diff --git a/packages/babel-parser/src/parser/statement.js b/packages/babel-parser/src/parser/statement.js
index 3e950d26578b..04008adace8e 100644
--- a/packages/babel-parser/src/parser/statement.js
+++ b/packages/babel-parser/src/parser/statement.js
@@ -1177,6 +1177,7 @@ export default class StatementParser extends ExpressionParser {
     this.state.classLevel++;
 
     const state = { hadConstructor: false };
+    const privateNames: Set<string> = new Set();
     let decorators: N.Decorator[] = [];
     const classBody: N.ClassBody = this.startNode();
     classBody.body = [];
@@ -1212,7 +1213,13 @@ export default class StatementParser extends ExpressionParser {
           decorators = [];
         }
 
-        this.parseClassMember(classBody, member, state, constructorAllowsSuper);
+        this.parseClassMember(
+          classBody,
+          member,
+          state,
+          constructorAllowsSuper,
+          privateNames,
+        );
 
         if (
           member.kind === "constructor" &&
@@ -1244,6 +1251,7 @@ export default class StatementParser extends ExpressionParser {
     member: N.ClassMember,
     state: { hadConstructor: boolean },
     constructorAllowsSuper: boolean,
+    privateNames: Set<string>,
   ): void {
     let isStatic = false;
     const containsEsc = this.state.containsEsc;
@@ -1291,6 +1299,7 @@ export default class StatementParser extends ExpressionParser {
       state,
       isStatic,
       constructorAllowsSuper,
+      privateNames,
     );
   }
 
@@ -1300,6 +1309,7 @@ export default class StatementParser extends ExpressionParser {
     state: { hadConstructor: boolean },
     isStatic: boolean,
     constructorAllowsSuper: boolean,
+    privateNames: Set<string>,
   ) {
     const publicMethod: $FlowSubtype<N.ClassMethod> = member;
     const privateMethod: $FlowSubtype<N.ClassPrivateMethod> = member;
@@ -1318,7 +1328,13 @@ export default class StatementParser extends ExpressionParser {
 
       if (method.key.type === "PrivateName") {
         // Private generator method
-        this.pushClassPrivateMethod(classBody, privateMethod, true, false);
+        this.pushClassPrivateMethod(
+          classBody,
+          privateMethod,
+          true,
+          false,
+          privateNames,
+        );
         return;
       }
 
@@ -1350,7 +1366,13 @@ export default class StatementParser extends ExpressionParser {
       method.kind = "method";
 
       if (isPrivate) {
-        this.pushClassPrivateMethod(classBody, privateMethod, false, false);
+        this.pushClassPrivateMethod(
+          classBody,
+          privateMethod,
+          false,
+          false,
+          privateNames,
+        );
         return;
       }
 
@@ -1385,7 +1407,7 @@ export default class StatementParser extends ExpressionParser {
       );
     } else if (this.isClassProperty()) {
       if (isPrivate) {
-        this.pushClassPrivateProperty(classBody, privateProp);
+        this.pushClassPrivateProperty(classBody, privateProp, privateNames);
       } else {
         this.pushClassProperty(classBody, publicProp);
       }
@@ -1409,6 +1431,7 @@ export default class StatementParser extends ExpressionParser {
           privateMethod,
           isGenerator,
           true,
+          privateNames,
         );
       } else {
         if (this.isNonstaticConstructor(publicMethod)) {
@@ -1441,7 +1464,13 @@ export default class StatementParser extends ExpressionParser {
 
       if (method.key.type === "PrivateName") {
         // private getter/setter
-        this.pushClassPrivateMethod(classBody, privateMethod, false, false);
+        this.pushClassPrivateMethod(
+          classBody,
+          privateMethod,
+          false,
+          false,
+          privateNames,
+        );
       } else {
         if (this.isNonstaticConstructor(publicMethod)) {
           this.raise(
@@ -1463,7 +1492,7 @@ export default class StatementParser extends ExpressionParser {
     } else if (this.isLineTerminator()) {
       // an uninitialized class property (due to ASI, since we don't otherwise recognize the next token)
       if (isPrivate) {
-        this.pushClassPrivateProperty(classBody, privateProp);
+        this.pushClassPrivateProperty(classBody, privateProp, privateNames);
       } else {
         this.pushClassProperty(classBody, publicProp);
       }
@@ -1511,8 +1540,10 @@ export default class StatementParser extends ExpressionParser {
   pushClassPrivateProperty(
     classBody: N.ClassBody,
     prop: N.ClassPrivateProperty,
+    privateNames: Set<string>,
   ) {
     this.expectPlugin("classPrivateProperties", prop.key.start);
+    this.assertNoDuplicatePrivateName(prop, privateNames);
     classBody.body.push(this.parseClassPrivateProperty(prop));
   }
 
