From 97b7768890eb7fc7d731500ad140b7f63235dbaa Mon Sep 17 00:00:00 2001
From: Andrey Breslav <andrey.breslav@jetbrains.com>
Date: Mon, 23 Jun 2014 15:39:46 +0400
Subject: [PATCH] JetTypeChecker refactored: duplicate methods replaced by
 instance management

---
 .../jet/lang/resolve/OverridingUtil.java      |  4 +-
 .../lang/types/checker/JetTypeChecker.java    | 40 ++++++++-----------
 2 files changed, 19 insertions(+), 25 deletions(-)

diff --git a/core/descriptors/src/org/jetbrains/jet/lang/resolve/OverridingUtil.java b/core/descriptors/src/org/jetbrains/jet/lang/resolve/OverridingUtil.java
index 942ddd72841..09c3abc67a9 100644
--- a/core/descriptors/src/org/jetbrains/jet/lang/resolve/OverridingUtil.java
+++ b/core/descriptors/src/org/jetbrains/jet/lang/resolve/OverridingUtil.java
@@ -165,7 +165,7 @@ public class OverridingUtil {
 
             if (superReturnType != null && subReturnType != null) {
                 boolean bothErrors = subReturnType.isError() && superReturnType.isError();
-                if (!bothErrors && !JetTypeChecker.DEFAULT.isSubtypeOf(subReturnType, superReturnType, localEqualityAxioms)) {
+                if (!bothErrors && !JetTypeChecker.withAxioms(localEqualityAxioms).isSubtypeOf(subReturnType, superReturnType)) {
                     return OverrideCompatibilityInfo.returnTypeMismatch(superReturnType, subReturnType);
                 }
             }
@@ -203,7 +203,7 @@ public class OverridingUtil {
             @NotNull JetTypeChecker.TypeConstructorEquality axioms
     ) {
         boolean bothErrors = typeInSuper.isError() && typeInSub.isError();
-        if (!bothErrors && !JetTypeChecker.DEFAULT.equalTypes(typeInSuper, typeInSub, axioms)) {
+        if (!bothErrors && !JetTypeChecker.withAxioms(axioms).equalTypes(typeInSuper, typeInSub)) {
             return false;
         }
         return true;
diff --git a/core/descriptors/src/org/jetbrains/jet/lang/types/checker/JetTypeChecker.java b/core/descriptors/src/org/jetbrains/jet/lang/types/checker/JetTypeChecker.java
index 7f52422fc7b..aaa4cc0a3b9 100644
--- a/core/descriptors/src/org/jetbrains/jet/lang/types/checker/JetTypeChecker.java
+++ b/core/descriptors/src/org/jetbrains/jet/lang/types/checker/JetTypeChecker.java
@@ -22,39 +22,33 @@ import org.jetbrains.jet.lang.types.TypeConstructor;
 
 public class JetTypeChecker {
 
-    public static final JetTypeChecker DEFAULT = new JetTypeChecker();
     public interface TypeConstructorEquality {
         boolean equals(@NotNull TypeConstructor a, @NotNull TypeConstructor b);
     }
 
-    private JetTypeChecker() {
-    }
-
-    public boolean isSubtypeOf(@NotNull JetType subtype, @NotNull JetType supertype) {
-        return TYPE_CHECKER.isSubtypeOf(subtype, supertype);
-    }
-
-    public boolean isSubtypeOf(@NotNull JetType subtype, @NotNull JetType supertype, @NotNull TypeConstructorEquality equalityAxioms) {
-        return createWithAxioms(equalityAxioms).isSubtypeOf(subtype, supertype);
-    }
-
-    public boolean equalTypes(@NotNull JetType a, @NotNull JetType b) {
-        return TYPE_CHECKER.equalTypes(a, b);
-    }
-
-    public boolean equalTypes(@NotNull JetType a, @NotNull JetType b, @NotNull TypeConstructorEquality equalityAxioms) {
-        return createWithAxioms(equalityAxioms).equalTypes(a, b);
-    }
+    public static final JetTypeChecker DEFAULT = new JetTypeChecker(new TypeCheckingProcedure(new TypeCheckerTypingConstraints()));
 
     @NotNull
-    private static TypeCheckingProcedure createWithAxioms(@NotNull final TypeConstructorEquality equalityAxioms) {
-        return new TypeCheckingProcedure(new TypeCheckerTypingConstraints() {
+    public static JetTypeChecker withAxioms(@NotNull final TypeConstructorEquality equalityAxioms) {
+        return new JetTypeChecker(new TypeCheckingProcedure(new TypeCheckerTypingConstraints() {
             @Override
             public boolean assertEqualTypeConstructors(@NotNull TypeConstructor constructor1, @NotNull TypeConstructor constructor2) {
                 return constructor1.equals(constructor2) || equalityAxioms.equals(constructor1, constructor2);
             }
-        });
+        }));
     }
 
-    private static final TypeCheckingProcedure TYPE_CHECKER = new TypeCheckingProcedure(new TypeCheckerTypingConstraints());
+    private final TypeCheckingProcedure procedure;
+
+    private JetTypeChecker(@NotNull TypeCheckingProcedure procedure) {
+        this.procedure = procedure;
+    }
+
+    public boolean isSubtypeOf(@NotNull JetType subtype, @NotNull JetType supertype) {
+        return procedure.isSubtypeOf(subtype, supertype);
+    }
+
+    public boolean equalTypes(@NotNull JetType a, @NotNull JetType b) {
+        return procedure.equalTypes(a, b);
+    }
 }