google / google/google-java-format

unused import removal leaves extra blank line between package declaration and class Javadoc / declaration

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Description

When `google-java-format` removes an unused import statement located between a `package` declaration and class Javadoc or class declaration, it does not collapse the vertical whitespace in the same formatting pass. As a result, the formatted output contains extra blank lines (two consecutive blank lines instead of one).

Running `google-java-format` a second time on the output collapses the extra blank line as expected. We observed this in generated code, more context here: https://github.com/googleapis/librarian/issues/7146

## Environment
* **`google-java-format` Version:** Tested on `1.25.2` through `1.35.0` (including recent builds).
* **Operating System:** Linux / macOS / Cross-platform

## Minimal Reproducible Example

### Input Code (`TestBug.java`)

```java
package com.example;

import static io.grpc.MethodDescriptor.generateFullMethodName;

/**
* Javadoc for class.
*/
public class TestBug {
}

### Command Executed

google-java-format TestBug.java

## Actual Output (First Pass)

package com.example;

/** Javadoc for class. */
public class TestBug {}

(Notice the two consecutive empty lines between package com.example; and /** Javadoc for class. */.)

## Expected Output

package com.example;

/** Javadoc for class. */
public class TestBug {}

## Additional Context & Workaround

• Second Pass Result: Executing google-java-format a second time on the first pass output (google-java-format TestBug.java | google-java-format -) produces the correct output with a single blank line.

Contributor guide

Open the contributing guide

Research direction

Start by reproducing the issue with the TestBug.java example and the google-java-format command. Trace the formatting pass that removes the unused import and handles vertical whitespace between the package declaration and class Javadoc. Done means the first formatting pass produces one blank line, matching the expected output, without needing a second pass.

Written by the indexing model from the issue text.

Assessment

Tech stack
java
Domain
tooling
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Quiet
Clarity
Mostly clear
Newbie friendliness
62/100

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