Inconsistency in Ensure*(...) functions

[Kafkalasch]

Hi,

I stumbled across some inconsistencies for the various Ensure*(...) methods.

E.g.

func (d databaseAnalyzer) EnsureAnalyzer(ctx context.Context, analyzer *AnalyzerDefinition) (bool, Analyzer, error) {
	...
	switch code := resp.Code(); code {
	case http.StatusCreated, http.StatusOK:
		return code == http.StatusOK, newAnalyzer(d.db, response.AnalyzerDefinition), nil
	default:
		return false, nil, response.AsArangoErrorWithCode(code)
	}
}

will return true if the analyzer already existed.

func (c *collectionIndexes) EnsurePersistentIndex(ctx context.Context, fields []string, options *CreatePersistentIndexOptions) (IndexResponse, bool, error) {
       ....
	exist, err := c.ensureIndex(ctx, &reqData, &result)
	return newIndexResponse(&result), exist, err
}

func (c *collectionIndexes) ensureIndex(ctx context.Context, reqData interface{}, result interface{}) (bool, error) {
	
	switch code := resp.Code(); code {
	case http.StatusOK:
		return false, nil
	case http.StatusCreated:
		return true, nil
	default:
		return false, response.AsArangoErrorWithCode(code)
	}
}

will return true if the index was created. So it is the other way around.

This is especially misleading, as the variable in the code is called "exist", which is true if it was created and false if it already existed.

I did not check the other, similar methods.

Also: The return order is mixed up. Introducing some consistency here, would make it easier to use the library without the need of digging into the implementation each time something unexpected happens.