Add AncestorN helper

flimzy · flimzy · commit cd7ebadcf986 · 2023-08-04T13:52:25.000+02:00
diff --git a/analysis/passes/jsobjectptr/jsobjectptr.go b/analysis/passes/jsobjectptr/jsobjectptr.go
@@ -32,7 +32,10 @@ func run(pass *analysis.Pass) (interface{}, error) {
 		if !internal.Is_jsObject(pass, node) {
 			return true
 		}
-		parent := stack[len(stack)-2]
+		parent, ok := internal.AncestorN(stack, 1)
+		if !ok {
+			return true
+		}
 		switch pt := parent.(type) {
 		case *ast.StarExpr:
 			return true
diff --git a/internal/jsobject.go b/internal/jsobject.go
@@ -43,3 +43,13 @@ func Is_jsObject(pass *analysis.Pass, node ast.Node) bool {
 	}
 	return pkg.Path() == "github.com/gopherjs/gopherjs/js"
 }
+
+// AncestorN returns the nth ancestor from stack, and true, or nil and false if
+// it does not exist.
+func AncestorN(stack []ast.Node, n int) (ast.Node, bool) {
+	l := len(stack)
+	if n > l {
+		return nil, false
+	}
+	return stack[l-(n+1)], true
+}

Original file line number	Diff line number	Diff line change
`@@ -43,3 +43,13 @@ func Is_jsObject(pass *analysis.Pass, node ast.Node) bool {`
`43`	`43`	`}`
`44`	`44`	`return pkg.Path() == "github.com/gopherjs/gopherjs/js"`
`45`	`45`	`}`
	`46`	`+`
	`47`	`+// AncestorN returns the nth ancestor from stack, and true, or nil and false if`
	`48`	`+// it does not exist.`
	`49`	`+func AncestorN(stack []ast.Node, n int) (ast.Node, bool) {`
	`50`	`+ l := len(stack)`
	`51`	`+ if n > l {`
	`52`	`+ return nil, false`
	`53`	`+ }`
	`54`	`+ return stack[l-(n+1)], true`
	`55`	`+}`