Remove explicit "implements Object" from classes; it is implicit

thegridman · Jul 26, 2023 · fee2073 · fee2073
1 parent 773394f
commit fee2073
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Showing 2 changed files with 22 additions and 8 deletions.
diff --git a/javatools/src/main/java/org/xvm/asm/constants/TypeConstant.java b/javatools/src/main/java/org/xvm/asm/constants/TypeConstant.java
@@ -2475,8 +2475,6 @@ private TypeConstant[] createContributionList(
         switch (struct.getFormat())
             {
             case PACKAGE:
-                assert cContribs != 0 || ((PackageStructure) struct).isModuleImport();
-                // fall through
             case MODULE:
             case ENUMVALUE:
             case ENUM:
@@ -2490,8 +2488,8 @@ private TypeConstant[] createContributionList(
                 // format)
                 typeRebase = (TypeConstant) pool.register(struct.getRebaseType());
 
-                // next up, for any class type (other than Object itself), there may be an "extends"
-                // contribution that specifies another class
+                // next up, for any class type, there may be an "extends" contribution that
+                // specifies a "super" class
                 Contribution contrib = iContrib < cContribs ? listContribs.get(iContrib) : null;
                 boolean fExtends = contrib != null && contrib.getComposition() == Composition.Extends;
 
@@ -2501,6 +2499,9 @@ private TypeConstant[] createContributionList(
                         {
                         log(errs, Severity.ERROR, VE_EXTENDS_EXPECTED, constId.getPathString());
                         }
+
+                    // a class hierarchy root implicitly implements the root Object interface
+                    ++cContribs;
                     break;
                     }
 
@@ -2671,8 +2672,20 @@ else if (!fInto)
         // the list to do
         for ( ; iContrib < cContribs; ++iContrib)
             {
-            Contribution contrib     = listContribs.get(iContrib);
-            TypeConstant typeContrib = aContribType[iContrib];
+            Contribution contrib;
+            TypeConstant typeContrib;
+            if (iContrib < listContribs.size())
+                {
+                contrib     = listContribs.get(iContrib);
+                typeContrib = aContribType[iContrib];
+                }
+            else
+                {
+                // it's the implicit "implements Object" contribution
+                assert iContrib == listContribs.size();
+                typeContrib = pool.typeObject();
+                contrib     = struct.new Contribution(Composition.Implements, typeContrib);
+                }
 
             switch (contrib.getComposition())
                 {

diff --git a/javatools/src/main/java/org/xvm/compiler/ast/TypeCompositionStatement.java b/javatools/src/main/java/org/xvm/compiler/ast/TypeCompositionStatement.java
@@ -951,7 +951,7 @@ else if ((nSpecified & nBits) != 0)
         // interface    n   [8]     n [8]       n [9]
         //
         // [1] module/package/const/enum may explicitly extend a class or a const; otherwise
-        //    implements Object
+        //    implements Object (implicit: "Object" is not added to the structure)
         // [2] package may import a module
         // [3] class may explicitly extend a class; otherwise implements Object (the one exception is
         //     Object itself, which does NOT implement itself)
@@ -1002,7 +1002,8 @@ else if ((nSpecified & nBits) != 0)
                     break;
 
                 default:
-                    typeDefaultImpl = pool.typeObject();
+                    // it's implied that the default impl is pool.typeObject()
+                    typeDefaultImpl = null;
                     break;
                 }
             }