fix bun path handling and add a test

reflex/utils/path_ops.py

@@ -260,3 +260,19 @@ def find_replace(directory: str | Path, find: str, replace: str):
             text = filepath.read_text(encoding="utf-8")
             text = re.sub(find, replace, text)
             filepath.write_text(text, encoding="utf-8")
+
+
+def samefile(file1: Path, file2: Path) -> bool:
+    """Check if two files are the same.
+
+    Args:
+        file1: The first file.
+        file2: The second file.
+
+    Returns:
+        Whether the files are the same. If either file does not exist, returns False.
+    """
+    if file1.exists() and file2.exists():
+        return file1.samefile(file2)
+
+    return False

reflex/utils/prerequisites.py

@@ -1293,7 +1293,13 @@ def validate_bun():
     """
     bun_path = path_ops.get_bun_path()
 
-    if bun_path and not bun_path.samefile(constants.Bun.DEFAULT_PATH):
+    if bun_path is None:
+        console.error(
+            "Could not find bun. Make sure you have bun installed or run `reflex init` to install it."
+        )
+        raise typer.Exit(1)
+
+    if not path_ops.samefile(bun_path, constants.Bun.DEFAULT_PATH):
         console.info(f"Using custom Bun path: {bun_path}")
         bun_version = get_bun_version()
         if not bun_version:

tests/units/utils/test_utils.py

@@ -115,6 +115,17 @@ def test_typehint_issubclass(subclass, superclass, expected):
     assert types.typehint_issubclass(subclass, superclass) == expected
 
 
+def test_validate_none_bun_path(mocker):
+    """Test that an error is thrown when a bun path is not specified.
+
+    Args:
+        mocker: Pytest mocker object.
+    """
+    mocker.patch("reflex.utils.path_ops.get_bun_path", return_value=None)
+    with pytest.raises(typer.Exit):
+        prerequisites.validate_bun()
+
+
 def test_validate_invalid_bun_path(mocker):
     """Test that an error is thrown when a custom specified bun path is not valid
     or does not exist.