Safe equality for core classes:

Name, Symbol, Denotation, Type.

This uncovered two nonsensical comparisons, one in CollectEntryPoints,
the other in DottyBackendInterface.

4 files changed, 8 insertions, 0 deletions

diff --git a/src/dotty/tools/dotc/core/Denotations.scala b/src/dotty/tools/dotc/core/Denotations.scala
index 080e8a39b..69624b01a 100644
--- a/src/dotty/tools/dotc/core/Denotations.scala
+++ b/src/dotty/tools/dotc/core/Denotations.scala
@@ -70,6 +70,8 @@ import Decorators.SymbolIteratorDecorator
  */
 object Denotations {
 
+  implicit def eqDenotation: Eq[Denotation, Denotation] = Eq
+
   /** A denotation is the result of resolving
    *  a name (either simple identifier or select) during a given period.
    *
diff --git a/src/dotty/tools/dotc/core/Names.scala b/src/dotty/tools/dotc/core/Names.scala
index 10eef16c1..223d95045 100644
--- a/src/dotty/tools/dotc/core/Names.scala
+++ b/src/dotty/tools/dotc/core/Names.scala
@@ -26,6 +26,8 @@ object Names {
     def toTermName: TermName
   }
 
+  implicit def eqName: Eq[Name, Name] = Eq
+
   /** A name is essentially a string, with three differences
    *  1. Names belong in one of two name spaces: they are type names or term names.
    *     Term names have a sub-category of "local" field names.
diff --git a/src/dotty/tools/dotc/core/Symbols.scala b/src/dotty/tools/dotc/core/Symbols.scala
index d40acdfa7..473f107cb 100644
--- a/src/dotty/tools/dotc/core/Symbols.scala
+++ b/src/dotty/tools/dotc/core/Symbols.scala
@@ -361,6 +361,8 @@ trait Symbols { this: Context =>
 
 object Symbols {
 
+  implicit def eqSymbol: Eq[Symbol, Symbol] = Eq
+
   /** A Symbol represents a Scala definition/declaration or a package.
    *  @param coord  The coordinates of the symbol (a position or an index)
    *  @param id     A unique identifier of the symbol (unique per ContextBase)
diff --git a/src/dotty/tools/dotc/core/Types.scala b/src/dotty/tools/dotc/core/Types.scala
index 114e6c908..71ea6d2b3 100644
--- a/src/dotty/tools/dotc/core/Types.scala
+++ b/src/dotty/tools/dotc/core/Types.scala
@@ -38,6 +38,8 @@ object Types {
 
   @sharable private var nextId = 0
 
+  implicit def eqType: Eq[Type, Type] = Eq
+
   /** The class of types.
    *  The principal subclasses and sub-objects are as follows:
    *