Before You File a Bug Report Please Confirm You Have Done The Following...

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have searched for related issues and found none that matched my issue.
• I have read the FAQ and my problem is not listed.

Relevant Package

typescript-estree

Playground Link

https://typescript-eslint.io/play/#ts=5.4.3&fileType=.tsx&code=MYGwhgzhAECiCM0DeBfAUKSNYCZno3CmgA1EBTADwBdyA7AE20VTQHo3pNiS8rbGzaP3pM4eVtxgkAzNACWAWwAOIcovrUhrDlyLSALApVqNdLXERLV6zdgnoppAKzCaooddN3x%2BdpycSADZjGzMLBDcBMVw-NHlzcgAnADMwYHJoAE0Kd0FLPwTaVPTMrL48mNzo%2B3xoXUBeDcABHegAFQALeRgIdoB7AFcQBmgAI0yk8mVepNphkYBPaGUwJIhkgBpoEHkAa0ze6nbkiH8FRJKM7LkvW3NtdF0i5LTLrKMb8M8TW4iHU6eLmVXB8fJERPlYjpOACXmUQuCqqFvHdfKggA&eslintrc=N4KABGBEBOCuA2BTAzpAXGYBfEWg&tsconfig=N4KABGBEDGD2C2AHAlgGwKYCcDyiAuysAdgM6QBcYoEEkJemy0eAcgK6qoDCAFutAGsylBm3TgwAXxCSgA&tokens=false

Repro Code

class E1 {}
class E2 {}

// class X2 extends E1 extends E2 {} // This is reported
interface Y2 extends E1 extends E2 {} // This is NOT reported

ESLint Config

tsconfig

Expected Result

Parser should report internal error TS1172: 'extends' clause already seen. like TS does.

https://www.typescriptlang.org/play/?#code/MYGwhgzhAECiCM0DeBfAUKSNYCZno3CmgA1EBTADwBdyA7AE20VTQHo3pNiS8rbGzaP3pM4eVtxgkAzNACWAWwAOIcovrUhrDlyLSALApVqNdLXERLV6zdgnoppAKzCaooddN3x+dpycSADZjGzMLBDcBMVw-NHlzcgAnADMwYHJoAE0Kd0FLPwTaVPTMrL48mNzo+z9dIuS0jOy5L1tzbXR6xJLmrKM28M8TdoiHfwUeprLXQZ9IkXzYnU4G3rKQxarQ7w7fVCA

Actual Result

No errors are reported.

Additional Info

Since duplicate extends are reported correctly for class, they should be reported for interface too?

I can send a PR if this is acceptable change.

leaysgur@0a6d4db

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