UnhandledPromiseRejectionWarning: Unhandled promise rejection.

**Description:**

Most of the times, when i am working on ionic app, when ever i make few changes in the code, this is the issue i am getting. It is not even allowing me to work continuously for five minutes. It is totally wasting time. I tried with ionic cli 3.x and then switched to 4.x but still the same issue with both the versions.


**Steps to Reproduce:**

**Output:**

**My `ionic info`:**

```
[WARN] You are not in an Ionic project directory. Project context may be missing.
cli packages: (/xxxxxxxxxxx/node/v8.11.2/lib/node_modules)

@ionic/cli-utils : 2.0.0-alpha.0405736c
ionic (Ionic CLI) : 4.0.0-alpha.0405736c

System:

NodeJS : v8.11.2
npm : 6.0.1
OS : macOS High Sierra
```

**Other Information:**

Start by reproducing the warning while editing an Ionic app with the reported Ionic CLI 3.x and 4.x environments, using the listed Node.js, npm, and macOS versions. Capture the complete verbose output and identify the operation that triggers the unhandled rejection; done means the warning no longer interrupts continuous work.

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