New Check: Discourage Usage of ResourceData.Partial() / ResourceData.SetPartial()

[bflad]

Description

The (helper/schema.ResourceData).Partial() and (helper/schema.ResourceData).SetPartial() functionality represents the following:

Partial turns partial state mode on/off.

When partial state mode is enabled, then only key prefixes specified by SetPartial will be in the final state. This allows providers to return partial states for partially applied resources (when errors occur).

SetPartial adds the key to the final state output while in partial state mode. The key must be a root key in the schema (i.e. it cannot be "list.0").

If partial state mode is disabled, then this has no effect. Additionally, whenever partial state mode is toggled, the partial data is cleared.

In practice however, this functionality is of very limited usage as most errors will stop a dependency chain. Partial state writes would also represent the configuration passthrough values and not the API refreshed values usually calculated via re-reading after update. Also as noted above, the usage of d.SetPartial() without d.Partial() is extraneous.

This feels like it may be two checks:

• New Check: Discourage usage of d.Partial()
• New Check: Discourage usage of d.SetPartial()

Flagged Code

d.Partial(true)

d.SetPartial("example")

Passing Code

// Neither used :)

References

• Deprecate (helper/schema.ResourceData).Partial and (helper/schema.ResourceData).SetPartial hashicorp/terraform-plugin-sdk#312