Bug: Broken Paste logic

[CookedMelon]

Using this extension causes issues with the copy function in VS Code.

Step to Reproduce:

Create a file like test.java, the content is:

class test {
    private String function () {
        String a = "555\n555";
        a = "ggg";
        return a;
    }
}

Scenario A (Selection Paste): Use the mouse to select the \n characters (inside the double quotes), copy them, and attempt to paste them.

Scenario B (Line Copy/Paste): Place the cursor anywhere inside the double quotes (on the line String a = "\n";) without selecting any text. Use the VS Code shortcut Ctrl + C then Ctrl + V (intended to duplicate the entire line).

Expected Behavior:

Scenario A

Before Paste

After Paste

Scenario B

Before Paste

After Paste

Actual Behavior:

Scenario A

Scenario B

If I place the cursor inside the double quotes

I press ctrl c & ctrl v

[fbricon]

The paste logic mostly does what it's supposed to do: escape the content before pasting it into a Java String (see #1249). So it will literally escape all new lines from the clipboard to insert into a compilable java String.
What you're expecting is raw pasting, you can choose by either Ctrl+Shift+P, or selecting "Insert Plain Text"

you can also disable Java smart pasting entirely with this setting:

"[java]": {
        "editor.pasteAs.enabled": false
}

Now admittedly, at least one thing is not working as expected:

• cursor anywhere on the a = "ggg"; line, then Ctrl+C then Ctrl+Shift+P (Insert plain text) inside the quotes doesn't just duplicate the line, but pastes the whole content into the existing line.

[fbricon]

@CookedMelon the proposed changes in #4306 should fix the duplicate line problem.

Smart pasting could be improved so that pasting \n inside "555\n555" can turn into "555\n\\n555" (as in Eclipse), instead of aggressively adding a new line

String a = "555\n\\n" + //
						"555";

But that needs to happen in https://github.com/eclipse-jdtls/eclipse.jdt.ls/blob/main/org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/handlers/PasteEventHandler.java#L279