fixed issue of initializing editor multiple times

[peonone]

It fixes #655, also addresses #640.

The fix is to initialize the editor (byinitMonaco) only when the component is mounted, and dispose the editor only before it's unmounted, as the props updating is already handled by perspective side effects.

[domoritz]

Thank you. Can you fix the lint issues?

[domoritz]

@KostiantynPopovych could you review this before I merge it since you sent #625?

@manooog, you also had some comments on the original pull request. Do you think this is a good change?

[peonone]

@domoritz Could you clarify about the lint issues? I re-ran yarn lint and nothing changed.
Not sure if you meant the warnings like

src/editor.tsx
   82:25  warning  React Hook useEffect has missing dependencies: 'className', 'defaultValue', 'handleEditorDidMount', 'handleEditorWillMount', 'language', 'options', 'overrideServices', 'theme', and 'value'. Either include them or remove the dependency array  react-hooks/exhaustive-deps

These are expected, as we used those properties in the init side effect but don't want to trigger the effect again once any changed.

[domoritz]

I'm not following. If we remove the array, does that change the behavior?

[peonone]

@domoritz Yes (ref),

• removing the array parameter, it will be triggered for every re-rendering, works the same as componentDidUpdate
• by empty array, it will be triggered only once after the component is mounted, same as componentDidMount

[domoritz]

Then let's add a comment that suppressed the warning so we don't accidentally remove the array in the future.

[domoritz]

Thank you. I published 0.51.0 with the fix.