@@ -1542,8 +1573,10 @@ export default class StatementParser extends ExpressionParser {
     method: N.ClassPrivateMethod,
     isGenerator: boolean,
     isAsync: boolean,
+    privateNames: Set<string>,
   ): void {
     this.expectPlugin("classPrivateMethods", method.key.start);
+    this.assertNoDuplicatePrivateName(method, privateNames);
     classBody.body.push(
       this.parseMethod(
         method,
@@ -1557,6 +1590,37 @@ export default class StatementParser extends ExpressionParser {
     );
   }
 
+  assertNoDuplicatePrivateName(
+    methodOrProp: N.ClassPrivateMethod | N.ClassPrivateProperty,
+    privateNames: Set<string>,
+  ) {
+    let isDuplicate = false;
+    const { name } = methodOrProp.key.id;
+
+    if (
+      methodOrProp.type === "ClassPrivateProperty" ||
+      methodOrProp.kind === "method"
+    ) {
+      isDuplicate = privateNames.has(name);
+    } else {
+      // Accessors can have the same name for get and set
+      const { kind } = methodOrProp;
+      const otherKind = kind === "get" ? "set" : "get";
+
+      isDuplicate = privateNames.has(name);
+      if (isDuplicate && privateNames.has(`${otherKind} ${name}`)) {
+        isDuplicate = privateNames.has(`${kind} ${name}`);
+      }
+
+      privateNames.add(`${kind} ${name}`);
+    }
+    privateNames.add(name);
+
+    if (isDuplicate) {
+      this.raise(methodOrProp.key.start, `Duplicate private name #${name}`);
+    }
+  }
+
   // Overridden in typescript.js
   parsePostMemberNameModifiers(
     // eslint-disable-next-line no-unused-vars
diff --git a/packages/babel-parser/src/plugins/flow.js b/packages/babel-parser/src/plugins/flow.js
index 024a21baa5ab..6371317844f4 100644
--- a/packages/babel-parser/src/plugins/flow.js
+++ b/packages/babel-parser/src/plugins/flow.js
@@ -2107,8 +2107,6 @@ export default (superClass: Class<Parser>): Class<Parser> =>
     pushClassPrivateMethod(
       classBody: N.ClassBody,
       method: N.ClassPrivateMethod,
-      isGenerator: boolean,
-      isAsync: boolean,
     ): void {
       if ((method: $FlowFixMe).variance) {
         this.unexpected((method: $FlowFixMe).variance.start);
@@ -2118,7 +2116,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         method.typeParameters = this.flowParseTypeParameterDeclaration();
       }
 
-      super.pushClassPrivateMethod(classBody, method, isGenerator, isAsync);
+      super.pushClassPrivateMethod(...arguments);
     }
 
     // parse a the super class type parameters and implements
diff --git a/packages/babel-parser/src/plugins/typescript/index.js b/packages/babel-parser/src/plugins/typescript/index.js
index 5d6922d329eb..de95ff30a726 100644
--- a/packages/babel-parser/src/plugins/typescript/index.js
+++ b/packages/babel-parser/src/plugins/typescript/index.js
@@ -1795,16 +1795,11 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       return this.tsParseModifier(["public", "protected", "private"]);
     }
 
-    parseClassMember(
-      classBody: N.ClassBody,
-      member: any,
-      state: { hadConstructor: boolean },
-      constructorAllowsSuper: boolean,
-    ): void {
+    parseClassMember(classBody: N.ClassBody, member: any): void {
       const accessibility = this.parseAccessModifier();
       if (accessibility) member.accessibility = accessibility;
 
