health-check: Add check for newline at ends of files

Fixes a couple of files that were missing them.

BUG=b:242605601
TEST=./tools/health-check --fix

Change-Id: I620d6a939cb824e014002152584aacfc5dfdf7e8
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/3835648
Reviewed-by: Daniel Verkamp <dverkamp@chromium.org>
Tested-by: Dennis Kempin <denniskempin@google.com>
Commit-Queue: Dennis Kempin <denniskempin@google.com>

tools/health-check

@@ -3,6 +3,7 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import os
 import re
 import sys
 from datetime import datetime
@@ -10,15 +11,7 @@ from pathlib import Path
 from typing import List
 
 from impl.check_code_hygiene import has_crlf_line_endings
-from impl.common import (
-    CROSVM_ROOT,
-    argh,
-    chdir,
-    cmd,
-    cwd_context,
-    parallel,
-    run_main,
-)
+from impl.common import CROSVM_ROOT, argh, chdir, cmd, cwd_context, parallel, run_main
 from impl.health_check import Check, CheckContext, run_checks
 
 
@@ -146,6 +139,24 @@ def check_infra_tests(context: CheckContext):
     recipes("test run --py3-only").fg(quiet=True)
 
 
+def check_file_ends_with_newline(context: CheckContext):
+    "Checks if files end with a newline."
+    for file_path in context.modified_files:
+        with file_path.open("rb") as file:
+            # Skip empty files
+            file.seek(0, os.SEEK_END)
+            if file.tell() == 0:
+                continue
+            # Check last byte of the file
+            file.seek(-1, os.SEEK_END)
+            file_end = file.read(1)
+            if file_end.decode("utf-8") != "\n":
+                if context.fix:
+                    file_path.write_text(file_path.read_text() + "\n")
+                else:
+                    raise Exception(f"File does not end with a newline {file_path}")
+
+
 # List of all checks and on which files they should run.
 CHECKS: List[Check] = [
     Check(
@@ -202,6 +213,10 @@ CHECKS: List[Check] = [
         ],
         can_fix=True,
     ),
+    Check(
+        check_file_ends_with_newline,
+        exclude=["**.h264", "**.vp8", "**.bin", "**.png", "**.min.js", "infra/**.json"],
+    ),
     Check(check_crlf_line_endings),
 ]
 

tools/impl/common.py

@@ -573,7 +573,10 @@ def add_verbose_args(parser: argparse.ArgumentParser):
 
 
 def all_tracked_files():
-    return (Path(f) for f in cmd("git ls-files").lines())
+    for line in cmd("git ls-files").lines():
+        file = Path(line)
+        if file.is_file():
+            yield file
 
 
 def find_source_files(extension: str, ignore: List[str] = []):

tools/impl/health_check.py

@@ -69,7 +69,9 @@ def list_file_diff():
     if upstream:
         for line in git("diff --name-status", upstream).lines():
             parts = line.split("\t", 1)
-            yield (parts[0].strip(), Path(parts[1].strip()))
+            file = Path(parts[1].strip())
+            if file.is_file():
+                yield (parts[0].strip(), file)
     else:
         print("WARNING: Not tracking a branch. Checking all files.")
         for file in all_tracked_files():