line-at-eof: add a formatter which adds newlines to the end of files

src/CMakeLists.txt

@@ -56,6 +56,7 @@ function (install_formatter name)
 endfunction ()
 
 add_subdirectory(c)
+add_subdirectory(generic)
 add_subdirectory(python)
 add_subdirectory(rust)
 

src/generic/CMakeLists.txt

+add_formatter(line-at-eof reformat)

src/generic/format.line-at-eof

+#!/bin/sh
+# This formatter ensures that non-empty files have a newline at the end of the
+# file.
+
+set -e
+
+readonly path="$1"
+shift
+
+if ! [ -f "$path" ]; then
+    echo >&2 'error: could not find file to format: '"$path"
+    exit 4
+fi
+
+exec sed -i -e '$a\' "$path"

src/generic/line-at-eof.yaml.in

+formatter_line-at-eof:
+    kind: "line-at-eof"
+    script: "@CMAKE_INSTALL_PREFIX@/bin/format.line-at-eof"

test/line-at-eof/CMakeLists.txt

+add_formatter_test(line-at-eof missing-eof missing-eof format)
+add_formatter_test(line-at-eof have-eof have-eof pass)
+add_formatter_test(line-at-eof empty empty pass)

test/line-at-eof/have-eof/have-eof

+This line has an EOL at the EOL.

test/line-at-eof/have-eof/have-eof.clean

+This line has an EOL at the EOL.

test/line-at-eof/have-eof/have-eof.expect

+This line has an EOL at the EOL.

test/line-at-eof/missing-eof/missing-eof

+This line is missing an EOL at the EOL.
\ No newline at end of file

test/line-at-eof/missing-eof/missing-eof.clean

+This line is missing an EOL at the EOL.
\ No newline at end of file

test/line-at-eof/missing-eof/missing-eof.expect

+This line is missing an EOL at the EOL.