fix(worker): fix between filter for non indexed predicates

[minhaj-shakeel]

Fixes DGRAPH-2528.
Fixes DGRAPH-2544.

This PR extends the support for between filter on non-indexed predicates so that it could be used outside the root also. For example, for the given schema

type CarModel {
	make
	model
	year
}
model                          : string @index(term) @lang .
make                           : string @index(term) .
year                           : int .

The below query uses between filter on year predicate which is non-indexed, should be valid.

queryCareModel(func: type(CarModel)) @filter(between(year,2009,2010)){
				make
				model
				year
			}

This PR also fixes the eq filter for more than one argument on the non-indexed predicate which earlier used to compare with just the first of the given arguments for eq filter. For eg the below query was not giving proper results earlier.

queryCarModel(func: type(CarModel)) @filter(eq(year,2008,2009)){
				make
				model
				year
			}

---

This change is 

[codelingo]

LGTM. 14 rules errored during the review.

[codelingo]

LGTM. 12 rules errored during the review.

[pawanrawal]

Reviewable status: 0 of 2 files reviewed, 4 unresolved discussions (waiting on @manishrjain, @minhaj-shakeel, @pawanrawal, and @vvbalaji-dgraph)

---

query/query0_test.go, line 3295 at r1 (raw file):

		`
		{
			me(func: type(CarModel)) @filter(between(year,2009,2010)){

Also, add a test where between is used in a filter on a child node.

{

  me(users) {
    car @filter(between(....)) {
      make
       model
    }
  }

}

---

worker/task.go, line 463 at r1 (raw file):

						}
					case "between":
						if types.CompareVals("ge", val, srcFn.eqTokens[0]) &&

Can we add a function for this check and use it both here and at the root?

---

worker/task.go, line 466 at r1 (raw file):

							types.CompareVals("le", val, srcFn.eqTokens[1]) {
							uidList.Uids = append(uidList.Uids, q.UidList.Uids[i])
							break

not needed

---

worker/task.go, line 471 at r1 (raw file):

						if types.CompareVals(srcFn.fname, val, srcFn.eqTokens[0]) {
							uidList.Uids = append(uidList.Uids, q.UidList.Uids[i])
							break

not needed

[minhaj-shakeel]

Reviewable status: 0 of 3 files reviewed, 4 unresolved discussions (waiting on @manishrjain, @pawanrawal, and @vvbalaji-dgraph)

---

query/query0_test.go, line 3295 at r1 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

Also, add a test where between is used in a filter on a child node.

{

  me(users) {
    car @filter(between(....)) {
      make
       model
    }
  }

}

Done.

---

worker/task.go, line 463 at r1 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

Can we add a function for this check and use it both here and at the root?

Done.

---

worker/task.go, line 466 at r1 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

not needed

Done.

---

worker/task.go, line 471 at r1 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

not needed

Done.

[codelingo]

LGTM. 15 rules errored during the review.

[codelingo]

LGTM. 11 rules errored during the review.

[pawanrawal]

Reviewable status: 0 of 3 files reviewed, 3 unresolved discussions (waiting on @manishrjain, @minhaj-shakeel, @pawanrawal, and @vvbalaji-dgraph)

---

query/query0_test.go, line 3295 at r2 (raw file):

			`Test Between on Indexed Predicate`,
			`{
				me(func :has(newname))  @filter(eq(newname,"P1","P3")){

these queries are not using between, did you intend to use between instead of eq.

[minhaj-shakeel]

Reviewable status: 0 of 3 files reviewed, 3 unresolved discussions (waiting on @manishrjain, @pawanrawal, and @vvbalaji-dgraph)

---

query/query0_test.go, line 3295 at r2 (raw file):

Previously, pawanrawal (Pawan Rawal) wrote…

these queries are not using between, did you intend to use between instead of eq.

Sorry for the mistake, I have corrected it.

[codelingo]

LGTM. 5 rules errored during the review.

[pawanrawal]

Reviewed 2 of 3 files at r2, 1 of 1 files at r3.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @manishrjain, @pawanrawal, and @vvbalaji-dgraph)