Fix a bug for state list with no resources

tfexec/terraform_state_list.go

@@ -35,5 +35,13 @@ func (c *terraformCLI) StateList(ctx context.Context, state *State, addresses []
 		return nil, err
 	}
 
-	return strings.Split(strings.TrimRight(stdout, "\n"), "\n"), nil
+	// we want to split stdout by '\n', but strings.Split returns []string{""} if stdout is empty.
+	// we should remove empty strings from the list so that its length to be 0.
+	resources := strings.FieldsFunc(
+		strings.TrimRight(stdout, "\n"),
+		func(c rune) bool {
+			return c == '\n'
+		},
+	)
+	return resources, nil
 }

tfexec/terraform_state_list_test.go

@@ -122,6 +122,19 @@ aws_security_group.foo
 			want:      nil,
 			ok:        false,
 		},
+		{
+			desc: "no resources",
+			mockCommands: []*mockCommand{
+				{
+					args:     []string{"terraform", "state", "list"},
+					stdout:   "",
+					exitCode: 0,
+				},
+			},
+			state: nil,
+			want:  []string{},
+			ok:    true,
+		},
 	}
 
 	for _, tc := range cases {