bug: Emac's narrow-to-defun narrows to the next function when "#if defined" present

[wojnilowicz]

Did you check existing issues?

• I have read all the tree-sitter docs if it relates to using the parser
• I have searched the existing issues of tree-sitter-cpp

Tree-Sitter CLI Version, if relevant (output of tree-sitter --version)

No response

Describe the bug

I'm using Emacs 30.2 and its narrow-to-defun function, which acts faulty i.e. it narrows the next function instead of the function that I'm currently in.

I tracked this issue down to the presence of "#if defined(A)" as shown in the example code below. If:

1. it's not there
2. it's replaced with "#ifdef(A)"
3. I try to narrow on the line above "#if defined(A)"
4. I use c++-mode instead of c++-ts-mode
5. I use c-ts-mode instead of c++-ts-mode
   then everything works as expected.

Additional information:

1. tree-sitter-cpp 0.23.4
2. Fedora 44

Steps To Reproduce/Bad Parse Tree

Steps to reproduce the issue:

1. Open Emacs
2. Load the file below

void functionThatShouldBeNarrowed() {
  int narrowingOnThisLineNarrowsThisFunction; // Press "C-x n d" on this line.
#if defined(A) // Changing this line to "#ifdef(A)" makes the bug disappear.
#endif
  int narrowingOnThisLineNarrowsTheNextFunction; // Press "C-x n d" on this line.
}

void functionThatGetsNarrowed() {}

3. Press M-x and then choose c++-ts-mode
4. Place the cursor on the line with "int narrowingOnThisLineNarrowsTheNextFunction"
5. Press "C-x n d" to launch narrow-to-defun

Behavior:
The function "void functionThatGetsNarrowed()" gets narrowed.

Expected Behavior/Parse Tree

Expected behavior:
The function "void functionThatShouldBeNarrowed()" should be narrowed.

Repro

// Example code that causes the issue
++
void functionThatShouldBeNarrowed() {
  int narrowingOnThisLineNarrowsThisFunction; // Press "C-x n d" on this line.
#if defined(A) // Changing this line to "#ifdef(A)" makes the bug disappear.
#endif
  int narrowingOnThisLineNarrowsTheNextFunction; // Press "C-x n d" on this line.
}

void functionThatGetsNarrowed() {}