ember try:ember dies after first failed scenario with 1.0.0-beta.3

[pgengler]

When using ember-try 1.0.0-beta.3, ember try:ember exits immediately after a single scenario fails, without running the remaining scenarios or outputting the summary. (0.2.23 and 1.0.0-beta.1 work as expected.)

I created a new addon as a testcase, with a single failing test in it: https://github.com/pgengler/ember-try-testcase

To reproduce:

1. Clone the test addon and run yarn install.
2. Run ember try:ember. Only the "default" scenario runs, and execution stops with an error message displayed (see output)

To see beta-1 behavior:

1. Check out the beta-1 branch of the test addon and run yarn install.
2. Run ember try:ember. The scenarios all run to completion. (see output)

[rwjblue]

ember try:ember

Do you mean try:each here?

[kategengler]

try:ember is a command too ;) This should also affect try:each.

I haven't confirmed yet, but believe this to be the problem:
https://github.com/ember-cli/ember-try/blob/master/lib/utils/run.js#L20 needs to .catch to handle non-zero exit codes, rather than checking in .then (per https://github.com/sindresorhus/execa#usage)

No tests caught this because they either mock run OR don't test some failures, so we'll need a test for this too.