Effects: support assert-like contracts

- Support functions that explicitly express relation between successfull
return and passed arguments (e.g., 'check')
- Note that we have to correct resulting data flow for arguments *after*
resoling (because we get contracts only after resolving). To do so, we
have to extend MutableDataFlowInfoForArguments interface with
'updateResultInfo' method.

==========
Introduction of EffectSystem: 11/18

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/CallCompleter.kt

@@ -22,6 +22,7 @@ import org.jetbrains.kotlin.builtins.getValueParameterTypesFromFunctionType
 import org.jetbrains.kotlin.builtins.isFunctionType
 import org.jetbrains.kotlin.config.LanguageVersionSettings
 import org.jetbrains.kotlin.descriptors.CallableDescriptor
+import org.jetbrains.kotlin.contracts.EffectSystem
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.resolve.*
 import org.jetbrains.kotlin.resolve.BindingContext.CONSTRAINT_SYSTEM_COMPLETER
@@ -47,6 +48,7 @@ import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResultsImpl
 import org.jetbrains.kotlin.resolve.calls.results.ResolutionStatus
 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowInfo
 import org.jetbrains.kotlin.resolve.calls.tasks.TracingStrategy
+import org.jetbrains.kotlin.resolve.scopes.receivers.TransientReceiver
 import org.jetbrains.kotlin.types.ErrorUtils
 import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.types.TypeUtils
@@ -61,7 +63,8 @@ class CallCompleter(
         private val callCheckers: Iterable<CallChecker>,
         private val builtIns: KotlinBuiltIns,
         private val languageVersionSettings: LanguageVersionSettings,
-        private val deprecationResolver: DeprecationResolver
+        private val deprecationResolver: DeprecationResolver,
+        private val effectSystem: EffectSystem
 ) {
     fun <D : CallableDescriptor> completeCall(
             context: BasicCallResolutionContext,
@@ -131,6 +134,7 @@ class CallCompleter(
     ) {
         if (resolvedCall == null || resolvedCall.isCompleted || resolvedCall.constraintSystem == null) {
             completeArguments(context, results)
+            resolvedCall?.updateResultDataFlowInfoUsingEffects(context.trace)
             resolvedCall?.markCallAsCompleted()
             return
         }
@@ -140,6 +144,7 @@ class CallCompleter(
         completeArguments(context, results)
 
         resolvedCall.updateResolutionStatusFromConstraintSystem(context, tracing)
+        resolvedCall.updateResultDataFlowInfoUsingEffects(context.trace)
         resolvedCall.markCallAsCompleted()
     }
 
@@ -393,4 +398,14 @@ class CallCompleter(
         val expressionType = trace.getType(expression.receiverExpression)
         return expressionType != null && TypeUtils.isNullableType(expressionType)
     }
+
+    private fun MutableResolvedCall<*>.updateResultDataFlowInfoUsingEffects(bindingTrace: BindingTrace) {
+        if (dataFlowInfoForArguments is MutableDataFlowInfoForArguments.WithoutArgumentsCheck) return
+
+        val moduleDescriptor = DescriptorUtils.getContainingModule(this.resultingDescriptor?.containingDeclaration ?: return)
+        val resultDFIfromES = effectSystem.getDataFlowInfoForFinishedCall(this, bindingTrace, moduleDescriptor)
+        dataFlowInfoForArguments.updateResultInfo(resultDFIfromES)
+
+        effectSystem.recordDefiniteInvocations(this, bindingTrace, moduleDescriptor)
+    }
 }

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/model/DataFlowInfoForArgumentsImpl.java

@@ -82,4 +82,12 @@ public class DataFlowInfoForArgumentsImpl extends MutableDataFlowInfoForArgument
         if (resultInfo == null) return initialDataFlowInfo;
         return initialDataFlowInfo.and(resultInfo);
     }
+
+    @Override
+    public void updateResultInfo(@NotNull DataFlowInfo dataFlowInfo) {
+        if (dataFlowInfo.equals(DataFlowInfo.Companion.getEMPTY())) return;
+
+        if (resultInfo == null) resultInfo = initialDataFlowInfo;
+        resultInfo = resultInfo.and(dataFlowInfo);
+    }
 }

compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/model/MutableDataFlowInfoForArguments.java

@@ -29,6 +29,7 @@ public abstract class MutableDataFlowInfoForArguments implements DataFlowInfoFor
     }
 
     public abstract void updateInfo(@NotNull ValueArgument valueArgument, @NotNull DataFlowInfo dataFlowInfo);
+    public abstract void updateResultInfo(@NotNull DataFlowInfo dataFlowInfo);
 
     @NotNull
     @Override
@@ -47,6 +48,11 @@ public abstract class MutableDataFlowInfoForArguments implements DataFlowInfoFor
             throw new IllegalStateException();
         }
 
+        @Override
+        public void updateResultInfo(@NotNull DataFlowInfo dataFlowInfo) {
+            throw new IllegalStateException();
+        }
+
         @NotNull
         @Override
         public DataFlowInfo getInfo(@NotNull ValueArgument valueArgument) {

compiler/frontend/src/org/jetbrains/kotlin/types/expressions/ControlStructureTypingUtils.java

@@ -206,6 +206,9 @@ public class ControlStructureTypingUtils {
             dataFlowInfoForArgumentsMap.put(valueArgument, dataFlowInfo);
         }
 
+        @Override
+        public void updateResultInfo(@NotNull DataFlowInfo dataFlowInfo) { }
+
         @NotNull
         @Override
         public DataFlowInfo getInfo(@NotNull ValueArgument valueArgument) {