Trying to figure out how to encapsulate instance checking

compiler/expressions.go

@@ -618,7 +618,9 @@ func (fc *funcContext) translateExpr(expr ast.Expr) *expression {
 			if typesutil.IsJsPackage(obj.Pkg()) && obj.Name() == "InternalObject" {
 				return fc.translateExpr(e.Args[0])
 			}
-			fc.pkgCtx.DeclareDCEDep(obj)
+			if inst, has := fc.pkgCtx.Instances[f]; has {
+				fc.pkgCtx.DeclareDCEDepWithInstance(obj, inst)
+			}
 			return fc.translateCall(e, sig, fc.translateExpr(f))
 
 		case *ast.SelectorExpr:

compiler/internal/dce/collector.go

@@ -17,27 +17,24 @@ type Decl interface {
 // Collector is a tool to collect dependencies for a declaration
 // that'll be used in dead-code elimination (DCE).
 type Collector struct {
-	TypeInfo     *types.Info
-	dependencies map[string]struct{}
+	TypeInfo *types.Info
+	decl     *Info
 }
 
 // CollectDCEDeps captures a list of Go objects (types, functions, etc.)
 // the code translated inside f() depends on. Then sets those objects
 // as dependencies of the given dead-code elimination info.
 //
 // Only one CollectDCEDeps call can be active at a time.
-// This will overwrite any previous dependencies collected for the given DCE.
 func (c *Collector) CollectDCEDeps(decl Decl, f func()) {
-	if c.dependencies != nil {
+	if c.decl != nil {
 		panic(errors.New(`called CollectDCEDeps inside another CollectDCEDeps call`))
 	}
 
-	c.dependencies = make(map[string]struct{})
-	defer func() { c.dependencies = nil }()
+	c.decl = decl.Dce()
+	defer func() { c.decl = nil }()
 
 	f()
-
-	decl.Dce().setDeps(c.dependencies)
 }
 
 // DeclareDCEDep records that the code that is currently being transpiled
@@ -47,7 +44,7 @@ func (c *Collector) DeclareDCEDep(o types.Object) {
 }
 
 func (c *Collector) DeclareDCEDepWithInstance(o types.Object, inst types.Instance) {
-	if c.dependencies == nil {
+	if c.decl == nil {
 		return // Dependencies are not being collected.
 	}
 
@@ -62,5 +59,5 @@ func (c *Collector) DeclareDCEDepWithInstance(o types.Object, inst types.Instanc
 	if typesutil.IsMethod(o) {
 		qualifiedName += "~"
 	}
-	c.dependencies[qualifiedName] = struct{}{}
+	c.decl.addDep(qualifiedName)
 }

compiler/internal/dce/dce_test.go

@@ -256,7 +256,7 @@ func Test_Info_SetNameAndDep(t *testing.T) {
 					c.DeclareDCEDep(obj)
 				})
 				equal(t, len(d.Dce().deps), 1)
-				equal(t, d.Dce().deps[0], tt.wantDep)
+				equal(t, d.Dce().getDeps()[0], tt.wantDep)
 			})
 		}
 	})
@@ -508,6 +508,7 @@ func Test_Selector_SpecificMethods(t *testing.T) {
 
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
+			vetinari.Dce().deps = nil // reset deps
 			c.CollectDCEDeps(vetinari, func() {
 				for _, decl := range tt.deps {
 					c.DeclareDCEDep(decl.obj)

compiler/internal/dce/info.go

@@ -31,7 +31,7 @@ type Info struct {
 
 	// List of fully qualified (including package path) DCE symbol identifiers the
 	// symbol depends on for dead code elimination purposes.
-	deps []string
+	deps map[string]struct{}
 }
 
 // String gets a human-readable representation of the DCE info.
@@ -47,7 +47,7 @@ func (d *Info) String() string {
 	if len(d.methodFilter) > 0 {
 		fullName += `.` + d.methodFilter
 	}
-	return tags + fullName + ` -> [` + strings.Join(d.deps, `, `) + `]`
+	return tags + fullName + ` -> [` + strings.Join(d.getDeps(), `, `) + `]`
 }
 
 // unnamed returns true if SetName has not been called for this declaration.
@@ -91,14 +91,22 @@ func (d *Info) SetName(o types.Object) {
 	}
 }
 
-// setDeps sets the declaration dependencies used by DCE
+// addDep adds a declaration dependency used by DCE
 // for the declaration this DCE info is attached to.
-// This overwrites any prior set dependencies.
-func (d *Info) setDeps(depSet map[string]struct{}) {
-	deps := make([]string, 0, len(depSet))
-	for dep := range depSet {
-		deps = append(deps, dep)
+func (d *Info) addDep(dep string) {
+	if d.deps == nil {
+		d.deps = make(map[string]struct{})
+	}
+	d.deps[dep] = struct{}{}
+}
+
+func (id *Info) getDeps() []string {
+	deps := make([]string, len(id.deps))
+	i := 0
+	for dep := range id.deps {
+		deps[i] = dep
+		i++
 	}
 	sort.Strings(deps)
-	d.deps = deps
+	return deps
 }

compiler/internal/dce/selector.go

@@ -72,7 +72,7 @@ func (s *Selector[D]) AliveDecls() map[D]struct{} {
 
 		// Consider all decls the current one is known to depend on and possible add
 		// them to the live queue.
-		for _, dep := range dce.deps {
+		for _, dep := range dce.getDeps() {
 			if infos, ok := s.byFilter[dep]; ok {
 				delete(s.byFilter, dep)
 				for _, info := range infos {