-      super.parseClassMember(classBody, member, state, constructorAllowsSuper);
+      super.parseClassMember(...arguments);
     }
 
     parseClassMemberWithIsStatic(
@@ -1812,7 +1807,6 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       member: any,
       state: { hadConstructor: boolean },
       isStatic: boolean,
-      constructorAllowsSuper: boolean,
     ): void {
       const methodOrProp: N.ClassMethod | N.ClassProperty = member;
       const prop: N.ClassProperty = member;
@@ -1853,13 +1847,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         return;
       }
 
-      super.parseClassMemberWithIsStatic(
-        classBody,
-        member,
-        state,
-        isStatic,
-        constructorAllowsSuper,
-      );
+      super.parseClassMemberWithIsStatic(...arguments);
     }
 
     parsePostMemberNameModifiers(
@@ -2035,12 +2023,10 @@ export default (superClass: Class<Parser>): Class<Parser> =>
     pushClassPrivateMethod(
       classBody: N.ClassBody,
       method: N.ClassPrivateMethod,
-      isGenerator: boolean,
-      isAsync: boolean,
     ): void {
       const typeParameters = this.tsTryParseTypeParameters();
       if (typeParameters) method.typeParameters = typeParameters;
-      super.pushClassPrivateMethod(classBody, method, isGenerator, isAsync);
+      super.pushClassPrivateMethod(...arguments);
     }
 
