Forbid pass non-node object to print() (#13293)

src/language-js/print/type-parameters.js

@@ -112,8 +112,11 @@ function printTypeParameter(path, options, print) {
   const node = path.getValue();
   const parts = [];
   const parent = path.getParentNode();
+
+  const name = node.type === "TSTypeParameter" ? print("name") : node.name;
+
   if (parent.type === "TSMappedType") {
-    parts.push("[", print("name"));
+    parts.push("[", name);
     if (node.constraint) {
       parts.push(" in ", print("constraint"));
     }
@@ -139,7 +142,7 @@ function printTypeParameter(path, options, print) {
     parts.push("out ");
   }
 
-  parts.push(print("name"));
+  parts.push(name);
 
   if (node.bound) {
     parts.push(": ", print("bound"));

src/language-js/printer-estree.js

@@ -89,12 +89,21 @@ import { printLiteral } from "./print/literal.js";
 import { printDecorators } from "./print/decorators.js";
 
 function genericPrint(path, options, print, args) {
+  const node = path.getValue();
+
+  if (node === undefined || node === null) {
+    return "";
+  }
+
+  if (process.env.NODE_ENV !== "production") {
+    ensurePrintingNode(path);
+  }
+
   const printed = printPathNoParens(path, options, print, args);
   if (!printed) {
     return "";
   }
 
-  const node = path.getValue();
   const { type } = node;
   // Their decorators are handled themselves, and they can't have parentheses
   if (
@@ -170,14 +179,6 @@ function printPathNoParens(path, options, print, args) {
   const node = path.getValue();
   const semi = options.semi ? ";" : "";
 
-  if (!node) {
-    return "";
-  }
-
-  if (typeof node === "string") {
-    return node;
-  }
-
   for (const printer of [
     printLiteral,
     printHtmlBinding,
@@ -778,7 +779,7 @@ function printPathNoParens(path, options, print, args) {
     case "TaggedTemplateExpression":
       return [print("tag"), print("typeParameters"), print("quasi")];
     case "PrivateIdentifier":
-      return ["#", print("name")];
+      return ["#", node.name];
     case "PrivateName":
       return ["#", print("id")];
 
@@ -846,6 +847,46 @@ function canAttachComment(node) {
   );
 }
 
+function ensurePrintingNode(path) {
+  let name = path.getName();
+
+  // AST root
+  if (name === null) {
+    return;
+  }
+
+  if (typeof name === "number") {
+    /*
+    Nodes in array are stored in path.stack like
+
+    ```js
+    [
+      parentNode,
+      property, // <-
+      array,
+      index,
+      node,
+    ]
+    ```
+    */
+    name = path.stack[path.stack.length - 4];
+  }
+
+  const parent = path.getParentNode();
+  const visitorKeys = getVisitorKeys(parent);
+  if (visitorKeys.includes(name)) {
+    return;
+  }
+
+  /* istanbul ignore next */
+  throw Object.assign(new Error("Calling `print()` on non-node object."), {
+    parentNode: parent,
+    allowedProperties: visitorKeys,
+    printingProperty: name,
+    printingValue: path.getValue(),
+  });
+}
+
 const printer = {
   preprocess,
   print: genericPrint,

src/language-js/traverse/visitor-keys.evaluate.js

@@ -10,7 +10,7 @@ const angularVisitorKeys = {
   NGQuotedExpression: [],
   NGMicrosyntax: ["body"],
   NGMicrosyntaxKey: [],
-  NGMicrosyntaxExpression: ["expression", "name"],
+  NGMicrosyntaxExpression: ["expression", "alias"],
   NGMicrosyntaxKeyedExpression: ["key", "expression"],
   NGMicrosyntaxLet: ["key", "value"],
   NGMicrosyntaxAs: ["key", "alias"],
@@ -46,6 +46,11 @@ const additionalVisitorKeys = {
   ArrowFunctionExpression: ["predicate"],
   DeclareFunction: ["predicate"],
   FunctionDeclaration: ["predicate"],
+  ClassProperty: ["variance"],
+  ClassPrivateProperty: ["variance"],
+  EnumBooleanMember: ["init"],
+
+  Property: ["decorators"],
 };
 
 export default unionVisitorKeys([

tests/unit/__snapshots__/visitor-keys.js.snap

@@ -123,12 +123,14 @@ exports[`visitor keys estree 1`] = `
     "value",
     "decorators",
     "typeAnnotation",
+    "variance",
   ],
   "ClassProperty": [
     "key",
     "value",
     "typeAnnotation",
     "decorators",
+    "variance",
   ],
   "ConditionalExpression": [
     "test",
@@ -212,6 +214,7 @@ exports[`visitor keys estree 1`] = `
   ],
   "EnumBooleanMember": [
     "id",
+    "init",
   ],
   "EnumDeclaration": [
     "id",
@@ -468,7 +471,7 @@ exports[`visitor keys estree 1`] = `
   ],
   "NGMicrosyntaxExpression": [
     "expression",
-    "name",
+    "alias",
   ],
   "NGMicrosyntaxKey": [],
   "NGMicrosyntaxKeyedExpression": [
@@ -597,6 +600,7 @@ exports[`visitor keys estree 1`] = `
   "Property": [
     "key",
     "value",
+    "decorators",
   ],
   "PropertyDefinition": [
     "decorators",