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Removing unused imports leaves extra blank line after package statement, isn't idempotent

Open Allc9001 opened this issue 4 years ago • 1 comments

I have a class that if I format it twice with google java formatter it will produce 2 different results. This is not what I would expect - I would think that you can format a file any number of times and google java formatter should always produce the exact same result. Is my assumption wrong ?

Here is an example:

original class:

$ cat inital_class.java
package com.sun.something;

import com.x;
import com.y;
import com.z;

public class MockedLiveServiceExecutionContext {


}
$

If I then format it I get this:

$ java -jar ./google-java-format-1.9-all-deps.jar --replace inital_class.java
$ cat inital_class.java
package com.sun.something;


public class MockedLiveServiceExecutionContext {}
$ cat inital_class.java | cksum
42955951 79
$

And if I format it again I get this (it's removed an extra space):

$ java -jar ./google-java-format-1.9-all-deps.jar --replace inital_class.java
$ cat inital_class.java
package com.sun.something;

public class MockedLiveServiceExecutionContext {}
$ cat inital_class.java | cksum
2486624596 78
$

Allc9001 avatar Apr 22 '21 14:04 Allc9001

Thanks for finding this. We would agree that any non-idempotence is a bug. Since it at least reaches a fixed point quickly (it's like "idempotence, once removed") it might not be a high-priority fix, but we're glad to keep this open until then.

kevinb9n avatar Jun 14 '21 17:06 kevinb9n