     parseClassSuper(node: N.Class): void {
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-accessor-method/input.js b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-accessor-method/input.js
new file mode 100644
index 000000000000..00d50846e973
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-accessor-method/input.js
@@ -0,0 +1,4 @@
+class A {
+  get #x() {}
+  #x() {}
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-accessor-method/options.json b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-accessor-method/options.json
new file mode 100644
index 000000000000..d8cfeb86ac86
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-accessor-method/options.json
@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    "classPrivateMethods",
+    "classPrivateProperties"
+  ],
+  "throws": "Duplicate private name #x (3:2)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-field-method/input.js b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-field-method/input.js
new file mode 100644
index 000000000000..6dde01adc90e
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-field-method/input.js
@@ -0,0 +1,4 @@
+class A {
+  #x;
+  #x() {}
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-field-method/options.json b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-field-method/options.json
new file mode 100644
index 000000000000..d8cfeb86ac86
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-field-method/options.json
@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    "classPrivateMethods",
+    "classPrivateProperties"
+  ],
+  "throws": "Duplicate private name #x (3:2)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-accessor/input.js b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-accessor/input.js
new file mode 100644
index 000000000000..b1d19924d288
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-accessor/input.js
@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  get #x() {}
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-accessor/options.json b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-accessor/options.json
new file mode 100644
index 000000000000..b7d1abf9903b
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-accessor/options.json
@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    "classPrivateMethods",
+    "classPrivateProperties"
+  ],
+  "throws": "Duplicate private name #x (3:6)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-field/input.js b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-field/input.js
new file mode 100644
index 000000000000..26122843af16
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-field/input.js
@@ -0,0 +1,4 @@
+class A {
+  #x() {}
+  #x;
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-field/options.json b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-field/options.json
new file mode 100644
index 000000000000..d8cfeb86ac86
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-methods/duplicated-method-field/options.json
@@ -0,0 +1,7 @@
+{
+  "plugins": [
+    "classPrivateMethods",
+    "classPrivateProperties"
+  ],
+  "throws": "Duplicate private name #x (3:2)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-different-placement/input.js b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-different-placement/input.js
new file mode 100644
index 000000000000..df22b36e0ae8
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-different-placement/input.js
@@ -0,0 +1,4 @@
+class A {
+  #x = 1;
+  static #x = 2;
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-different-placement/options.json b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-different-placement/options.json
new file mode 100644
index 000000000000..c446ed73a897
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-different-placement/options.json
@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    "classPrivateProperties"
+  ],
+  "throws": "Duplicate private name #x (3:9)"
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-same-placement/input.js b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-same-placement/input.js
new file mode 100644
index 000000000000..83ddd3d8a226
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-same-placement/input.js
@@ -0,0 +1,4 @@
+class A {
+  #x = 1;
+  #x = 2;
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-same-placement/options.json b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-same-placement/options.json
new file mode 100644
index 000000000000..c7707470a4f3
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/experimental/class-private-properties/duplicated-same-placement/options.json
@@ -0,0 +1,6 @@
+{
+  "plugins": [
+    "classPrivateProperties"
+  ],
+  "throws": "Duplicate private name #x (3:2)"
+}
\ No newline at end of file
diff --git a/scripts/tests/test262/test262_whitelist.txt b/scripts/tests/test262/test262_whitelist.txt
index 8f929fd51b80..e972f8e4a24b 100644
--- a/scripts/tests/test262/test262_whitelist.txt
+++ b/scripts/tests/test262/test262_whitelist.txt
@@ -396,8 +396,6 @@ language/expressions/async-arrow-function/early-errors-arrow-await-in-formals-de
 language/expressions/async-arrow-function/early-errors-arrow-await-in-formals-default.js(strict mode)
 language/expressions/async-arrow-function/early-errors-arrow-await-in-formals.js(default)
 language/expressions/async-arrow-function/early-errors-arrow-await-in-formals.js(strict mode)
-language/expressions/class/elements/fields-duplicate-privatenames.js(default)
-language/expressions/class/elements/fields-duplicate-privatenames.js(strict mode)
 language/expressions/class/elements/fields-literal-name-static-propname-constructor.js(default)
 language/expressions/class/elements/fields-literal-name-static-propname-constructor.js(strict mode)
 language/expressions/class/elements/fields-string-name-static-propname-constructor.js(default)
@@ -412,32 +410,6 @@ language/expressions/class/elements/syntax/early-errors/grammar-private-environm
 language/expressions/class/elements/syntax/early-errors/grammar-private-environment-on-class-heritage.js(strict mode)
 language/expressions/class/elements/syntax/early-errors/grammar-private-field-on-object-destructuring.js(default)
 language/expressions/class/elements/syntax/early-errors/grammar-private-field-on-object-destructuring.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async-gen.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async-gen.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-gen.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-gen.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-field.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-field.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-get.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-get.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-field.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-field.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-get.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-get.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-meth.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-meth.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-set.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-set.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticfield.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticfield.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticmeth.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticmeth.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-field.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-field.js(strict mode)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-set.js(default)
-language/expressions/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-set.js(strict mode)
 language/expressions/class/elements/syntax/early-errors/grammar-privatename-in-computed-property-missing.js(default)
 language/expressions/class/elements/syntax/early-errors/grammar-privatename-in-computed-property-missing.js(strict mode)
 language/expressions/class/elements/syntax/early-errors/invalid-names/field-init-call-expression-bad-reference.js(default)
@@ -1028,8 +1000,6 @@ language/module-code/top-level-await/syntax/if-await-expr-boolean.js(default)
 language/module-code/top-level-await/syntax/if-await-expr-boolean.js(strict mode)
 language/module-code/top-level-await/syntax/try-await-expr.js(default)
 language/module-code/top-level-await/syntax/try-await-expr.js(strict mode)
-language/statements/class/elements/fields-duplicate-privatenames.js(default)
-language/statements/class/elements/fields-duplicate-privatenames.js(strict mode)
 language/statements/class/elements/fields-literal-name-static-propname-constructor.js(default)
 language/statements/class/elements/fields-literal-name-static-propname-constructor.js(strict mode)
 language/statements/class/elements/fields-string-name-static-propname-constructor.js(default)
@@ -1056,32 +1026,6 @@ language/statements/class/elements/syntax/early-errors/grammar-private-environme
 language/statements/class/elements/syntax/early-errors/grammar-private-environment-on-class-heritage.js(strict mode)
 language/statements/class/elements/syntax/early-errors/grammar-private-field-on-object-destructuring.js(default)
 language/statements/class/elements/syntax/early-errors/grammar-private-field-on-object-destructuring.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async-gen.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async-gen.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-async.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-gen.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-gen.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-field.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-field.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-get.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-get-get.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-field.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-field.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-get.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-get.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-meth.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-meth.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-set.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-set.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticfield.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticfield.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticmeth.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-meth-staticmeth.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-field.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-field.js(strict mode)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-set.js(default)
-language/statements/class/elements/syntax/early-errors/grammar-privatemeth-duplicate-set-set.js(strict mode)
 language/statements/class/elements/syntax/early-errors/grammar-privatename-in-computed-property-missing.js(default)
 language/statements/class/elements/syntax/early-errors/grammar-privatename-in-computed-property-missing.js(strict mode)
 language/statements/class/elements/syntax/early-errors/invalid-names/field-init-call-expression-bad-reference.js(default)