,9 @@ func RunSuite(host *Simulation, suite Suite) error {
 		fmt.Fprintf(os.Stderr, "skipping suite %q because it doesn't match test pattern %s\n", suite.Name, host.m.pattern)
 		return nil
 	}
+	if host.m.isExact && host.m.exactSuite != suite.Name {
+		return nil
+	}
 
 	suiteID, err := host.StartSuite(suite.Name, suite.Description, "")
 	if err != nil {
@@ -82,13 +85,12 @@ func MustRunSuite(host *Simulation, suite Suite) {
 // Using this test type doesn't launch any clients by default. To interact with clients,
 // you can launch them using the t.Client method:
 //
-//    c := t.Client()
-//    c.RPC().Call(...)
+//	c := t.Client()
+//	c.RPC().Call(...)
 //
 // or run a subtest using t.RunClientTest():
 //
-//    t.RunClientTest(hivesim.ClientTestSpec{...})
-//
+//	t.RunClientTest(hivesim.ClientTestSpec{...})
 type TestSpec struct {
 	// These fields are displayed in the UI. Be sure to add
 	// a meaningful description here.
@@ -309,6 +311,9 @@ func runTest(host *Simulation, test testSpec, runit func(t *T)) error {
 		fmt.Fprintf(os.Stderr, "skipping test %q because it doesn't match test pattern %s\n", test.name, host.m.pattern)
 		return nil
 	}
+	if !test.alwaysRun && host.m.isExact && host.m.exactTest != test.name {
+		return nil
+	}
 
 	// Register test on simulation server and initialize the T.
 	t := &T{

hivesim/testmatch.go

@@ -6,9 +6,24 @@ import (
 )
 
 type testMatcher struct {
-	suite   *regexp.Regexp
-	test    *regexp.Regexp
-	pattern string
+	suite      *regexp.Regexp
+	test       *regexp.Regexp
+	pattern    string
+	exactSuite string
+	exactTest  string
+	isExact    bool
+}
+
+func parseTestExact(e string) (m testMatcher, err error) {
+	parts := strings.Split(e, "/")
+	if len(parts) > 0 {
+		m.exactSuite = parts[0]
+	}
+	if len(parts) > 1 {
+		m.exactTest = parts[1]
+	}
+	m.isExact = true
+	return m, nil
 }
 
 func parseTestPattern(p string) (m testMatcher, err error) {

internal/libhive/run.go

@@ -205,6 +205,7 @@ func (r *Runner) run(ctx context.Context, sim string, env SimEnv) (SimResult, er
 			"HIVE_PARALLELISM":  strconv.Itoa(env.SimParallelism),
 			"HIVE_LOGLEVEL":     strconv.Itoa(env.SimLogLevel),
 			"HIVE_TEST_PATTERN": env.SimTestPattern,
+			"HIVE_TEST_EXACT":   env.SimTestExact,
 		},
 	}
 	containerID, err := r.container.CreateContainer(ctx, r.simImages[sim], opts)

internal/libhive/testmanager.go

@@ -35,6 +35,7 @@ type SimEnv struct {
 	SimLogLevel    int
 	SimParallelism int
 	SimTestPattern string
+	SimTestExact   string
 
 	// This is the time limit for the simulation run.
 	// There is no default limit.