Rollup merge of #125625 - ChrisDenton:line-endings, r=Mark-Simulacrum

Use grep to implement verify-line-endings

Unless I'm missing something (which I might be!) then `verify-line-endings` is easy to implement with `grep` rather than using a bespoke tool with varying availability.

src/ci/scripts/verify-line-endings.sh

@@ -4,21 +4,21 @@
 # We check both in rust-lang/rust and in a submodule to make sure both are
 # accurate. Submodules are checked out significantly later than the main
 # repository in this script, so settings can (and do!) change between then.
-#
-# Linux (and maybe macOS) builders don't currently have dos2unix so just only
-# run this step on Windows.
 
 set -euo pipefail
 IFS=$'\n\t'
 
 source "$(cd "$(dirname "$0")" && pwd)/../shared.sh"
 
-if isWindows; then
-    # print out the git configuration so we can better investigate failures in
-    # the following
-    git config --list --show-origin
-    dos2unix -ih Cargo.lock src/tools/rust-installer/install-template.sh
-    endings=$(dos2unix -ic Cargo.lock src/tools/rust-installer/install-template.sh)
-    # if endings has non-zero length, error out
-    if [ -n "$endings" ]; then exit 1 ; fi
+# print out the git configuration so we can better investigate failures in
+# the following
+git config --list --show-origin
+# -U is necessary on Windows to stop grep automatically converting the line ending
+endings=$(grep -Ul $(printf '\r$') Cargo.lock src/tools/cargo/Cargo.lock) || true
+# if endings has non-zero length, error out
+if [[ -n $endings ]]; then
+    echo "Error: found DOS line endings"
+    # Print the files with DOS line endings
+    echo "$endings"
+    exit 1
 fi