[cbarbian-sap]

CAVEAT: THIS PR contains an incompatible change

In general, when merging JSON/YAML objects, component-operator-runtime does not use any special logic for null values.

That is, for example, merging

a:
  b: 1
  c: 2

and

a:
  b: null
  c: 3
  d: 4
  e: null

would result in

a:
  b: null
  c: 3
  d: 4
  e: null

However, helm uses a slightly different approach, in order to allow 'unsetting' default values (to really delete keys, instead of just nullifying them). To be precise: When

• merging user-specified values over the chart's default values or
• merging parent chart default values over a sub chart's default values

helm deletes keys which exist in the underlying values and are null-valued in the incoming values. It is worth to note that an incoming null value is preserved if the key does not exist in the underlying values.

In the above example, the helm logic would return:

a:
  c: 3
  d: 4
  e: null

Note that

• b: is gone (because it exists in the underlying data, and was provided with null value in the incoming data)
• e: is there (because it didn't exist in the underlying data).

This PR makes the HelmGenerator mimic the original helm behaviour. Which could mean an incompatible change in rare cases.