I don't know if it's a program error or my settings error. Merge branch lost empty lines and line breaks in the code. Please refer to the following for specific details. This is before the merger.The content at the end of the file is the end of the file, and there are no blank lines at the end of the file:

// read cookie
function getCookie(name) {
    var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)");
    if(arr=document.cookie.match(reg))
        return unescape(arr[2]);
    else
        return null;
}

This is after the merger(Maekdown code block '+' preview not working properly, use '\+' instead '+'):

  // read cookie
  function getCookie(name) {
      var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)");
      if(arr=document.cookie.match(reg))
          return unescape(arr[2]);
      else
          return null;
\+ }function saveLogToFile() {
\+     let receivedMsg = document.getElementById("receivedMsg");
\+     let log = receivedMsg.value;
\+     const blob = new Blob([log], {type: "text/plain;charset=utf-8"});
\+     const url = URL.createObjectURL(blob);
\+     const aTag = document.createElement('a');
\+     aTag.href = url;
\+     aTag.download = "log.txt";
\+     aTag.click();
\+     URL.revokeObjectURL(url);
  }

The correct result should be as follows:

  // read cookie
  function getCookie(name) {
      var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)");
      if(arr=document.cookie.match(reg))
          return unescape(arr[2]);
      else
          return null;
   }

\+  function saveLogToFile() {
\+     let receivedMsg = document.getElementById("receivedMsg");
\+     let log = receivedMsg.value;
\+     const blob = new Blob([log], {type: "text/plain;charset=utf-8"});
\+     const url = URL.createObjectURL(blob);
\+     const aTag = document.createElement('a');
\+     aTag.href = url;
\+     aTag.download = "log.txt";
\+     aTag.click();
\+     URL.revokeObjectURL(url);
\+  }

My file is encoded as "UTF-8" and the line break is "CRLF".

Please refer to the following for specific details.

Can you tell us what version of fossil you're using and on what platform?

This is the first report of this particular problem and no changes have been made to the merge-related code in years, so it would be very useful for debugging this if you can provide us with a copy of the repository and show us which version can reproduce this problem.

Is the line really missing in the merged copy, or is perhaps the diff command showing the line as missing but the line is really there?

I am currently at home, and the repository where the problem occurred is on the company computer. I cannot remember some of the projects clearly.

I am experimenting with using Fossil in a simple web project. If possible, I can also provide you with the entire repository, but it will take at least 10 hours for me to start work, and my time zone is UTC+8.

Platform: Windows 10
Fossil version: 2.22 or 2.23
The command I am using is: fossil merge -- cherrypick [Version]

If possible, I can also provide you with the entire repository, but it will take at least 10 hours for me to start work, and my time zone is UTC+8.

That would be great. There's no hurry.

The command I am using is: fossil merge -- cherrypick Version

When you provide the repo, please be sure to tell us which version you're working from and which one you're cherrypicking.

I'm sorry for being available so late.

https://www.mediafire.com/file/a58n2gg4wpp9qcc/fossil_websocket.zip/file
This is the Fossil repository where I encountered issues.

I merged "trunk[3b14e633fe]" into the ShenTong branch at "ShenTong[e133cc3a8d]" (commit log written incorrectly), and then found that the websocket.js file at the end of the ShenTong branch had an abnormal format.

Operating system: Windows 10 1909

Fossil version: 2.23

Merge command:fossil merge --cherrypick 3b14e633fe

Thanks for providing the repository.

Looking at the progression of the file through the branches, my immediate thought is that the issue is related to the lack of line terminator at end of file (which is sometimes there, sometimes not). That, and the fact that the merge adds a new function at the end of the file.

It's what you said, and I also think it might have something to do with the end-of-file character. I'll try to find the cause of the missing end-of-file character and try to avoid that.

I also think it might have something to do with the end-of-file character. I'll try to find the cause of the missing end-of-file character and try to avoid that.

There shouldn't be an explicit EOF character but there should definitely be an EOL/CRNL at the end of the last line. Without that, lots of tools will behave like fossil did for those inputs.

