From 6abba493b2988f4df8d799b4dd8aff7d30483b83 Mon Sep 17 00:00:00 2001
From: Emanuele Torre <torreemanuele6@gmail.com>
Date: Sun, 3 Jan 2021 19:31:44 +0100
Subject: [PATCH] Meta: Rewrite the check-newlines-at-eof script in python

The bash version takes around 15 seconds to run; that is way too slow.
This python3 version should take less than one second to run. :^)

Also, the script will now also check .py files and .txt CMake files.
---
 Meta/check-newlines-at-eof.py | 62 +++++++++++++++++++++++++++++++++++
 Meta/check-newlines-at-eof.sh | 42 ------------------------
 Meta/lint-ci.sh               |  2 +-
 3 files changed, 63 insertions(+), 43 deletions(-)
 create mode 100755 Meta/check-newlines-at-eof.py
 delete mode 100755 Meta/check-newlines-at-eof.sh

diff --git a/Meta/check-newlines-at-eof.py b/Meta/check-newlines-at-eof.py
new file mode 100755
index 00000000000..d49f5e88bb6
--- /dev/null
+++ b/Meta/check-newlines-at-eof.py
@@ -0,0 +1,62 @@
+#!/bin/python3
+
+import os
+import subprocess
+import sys
+
+os.chdir(os.path.dirname(__file__) + "/..")
+
+files = subprocess.run(
+    [
+        "git", "ls-files", "--",
+        "*.cpp",
+        "*.h",
+        "*.gml",
+        "*.html",
+        "*.js",
+        "*.css",
+        "*.sh",
+        "*.py",
+        "CMake*.txt",
+        "**/CMake*.txt",
+        ":!:Base",
+        ":!:Kernel/FileSystem/ext2_fs.h",
+        ":!:Libraries/LibC/getopt.cpp",
+        ":!:Libraries/LibCore/puff.h",
+        ":!:Libraries/LibCore/puff.cpp",
+        ":!:Libraries/LibELF/exec_elf.h"
+    ],
+    capture_output=True
+).stdout.decode().strip('\n').split('\n')
+
+no_newline_at_eof_errors = []
+blank_lines_at_eof_errors = []
+
+did_fail = False
+for filename in files:
+    with open(filename, "r") as f:
+        f.seek(0, os.SEEK_END)
+
+        f.seek(f.tell() - 1, os.SEEK_SET)
+        if f.read(1) != '\n':
+            did_fail = True
+            no_newline_at_eof_errors.append(filename)
+            continue
+
+        while True:
+            f.seek(f.tell() - 2, os.SEEK_SET)
+            char = f.read(1)
+            if not char.isspace():
+                break
+            if char == '\n':
+                did_fail = True
+                blank_lines_at_eof_errors.append(filename)
+                break
+
+if no_newline_at_eof_errors:
+    print("Files with no newline at the end:", " ".join(no_newline_at_eof_errors))
+if blank_lines_at_eof_errors:
+    print("Files that have blank lines at the end:", " ".join(blank_lines_at_eof_errors))
+
+if did_fail:
+    sys.exit(1)
diff --git a/Meta/check-newlines-at-eof.sh b/Meta/check-newlines-at-eof.sh
deleted file mode 100755
index 77147e62825..00000000000
--- a/Meta/check-newlines-at-eof.sh
+++ /dev/null
@@ -1,42 +0,0 @@
-#!/bin/bash
-
-script_path=$(cd -P -- "$(dirname -- "$0")" && pwd -P)
-cd "$script_path/.." || exit 1
-
-MISSING_NEWLINE_AT_EOF_ERRORS=()
-MORE_THAN_ONE_NEWLINE_AT_EOF_ERRORS=()
-
-while IFS= read -r f; do
-    [ -s "$f" ] || continue
-
-    if [ "$(tail -n 1 "$f" | wc -l)" != 1 ]; then
-        MISSING_NEWLINE_AT_EOF_ERRORS+=( "$f" )
-    elif [[ "$(tail -n 1 "$f")" =~ ^[[:space:]]*$ ]]; then
-        MORE_THAN_ONE_NEWLINE_AT_EOF_ERRORS+=( "$f" )
-    fi
-done < <(git ls-files -- \
-    '*.cpp' \
-    '*.h' \
-    '*.gml' \
-    '*.html' \
-    '*.js' \
-    '*.css' \
-    '*.sh' \
-    ':!:Base' \
-    ':!:Kernel/FileSystem/ext2_fs.h' \
-    ':!:Libraries/LibC/getopt.cpp' \
-    ':!:Libraries/LibCore/puff.h' \
-    ':!:Libraries/LibCore/puff.cpp' \
-    ':!:Libraries/LibELF/exec_elf.h' \
-)
-
-exit_status=0
-if (( ${#MISSING_NEWLINE_AT_EOF_ERRORS[@]} )); then
-    echo "Files with no newline at the end: ${MISSING_NEWLINE_AT_EOF_ERRORS[*]}"
-    exit_status=1
-fi
-if (( ${#MORE_THAN_ONE_NEWLINE_AT_EOF_ERRORS[@]} )); then
-    echo "Files that have blank lines at the end: ${MORE_THAN_ONE_NEWLINE_AT_EOF_ERRORS[*]}"
-    exit_status=1
-fi
-exit "$exit_status"
diff --git a/Meta/lint-ci.sh b/Meta/lint-ci.sh
index 724bcc0f156..68d379d51ca 100755
--- a/Meta/lint-ci.sh
+++ b/Meta/lint-ci.sh
@@ -16,7 +16,7 @@ set +e
 for cmd in \
         Meta/check-ak-test-files.sh \
         Meta/check-debug-flags.sh \
-        Meta/check-newlines-at-eof.sh \
+        Meta/check-newlines-at-eof.py \
         Meta/check-style.sh \
         Meta/lint-executable-resources.sh \
         Meta/lint-ipc-ids.sh \