Use type when available to resolve expand predicates.

[martinmr]

When a node has a dgraph.type edge, expandSubgraph will use the type
definition to determine the list of predicates to expand instead of
_predicate_.

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This change is 

[codexnull]

Reviewed 3 of 3 files at r1.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @martinmr)

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query/common_test.go, line 506 at r1 (raw file):

		<200> <automaker> "Ford" .
		<200> <make> "Focus" .

This is not important but I think most people would refer to "Ford" as the "make" and "Focus" as the "model".

[martinmr]

Reviewable status: 1 of 3 files reviewed, 1 unresolved discussion (waiting on @codexnull)

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query/common_test.go, line 506 at r1 (raw file):

Previously, codexnull (Javier Alvarado) wrote…

This is not important but I think most people would refer to "Ford" as the "make" and "Focus" as the "model".

Done.

[codexnull]

Reviewed 3 of 3 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved

[gitlw]

Reviewable status: complete! all files reviewed, all discussions resolved

[manishrjain]

Bunch of comments. Get final approval from @gitlw

Reviewed 3 of 3 files at r2.
Reviewable status: all files reviewed, 7 unresolved discussions (waiting on @martinmr)

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query/query.go, line 1934 at r2 (raw file):

			span.Annotate(nil, "expand(_reverse_)")
			if len(types) > 0 {
				typePreds := getNodePredicatesFromTypes(types)

preds := getPredicatesFromTypes(types)

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query/query.go, line 1936 at r2 (raw file):

				typePreds := getNodePredicatesFromTypes(types)

				rpreds, err := getReversePredicatesFromType(ctx, typePreds)

rpreds, err := getReversePredicates(ctx, preds)

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query/query.go, line 2533 at r2 (raw file):

	return result.ValueMatrix, nil
}

Add a TODO.

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query/query.go, line 2565 at r2 (raw file):

	return uniqueValues(result.ValueMatrix), nil
}

Add comments.

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query/query.go, line 2572 at r2 (raw file):

		typeDef, ok := schema.State().GetType(typeName)
		if !ok {
			return preds

continue?

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query/query.go, line 2582 at r2 (raw file):

}

func getReversePredicatesFromType(ctx context.Context, typePreds []string) ([]string, error) {

preds

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query/query.go, line 2589 at r2 (raw file):

	}

	schs, err := worker.GetSchemaOverNetwork(ctx, &pb.SchemaRequest{})

Maybe can be more specific about which predicates you want to get the schema for.

[martinmr]

Reviewable status: all files reviewed, 7 unresolved discussions (waiting on @manishrjain)

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query/query.go, line 1934 at r2 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

preds := getPredicatesFromTypes(types)

Done.

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query/query.go, line 1936 at r2 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

rpreds, err := getReversePredicates(ctx, preds)

function name is already being used. I'll rename it in the next PR to minimize merge conflicts with the PR I already started.

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query/query.go, line 2533 at r2 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

Add a TODO.

I already started the next PR and removed this function so I'll skip this to minimize merge conflicts.

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query/query.go, line 2565 at r2 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

Add comments.

Done.

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query/query.go, line 2572 at r2 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

continue?

Done.

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query/query.go, line 2582 at r2 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

preds

Done.

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query/query.go, line 2589 at r2 (raw file):

Previously, manishrjain (Manish R Jain) wrote…

Maybe can be more specific about which predicates you want to get the schema for.

Done.

[gitlw]

Reviewable status: 1 of 3 files reviewed, 7 unresolved discussions (waiting on @codexnull and @manishrjain)

[gitlw]

Reviewable status: 1 of 3 files reviewed, 7 unresolved discussions (waiting on @codexnull and @manishrjain)