- Added method Type.isError

3 files changed, 25 insertions, 6 deletions

diff --git a/sources/scalac/symtab/Type.java b/sources/scalac/symtab/Type.java
index 8fb835786b..bbd0455423 100644
--- a/sources/scalac/symtab/Type.java
+++ b/sources/scalac/symtab/Type.java
@@ -154,7 +154,7 @@ public class Type implements Modifiers, Kinds, TypeTags, EntryTags {
                 "illegal cyclic reference involving " + rebind);
             sym = rebind.rebindSym();
         }
-        if (pre.isStable() || pre == ErrorType) {
+        if (pre.isStable() || pre.isError()) {
             return new ExtSingleType(pre, sym);
         } else {
             throw new Type.Malformed(pre, sym.nameString() + ".type");
@@ -197,7 +197,7 @@ public class Type implements Modifiers, Kinds, TypeTags, EntryTags {
     }
 
     public static Type typeRef(Type pre, Symbol sym, Type[] args) {
-        if (!pre.isLegalPrefix() && pre != ErrorType)
+        if (!pre.isLegalPrefix() && !pre.isError())
             throw new Type.Malformed(pre, sym.nameString());
         rebind:
         if (sym.isAbstractType()) {
@@ -225,7 +225,7 @@ public class Type implements Modifiers, Kinds, TypeTags, EntryTags {
         return new ExtTypeRef(pre, sym, args);
     }
     private static boolean isLegalTypeRef(Type pre, Symbol sym, Type[] args) {
-        if (!pre.isLegalPrefix() && pre != ErrorType) return false;
+        if (!pre.isLegalPrefix() && !pre.isError()) return false;
         if (!sym.isType() && !sym.isError()) return false;
         // !!! return args.length == 0 || args.length == sym.typeParams().length;
         return true;
@@ -642,6 +642,25 @@ public class Type implements Modifiers, Kinds, TypeTags, EntryTags {
 
 // Tests --------------------------------------------------------------------
 
+    /** Is this type a an error type?
+     */
+    public boolean isError() {
+        switch (this) {
+        case ErrorType:
+            return true;
+        case ThisType(Symbol clasz):
+            return clasz.isError();
+        case SingleType(_, Symbol symbol):
+            return symbol.isError();
+        case TypeRef(_, Symbol symbol, _):
+            return symbol.isError();
+        case CompoundType(Type[] parts, Scope members):
+            return symbol().isError();
+        default:
+            return false;
+        }
+    }
+
     /** Is this type a this type or singleton type?
      */
     public boolean isStable() {
diff --git a/sources/scalac/symtab/classfile/CLRClassParser.java b/sources/scalac/symtab/classfile/CLRClassParser.java
index 8ac897cca5..0ec6df58a4 100644
--- a/sources/scalac/symtab/classfile/CLRClassParser.java
+++ b/sources/scalac/symtab/classfile/CLRClassParser.java
@@ -275,7 +275,7 @@ public class CLRClassParser extends SymbolLoader {
 	assert type != null;
 	scalac.symtab.Type res =
 	    make.classType(type.FullName.replace('+', '.'));
-	if (res == scalac.symtab.Type.ErrorType)
+	if (res.isError())
 	    global.error("unknown class reference " + type.FullName);
 	return res;
     }
diff --git a/sources/scalac/typechecker/RefCheck.java b/sources/scalac/typechecker/RefCheck.java
index 92290a4317..c7e2572d72 100644
--- a/sources/scalac/typechecker/RefCheck.java
+++ b/sources/scalac/typechecker/RefCheck.java
@@ -277,7 +277,7 @@ public class RefCheck extends Transformer implements Modifiers, Kinds {
     }
 
     void overrideError(int pos, Symbol member, Symbol other, String msg) {
-	if (other.type() != Type.ErrorType && member.type() != Type.ErrorType)
+	if (!other.type().isError() && !member.type().isError())
 	    unit.error(pos,
 		"error overriding " + other + other.locationString() +
 		";\n " + member + member.locationString() + " " + msg);
@@ -285,7 +285,7 @@ public class RefCheck extends Transformer implements Modifiers, Kinds {
 
     void overrideTypeError(int pos, Symbol member, Symbol other, Type site,
 			   boolean lobound) {
-	if (other.type() != Type.ErrorType && member.type() != Type.ErrorType) {
+	if (!other.type().isError() && !member.type().isError()) {
 	    Type memberInfo = lobound ? site.memberLoBound(member)
 		: normalizedInfo(site, member);
 	    Type otherInfo = lobound ? site.memberLoBound(other)