I managed to reproduce this (with a small difference) on my macOS using trunk. I use standard Unix LF newlines here, not CRLF.

The steps to reproduce:

1. Create a file in trunk without a final newline (10 line function "func1 {\n...\n}")
2. Add a final newline and commit to a new branch X ("func1 {\n...\n}\n")
3. Rename the function in branch X, still with a final newline ("func_xxx {\n...\n}\n"")
4. Switch back to trunk
5. Add a new 5 line function and a final newline with two newlines between the functions ("func1 {\n...\n}\n\nfunc2 {\n...\n}\n")
6. Switch to the X branch
7. Merge in change trunk (with or without --cherrypick)
8. Results is missing one newline between the functions ("func_xxx {\n...\n}\nfunc2 {\n...\n}\n")

In my case, the spacing between the function is now gone (I have one instead of two newlines) where in your case both are gone.

I used the "fossil diff" command to compare the two versions that had merge errors:

fossil diff webSocket.js --from e133cc3a8d --to 3b14e633fe

The comparison results are as follows:

     if(arr=document.cookie.match(reg))
         return unescape(arr[2]);
     else
         return null;
+}
+
+function saveLogToFile() {
+    let receivedMsg = document.getElementById("receivedMsg");
+    let log = receivedMsg.value;
+    const blob = new Blob([log], {type: "text/plain;charset=utf-8"});
+    const url = URL.createObjectURL(blob);
+    const aTag = document.createElement('a');
+    aTag.href = url;
+    aTag.download = "log.txt";
+    aTag.click();
+    URL.revokeObjectURL(url);
 }

That's a good result.

For VSCode, take a look at the following settings:

  "files.insertFinalNewline": true,     // re. "there is no EOL at the end of the file"
  "editor.renderFinalNewline": "dimmed" // re. "I didn't notice the missing EOL"

While I do understand the POSIX take on this (text files and lines thereof) and find it generally a good idea - also in connection with the C standard (A source file that is not empty shall end in a new-line character, which shall not be immediately preceded by a backslash character.) - Windows e.g. not being POSIX-compliant is here less strict and this is pretty bound to happen, so tools should be prepared for this.

This is the cause that leads to a rather unfortunate discrepancy in the file contents, as visible in the two diffs:

fossil diff -i --from e133 --to 3b14 webSocket.js

shows the change as expected, preserving the two newlines, but

fossil diff -i --from e133 --to 6707 webSocket.js

does not.

I'd call this at best an inconsistency, at worst a bug, since content of the file as of check-in 3b14 is not being carried forward on merge.

For VSCode, take a look at the following settings:

Thanks for the instruction.

I'd call this at best an inconsistency, at worst a bug, since content of the file as of check-in 3b14 is not being carried forward on merge.

I agree with you, and it's hard to find errors in this case when there are more files to modify.

As you say, here I used fossil merge --cherrypick by mistake.
I incorrectly assumed that neither the trunk branch nor the ShenTong branch had 'rnrn' at the end of the file, but I just looked at trunk[98398ce8c1] and ShenTong[e133cc3a8d], and I see that 'trunk[98398ce8c1]' does have 'rnrn' at the end of the file (this difference was introduced in trunk[17495e44d8]).
cherrypick's version of trunk[3b14e633fe] changes as follows:

    var arr,reg=new RegExp("(^| )"+name+"=([^;]*)(;|$)");
    if(arr=document.cookie.match(reg))
        return unescape(arr[2]);
    else
        return null;
}

+function saveLogToFile() {
+    let receivedMsg = document.getElementById("receivedMsg");
+    let log = receivedMsg.value;
+    const blob = new Blob([log], {type: "text/plain;charset=utf-8"});
+    const url = URL.createObjectURL(blob);
+    const aTag = document.createElement('a');
+    aTag.href = url;
+    aTag.download = "log.txt";
+    aTag.click();
+    URL.revokeObjectURL(url);
+}

So fossil merge --cherrypick results are as expected.

Sorry, this was is my mistake.

Think you!