From 0cbc32d4a03402130fb07bb23bbc68373bd28d5f Mon Sep 17 00:00:00 2001
From: Grigorii Kirgizov <grigorii.kirgizov@jetbrains.com>
Date: Mon, 20 May 2019 19:00:34 +0300
Subject: [PATCH] Get rid off nullability of Justs

---
 .../src/jetbrains/mps/logic/reactor/core/Occurrence.kt | 10 +++++-----
 .../mps/logic/reactor/core/internal/ControllerImpl.kt  |  2 +-
 .../logic/reactor/core/internal/StoreAwareJournal.kt   |  6 ++----
 .../logic/reactor/evaluation/ConstraintOccurrence.java |  4 ++--
 4 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt b/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt
index c8222332..1e060e46 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/core/Occurrence.kt
@@ -39,7 +39,7 @@ data class Occurrence (val controller: Controller,
                        val constraint: Constraint,
                        val logicalContext: LogicalContext,
                        val arguments: List<*>,
-                       val justifications: Justs?):
+                       val justifications: Justs):
     ConstraintOccurrence,
     LogicalObserver
 {
@@ -58,7 +58,7 @@ data class Occurrence (val controller: Controller,
 
     override fun logicalContext(): LogicalContext = logicalContext
 
-    override fun justifications(): Justs? = justifications
+    override fun justifications(): Justs = justifications
 
     override fun valueUpdated(logical: Logical<*>) {
         if (alive) {
@@ -96,18 +96,18 @@ data class Occurrence (val controller: Controller,
 
 fun Constraint.occurrence(controller: Controller,
                           arguments: List<*>,
-                          justifications: Justs?,
+                          justifications: Justs,
                           logicalContext: LogicalContext): Occurrence =
     Occurrence(controller, this, logicalContext, arguments, justifications)
 
 fun Constraint.occurrence(controller: Controller,
                           arguments: List<*>,
-                          justifications: Justs?): Occurrence =
+                          justifications: Justs): Occurrence =
     Occurrence(controller, this, noLogicalContext, arguments, justifications)
 
 fun Constraint.occurrence(controller: Controller,
                           arguments: List<*>): Occurrence =
-    Occurrence(controller, this, noLogicalContext, arguments, null)
+    Occurrence(controller, this, noLogicalContext, arguments, justsOf())
 
 private val noLogicalContext: LogicalContext = object: LogicalContext {
     override fun <V : Any> variable(metaLogical: MetaLogical<V>): Logical<V>? = null
diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
index 6d1455f5..3bd3a000 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/ControllerImpl.kt
@@ -191,7 +191,7 @@ internal class ControllerImpl (
         val args = supervisor.instantiateArguments(constraint.arguments(), context.logicalContext, context)
         return context.eval { status ->
 
-            state.processActivated(constraint.occurrence(this, args, null, context.logicalContext), status)
+            state.processActivated(constraint.occurrence(this, args, justsOf(), context.logicalContext), status)
 
         }
     }
diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/StoreAwareJournal.kt b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/StoreAwareJournal.kt
index f1c03e37..5aa7c30c 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/StoreAwareJournal.kt
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/core/internal/StoreAwareJournal.kt
@@ -120,7 +120,6 @@ internal open class MatchJournalImpl(view: MatchJournal.View?): MatchJournal {
 
         // Log discards
         match.forEachReplaced {occ ->
-            //            this.dispatchFringe = dispatchFringe.contract(occ)
             current.occurrences.add(MatchJournal.Chunk.Entry(occ, true))
             occ.terminate()
         }
@@ -241,9 +240,8 @@ internal class StoreAwareJournalImpl(val state: ProcessingStateImpl, view: Match
 
 private fun RuleMatch.headJustifications(): Justs {
     val res: Justs = justsOf()
-    this.matchHeadKept().forEach { it.justifications()?.let { res.addAll(it) } }
-    this.matchHeadReplaced().forEach { it.justifications()?.let { res.addAll(it) } }
+    this.matchHeadKept().forEach { it.justifications().let { res.addAll(it) } }
+    this.matchHeadReplaced().forEach { it.justifications().let { res.addAll(it) } }
     return res
-//    return if (res.isEmpty) null else res
 }
 
diff --git a/reactor/Core/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java b/reactor/Core/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java
index cf614d34..e499f32c 100644
--- a/reactor/Core/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java
+++ b/reactor/Core/src/jetbrains/mps/logic/reactor/evaluation/ConstraintOccurrence.java
@@ -20,7 +20,7 @@ package jetbrains.mps.logic.reactor.evaluation;
 import gnu.trove.set.TIntSet;
 import jetbrains.mps.logic.reactor.logical.LogicalContext;
 import jetbrains.mps.logic.reactor.program.Constraint;
-import org.jetbrains.annotations.Nullable;
+import org.jetbrains.annotations.NotNull;
 
 import java.util.List;
 
@@ -37,7 +37,7 @@ public interface ConstraintOccurrence {
 
     LogicalContext logicalContext();
 
-    @Nullable
+    @NotNull
     TIntSet justifications();
 
 }