From 4989cb0f4604c3e789482cff26f1e2cfaeda328d Mon Sep 17 00:00:00 2001
From: devorun <devran.an12@gmail.com>
Date: Thu, 13 Aug 2026 21:35:48 +0300
Subject: [PATCH] fix(arcup): accept checksum files without a trailing newline

verify_checksum_file used `if ! read -r ... < file` to detect an empty
checksum file, but `read` returns non-zero when the final line has no
trailing newline even though it still populates the variables. A valid
`.sha256` file whose last line lacks a trailing newline was therefore
rejected as "Checksum file is empty", aborting an otherwise-good install.

Check the parsed hash instead of read's exit status, and add a regression
test for the no-trailing-newline case. Bump the installer version per the
in-file convention.
---
 arcup/arcup         | 9 +++++++--
 arcup/test_arcup.sh | 7 +++++++
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/arcup/arcup b/arcup/arcup
index 3590cd36..c4269b6f 100755
--- a/arcup/arcup
+++ b/arcup/arcup
@@ -6,7 +6,7 @@ set -euo pipefail
 
 # NOTE: if you make modifications to this script, please increment the version number.
 # WARNING: the SemVer pattern: major.minor.patch must be followed as we use it to determine if the script is up to date.
-ARCUP_INSTALLER_VERSION="0.2.0"
+ARCUP_INSTALLER_VERSION="0.2.1"
 
 REPO="${ARC_REPO:-circlefin/arc-node}"
 if [[ -n "${ARC_REPO:-}" ]] && [[ ! "$ARC_REPO" =~ ^[A-Za-z0-9_.-]+/[A-Za-z0-9_.-]+$ ]]; then
@@ -656,7 +656,12 @@ verify_checksum_file() {
     local archive_name="$3"
     local expected_checksum expected_name actual_checksum
 
-    if ! read -r expected_checksum expected_name < "$checksum_path"; then
+    # `read` returns non-zero when the final line has no trailing newline, even
+    # though it still populates the variables. Check the parsed hash rather than
+    # read's exit status so a valid checksum file whose last line lacks a
+    # trailing newline is not rejected as empty.
+    read -r expected_checksum expected_name < "$checksum_path" || true
+    if [[ -z "$expected_checksum" ]]; then
         error "Checksum file is empty: $checksum_path"
     fi
 
diff --git a/arcup/test_arcup.sh b/arcup/test_arcup.sh
index 49021191..c62688bc 100755
--- a/arcup/test_arcup.sh
+++ b/arcup/test_arcup.sh
@@ -119,6 +119,13 @@ test_checksum_validation() {
 
     printf '%s  other-asset.tar.gz\n' "$checksum" > "$checksum_file"
     expect_fail "checksum filename mismatch fails" verify_checksum_file "$archive" "$checksum_file" "$archive_name"
+
+    # A checksum file whose final line has no trailing newline is still valid.
+    # `read` returns non-zero at EOF but populates the fields, so it must be
+    # accepted rather than rejected as empty.
+    printf '%s  %s' "$checksum" "$archive_name" > "$checksum_file"
+    verify_checksum_file "$archive" "$checksum_file" "$archive_name"
+    pass "checksum file without trailing newline passes"
 }
 
 test_download_error_lists_assets() {