roachtest: add regex to list operations

pkg/cmd/roachtest/main.go

@@ -236,7 +236,7 @@ Check --parallelism, --run-forever and --wait-before-next-execution flags`,
 	rootCmd.AddCommand(runOperationCmd)
 
 	var listOperationCmd = &cobra.Command{
-		Use:   "list-operations",
+		Use:   "list-operations [regex...]",
 		Short: "list all operation names",
 		Long: `List all available operations that can be run with the run-operation command.
 
@@ -245,12 +245,13 @@ This command lists the names of all registered operations.
 Example:
 
    roachtest list-operations
+   roachtest list-operations node-kill/.*m$
 `,
 		RunE: func(cmd *cobra.Command, args []string) error {
 			r := makeTestRegistry()
 			operations.RegisterOperations(&r)
 
-			ops := r.AllOperations()
+			ops := r.FilteredOperations(registry.MergeRegEx(args))
 			for _, op := range ops {
 				fmt.Printf("%s\n", op.Name)
 			}
@@ -459,12 +460,7 @@ func opsToRun(r testRegistryImpl, filter string) ([]registry.OperationSpec, erro
 	if err != nil {
 		return nil, err
 	}
-	var filteredOps []registry.OperationSpec
-	for _, opSpec := range r.AllOperations() {
-		if regex.MatchString(opSpec.Name) {
-			filteredOps = append(filteredOps, opSpec)
-		}
-	}
+	filteredOps := r.FilteredOperations(regex)
 	if len(filteredOps) == 0 {
 		return nil, errors.New("no matching operations to run")
 	}

pkg/cmd/roachtest/registry/filter.go

@@ -57,22 +57,8 @@ func OnlyBenchmarks() TestFilterOption {
 // NewTestFilter initializes a new filter. The strings are interpreted as
 // regular expressions (which are joined with |).
 func NewTestFilter(regexps []string, options ...TestFilterOption) (*TestFilter, error) {
-	makeRE := func(strs []string) *regexp.Regexp {
-		switch len(strs) {
-		case 0:
-			return regexp.MustCompile(`.`)
-		case 1:
-			return regexp.MustCompile(strs[0])
-		default:
-			for i := range strs {
-				strs[i] = "(" + strs[i] + ")"
-			}
-			return regexp.MustCompile(strings.Join(strs, "|"))
-		}
-	}
-
 	tf := &TestFilter{
-		Name: makeRE(regexps),
+		Name: MergeRegEx(regexps),
 	}
 	for _, o := range options {
 		o(tf)
@@ -89,6 +75,21 @@ func NewTestFilter(regexps []string, options ...TestFilterOption) (*TestFilter,
 	return tf, nil
 }
 
+// MergeRegEx merges the given strings into a single regexp.
+func MergeRegEx(strs []string) *regexp.Regexp {
+	switch len(strs) {
+	case 0:
+		return regexp.MustCompile(`.`)
+	case 1:
+		return regexp.MustCompile(strs[0])
+	default:
+		for i := range strs {
+			strs[i] = "(" + strs[i] + ")"
+		}
+		return regexp.MustCompile(strings.Join(strs, "|"))
+	}
+}
+
 // MatchFailReason describes the reason(s) a filter did not match the test.
 type MatchFailReason struct {
 	// If true, the filter requires a benchmark and the test is not one.

pkg/cmd/roachtest/test_registry.go

@@ -180,3 +180,14 @@ func (r testRegistryImpl) AllOperations() []registry.OperationSpec {
 	})
 	return ops
 }
+
+// FilteredOperations returns operations filtered by the given regex.
+func (r testRegistryImpl) FilteredOperations(regex *regexp.Regexp) []registry.OperationSpec {
+	var filteredOps []registry.OperationSpec
+	for _, opSpec := range r.AllOperations() {
+		if regex.MatchString(opSpec.Name) {
+			filteredOps = append(filteredOps, opSpec)
+		}
+	}
+	return filteredOps
+}