fix #2485 for some types requiring a scalar

[mstephano]

Following PR # 2486, some types require a scalar to work properly. This PR fixes some of them except float32 and uint64. The reasons are as follow:

• float32: the precision changed when marshalling/unmarshalling from float64 back to float32. As an example, value of 5.76 comes out as 5.760000228881836. Anyone knows how to fix this? You can see this branch for an example, or precisely this commit.
• uint64: it is bigger than int64

I have:

• Added tests covering the bug / feature (see testing)
• Updated any relevant documentation (see docs)

[coveralls]

Coverage: 75.54% (-0.04%) from 75.579% when pulling 2c266a3 on mstephano:fix/unusual-basic into 11c3a4d on 99designs:master.

[mstephano]

I named these as Unusual but a suggestion for a better name is welcomed.

[mojtabacazi]

This commit actually broke our app, it generates invalid code when trying to unmarshal typed scalars. It evens breaks time.Duration types to name a few. Here is an example:

func (ec *executionContext) unmarshalNInt642timeᚐDuration(ctx context.Context, v interface{}) (time.Duration, error) {
	res, err := graphql.UnmarshalInt64(v)
	return res, graphql.ErrorOnPath(ctx, err)
}

which causes this error:

cannot use res (variable of type int64) as type time.Duration in return statement

Here is another example with a pointer type

func (ec *executionContext) unmarshalOBoolean2DummyFilter(ctx context.Context, v interface{}) (*dummy.DummyFilter, error) {
	if v == nil {
		return nil, nil
	}
	res, err := graphql.UnmarshalBoolean(v)
	return &res, graphql.ErrorOnPath(ctx, err)
}

[StevenACoffman]

@mojtabacazi Did #2528 fix your issue?

[StevenACoffman]

also related: #2486

[mojtabacazi]

@mojtabacazi Did #2528 fix your issue?

Nope, still an issue in v0.17.26

[StevenACoffman]

@mojtabacazi I reverted this, so please see if v0.17.27 resolves your issue!