TypeScript Version: nightly (2.6.0-dev.20170927)

See the fourslash test codeFixChangeExtendsToImplementsAbstractModifier.ts and codeFixChangeExtendsToImplementsWithDecorator.ts.

Code

abstract class A extends I1 implements I2 { }

Expected behavior:

abstract class A implements I1, I2 { }

Actual behavior:

abstract class A implements I1 , I2 { }