Evaluate simple math as CQL Expressions

[vitorpamplona]

Is your feature request related to a problem? Please describe.

The following test case demonstrates the use of an ADD operation inside a CQL expression. This test must pass.

import ca.uhn.fhir.context.FhirContext
import ca.uhn.fhir.context.FhirVersionEnum
import com.google.common.truth.Truth.assertThat
import org.hl7.fhir.r4.model.IntegerType
import org.hl7.fhir.r4.model.Parameters
import org.junit.Test
import org.opencds.cqf.cql.engine.fhir.converter.FhirTypeConverterFactory
import org.opencds.cqf.cql.evaluator.builder.CqlEvaluatorBuilder
import org.opencds.cqf.cql.evaluator.builder.EndpointConverter
import org.opencds.cqf.cql.evaluator.builder.data.DataProviderFactory
import org.opencds.cqf.cql.evaluator.builder.data.FhirModelResolverFactory
import org.opencds.cqf.cql.evaluator.builder.data.TypedRetrieveProviderFactory
import org.opencds.cqf.cql.evaluator.builder.library.LibraryContentProviderFactory
import org.opencds.cqf.cql.evaluator.builder.library.TypedLibraryContentProviderFactory
import org.opencds.cqf.cql.evaluator.builder.terminology.TerminologyProviderFactory
import org.opencds.cqf.cql.evaluator.builder.terminology.TypedTerminologyProviderFactory
import org.opencds.cqf.cql.evaluator.cql2elm.util.LibraryVersionSelector
import org.opencds.cqf.cql.evaluator.expression.ExpressionEvaluator
import org.opencds.cqf.cql.evaluator.fhir.adapter.r4.AdapterFactory
import org.opencds.cqf.cql.evaluator.library.CqlFhirParametersConverter

class ExpressionEvaluatorTest {
  @Test
  fun testSimpleMathExpression() {
    val fhirContext = FhirContext.forCached(FhirVersionEnum.R4)
    val adapterFactory = AdapterFactory()

    // Creates a Expression Evaluator without any loaders
    var evaluator = ExpressionEvaluator(
      fhirContext,
      CqlFhirParametersConverter(
        fhirContext, adapterFactory,
        FhirTypeConverterFactory().create(fhirContext.getVersion().getVersion())
      ),
      LibraryContentProviderFactory(
        fhirContext, adapterFactory,
        emptySet<TypedLibraryContentProviderFactory>(),
        LibraryVersionSelector(adapterFactory)
      ),
      DataProviderFactory(
        fhirContext, emptySet<FhirModelResolverFactory>(), emptySet<TypedRetrieveProviderFactory>()
      ),
      TerminologyProviderFactory(
        fhirContext, emptySet<TypedTerminologyProviderFactory>()
      ),
      EndpointConverter(adapterFactory),
      FhirModelResolverFactory()
    ) { CqlEvaluatorBuilder() }

    val params = evaluator.evaluate("1 + 3",null,null,null,null,null,null,null,null,null) as Parameters
    val result = (params.getParameter("return") as IntegerType).value

    assertThat(result).isEqualTo(4);
  }
}

Describe the solution you'd like
The expression 1+3 should be assembled into a CQL library, compiled to ELM and evaluated with the CQL Evaluator.

Describe alternatives you've considered

Additional context
Depends on Issue #1365, and PRs #1326 and #1395, as well as:

• FasterXML's 525
• CQL's 746, PR CQL's 748
• CQL's 640, PR CQL's 745

Would you like to work on the issue?
Yes

[vitorpamplona]

Fixed on #1603