start using go/types.Func.Signature

Guaranteed to return a *types.Signature, so no need to type assert.

internal/ctrlflow/trash.go

@@ -174,7 +174,7 @@ func isGenericType(p types.Type) bool {
 
 // isSupportedSig checks that the function is not generic and all parameters can be generated using valueGenerators
 func isSupportedSig(m *types.Func) bool {
-	sig := m.Type().(*types.Signature)
+	sig := m.Signature()
 	if isGenericType(sig) {
 		return false
 	}
@@ -430,7 +430,7 @@ func (t *trashGenerator) generateCall(vars map[string]*definedVar) ast.Stmt {
 
 	var args []ast.Expr
 
-	targetSig := targetFunc.Type().(*types.Signature)
+	targetSig := targetFunc.Signature()
 	params := targetSig.Params()
 	for i := 0; i < params.Len(); i++ {
 		param := params.At(i)

internal/ssa2ast/func_test.go

@@ -59,7 +59,7 @@ func TestConvertSignature(t *testing.T) {
 		funcDecl.Body = nil
 
 		funcObj := info.Defs[funcDecl.Name].(*types.Func)
-		funcDeclConverted, err := conv.convertSignatureToFuncDecl(funcObj.Name(), funcObj.Type().(*types.Signature))
+		funcDeclConverted, err := conv.convertSignatureToFuncDecl(funcObj.Name(), funcObj.Signature())
 		qt.Assert(t, qt.IsNil(err))
 		qt.Assert(t, qt.CmpEquals(funcDeclConverted, funcDecl, astCmpOpt))
 	}

main.go

@@ -1966,7 +1966,7 @@ func (tf *transformer) transformGoFile(file *ast.File) *ast.File {
 				return true
 			}
 
-			sign := obj.Type().(*types.Signature)
+			sign := obj.Signature()
 			if sign.Recv() == nil {
 				debugName = "func"
 			} else {

reflect.go

@@ -145,7 +145,7 @@ func (ri *reflectInspector) checkInterfaceMethod(m *types.Func) {
 
 	maps.Copy(reflectParams, ri.result.ReflectAPIs[m.FullName()])
 
-	sig := m.Type().(*types.Signature)
+	sig := m.Signature()
 	if m.Exported() {
 		ri.checkMethodSignature(reflectParams, sig)
 	}