Implement support for == operator on type params.

nevkontakte · nevkontakte · commit 3606e1e16923 · 2023-11-02T21:59:28.000Z
diff --git a/compiler/expressions.go b/compiler/expressions.go
@@ -316,8 +316,23 @@ func (fc *funcContext) translateExpr(expr ast.Expr) *expression {
 
 		t := fc.pkgCtx.TypeOf(e.X)
 		t2 := fc.pkgCtx.TypeOf(e.Y)
-		_, isInterface := t2.Underlying().(*types.Interface)
-		if isInterface || types.Identical(t, types.Typ[types.UntypedNil]) {
+
+		// Exact type param instantiations are not known at compile time, so
+		// some operators require special handling.
+		if (typesutil.IsTypeParam(t) || typesutil.IsTypeParam(t2)) &&
+			!(typesutil.IsInterface(t) || typesutil.IsInterface(t2)) { // == operator between an interface and other types is handled below.
+			if !types.Identical(t, t2) {
+				// This should never happen.
+				panic(bailout(fmt.Errorf("%s: binary operator %v is applied to different type param types %s and %s", fc.pkgCtx.fileSet.Position(e.Pos()), e.Op, t, t2)))
+			}
+
+			switch e.Op {
+			case token.EQL:
+				return fc.formatExpr("$equal(%e, %e, %s)", e.X, e.Y, fc.typeName(t))
+			}
+		}
+
+		if typesutil.IsInterface(t2) || types.Identical(t, types.Typ[types.UntypedNil]) {
 			t = t2
 		}
 
diff --git a/compiler/typesutil/typesutil.go b/compiler/typesutil/typesutil.go
@@ -130,6 +130,18 @@ func IsGeneric(t types.Type) bool {
 	}
 }
 
+// IsTypeParam returns true if the type is a type param.
+func IsTypeParam(t types.Type) bool {
+	_, ok := t.(*types.TypeParam)
+	return ok
+}
+
+// IsInterface returns true if the type is an interface.
+func IsInterface(t types.Type) bool {
+	_, ok := t.Underlying().(*types.Interface)
+	return ok && !IsTypeParam(t)
+}
+
 // IsMethod returns true if the passed object is a method.
 func IsMethod(o types.Object) bool {
 	f, ok := o.(*types.Func)
diff --git a/tests/gorepo/run.go b/tests/gorepo/run.go
@@ -150,6 +150,7 @@ var knownFails = map[string]failReason{
 	"fixedbugs/issue48536.go": {category: usesUnsupportedPackage, desc: "https://github.com/gopherjs/gopherjs/issues/1130"},
 	"fixedbugs/issue53600.go": {category: lowLevelRuntimeDifference, desc: "GopherJS println format is different from Go's"},
 	"typeparam/issue51733.go": {category: usesUnsupportedPackage, desc: "unsafe: uintptr to struct pointer conversion is unsupported"},
+	"typeparam/chans.go":      {category: neverTerminates, desc: "uses runtime.SetFinalizer() and runtime.GC()."},
 
 	// Failures related to the lack of generics support. Ideally, this section
 	// should be emptied once https://github.com/gopherjs/gopherjs/issues/1013 is
@@ -158,32 +159,19 @@ var knownFails = map[string]failReason{
 	"typeparam/absdiff2.go":          {category: generics, desc: "missing operator support for generic types"},
 	"typeparam/absdiff3.go":          {category: generics, desc: "missing operator support for generic types"},
 	"typeparam/boundmethod.go":       {category: generics, desc: "missing support for method expressions with a type param"},
-	"typeparam/chans.go":             {category: generics, desc: "missing support for the comparable type constraint"},
 	"typeparam/dictionaryCapture.go": {category: generics, desc: "missing support for basic literals with type params"},
 	"typeparam/double.go":            {category: generics, desc: "make() doesn't support generic slice types"},
-	"typeparam/equal.go":             {category: generics, desc: "missing support for the comparable type constraint"},
-	"typeparam/fact.go":              {category: generics, desc: "missing support for the comparable type constraint"},
-	"typeparam/graph.go":             {category: generics, desc: "missing operator support for generic types"},
-	"typeparam/index.go":             {category: generics, desc: "missing support for the comparable type constraint"},
+	"typeparam/fact.go":              {category: generics, desc: "missing support for basic literals with type params"},
 	"typeparam/index2.go":            {category: generics, desc: "missing index operator support for generic types"},
 	"typeparam/issue47258.go":        {category: generics, desc: "missing operator support for generic types"},
 	"typeparam/issue47716.go":        {category: generics, desc: "unsafe.Sizeof() doesn't work with generic types"},
-	"typeparam/issue48276a.go":       {category: generics, desc: "missing support for the comparable type constraint"},
 	"typeparam/issue48453.go":        {category: generics, desc: "make() doesn't support generic slice types"},
 	"typeparam/issue49295.go":        {category: generics, desc: "len() doesn't support generic pointer to array types"},
 	"typeparam/issue50193.go":        {category: generics, desc: "invalid print format for complex numbers"},
 	"typeparam/issue51303.go":        {category: generics, desc: "missing support for range over type parameter"},
-	"typeparam/issue51522a.go":       {category: generics, desc: "missing support for the comparable type constraint"},
-	"typeparam/issue51522b.go":       {category: generics, desc: "missing support for the comparable type constraint"},
 	"typeparam/list.go":              {category: generics, desc: "missing operator support for generic types"},
-	"typeparam/maps.go":              {category: generics, desc: "missing support for the comparable type constraint"},
-	"typeparam/metrics.go":           {category: generics, desc: "missing support for the comparable type constraint"},
 	"typeparam/nested.go":            {category: generics, desc: "missing comparison operator support for generic types"},
-	"typeparam/ordered.go":           {category: generics, desc: "missing support for the comparable type constraint"},
-	"typeparam/orderedmap.go":        {category: generics, desc: "missing support for the comparable type constraint"},
-	"typeparam/sets.go":              {category: generics, desc: "missing support for the comparable type constraint"},
 	"typeparam/slices.go":            {category: generics, desc: "missing operator support for generic types"},
-	"typeparam/subdict.go":           {category: generics, desc: "missing support for the comparable type constraint"},
 	"typeparam/typeswitch2.go":       {category: generics, desc: "complex types have different print() format"},
 	"typeparam/typeswitch3.go":       {category: generics, desc: "missing support for type switching on generic types"},
 	"typeparam/typeswitch5.go":       {category: generics, desc: "different print() format for floating point types"},
