Can't do anything with text file contents (file_get_contents) - php

Question

FIXED!
File encoding is UTF-16LE, changed to UTF-8 in PhpStorm and it behaves.
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I'm reading a text file in PHP and want to read and manipulate the contents, but as soon as I touch the read contents of the file in anyway it 'breaks'.
If I read the file then echo it the text is displayed but any other operation with not work.
$contents = file_get_contents($file);
echo $contents; // works
$contents .= 'a longer test' . $contents;
echo $contents;
My ultimate goal is to run some regex’s on the contents before dumping it into a database but I need to be able to work with it first.
If it makes any difference I am using Laravel. I tried File::get($file) but have the same outcome.
EDIT to show output - Unicode issue?
//// first echo
POUR L ’É T U DE DE L ’H IST O IR E ET DE LA LANGUE DU PAYS, LA CONSERVATION DES A N TIQ U ITÉS DE L ’IL E , ET LA PUBLICATION DE DOCUMENTS HISTORIQUES, ETC., ETC. FONDÉE LE 28 JANVIER, 1873. DIXIÈME BULLETIN ANNUEL. : C. LE F E U VRE, IM PR IM E U R -É D IT EU R D E LA SOCIÉTÉ, BERESFORD LIBRARY , ST. -H ÉLIE R . 1885. = Page 1 =
// Second echo
POUR L ’É T U DE DE L ’H IST O IR E ET DE LA LANGUE DU PAYS, LA CONSERVATION DES A N TIQ U ITÉS DE L ’IL E , ET LA PUBLICATION DE DOCUMENTS HISTORIQUES, ETC., ETC. FONDÉE LE 28 JANVIER, 1873. DIXIÈME BULLETIN ANNUEL. : C. LE F E U VRE, IM PR IM E U R -É D IT EU R D E LA SOCIÉTÉ, BERESFORD LIBRARY , ST. -H ÉLIE R . 1885. = Page 1 =⁡潬杮牥琠獥ｴ෾਀ഀ਀匀伀䌀䤀䔀吀䔀  䨀䔀刀匀䤀䄀䤀匀䔀ഀ਀倀伀唀刀  䰀 ᤀ줠 吀 唀 䐀䔀  䐀䔀  䰀 ᤀ䠠 䤀匀吀 伀 䤀刀 䔀  䔀吀  䐀䔀  䰀䄀  䰀䄀一䜀唀䔀  䐀唀  倀䄀夀匀Ⰰഀ਀䰀䄀  䌀伀一匀䔀刀嘀䄀吀䤀伀一  䐀䔀匀  䄀 一 吀䤀儀 唀 䤀吀준匀  䐀䔀  䰀 ᤀ䤠䰀 䔀 Ⰰ  䔀吀  䰀䄀  倀唀䈀䰀䤀䌀䄀吀䤀伀一 ഀ਀䐀䔀  䐀伀䌀唀䴀䔀一吀匀  䠀䤀匀吀伀刀䤀儀唀䔀匀Ⰰ  䔀吀䌀⸀Ⰰ  䔀吀䌀⸀ഀ਀䘀伀一䐀준䔀  䰀䔀  ㈀㠀  䨀䄀一嘀䤀䔀刀Ⰰ  ㄀㠀㜀㌀⸀ഀ਀䐀䤀堀䤀저䴀䔀  䈀唀䰀䰀䔀吀䤀一  䄀一一唀䔀䰀⸀ഀ਀㨀ഀ਀䌀⸀  䰀䔀   䘀 䔀 唀 嘀刀䔀Ⰰ  䤀䴀 倀刀 䤀䴀 䔀 唀 刀 ⴀ준 䐀 䤀吀 䔀唀 刀   䐀 䔀  䰀䄀  匀伀䌀䤀준吀준Ⰰഀ਀䈀䔀刀䔀匀䘀伀刀䐀  䰀䤀䈀刀䄀刀夀 Ⰰ  匀吀⸀ ⴀ䠀 준䰀䤀䔀 刀 ⸀ഀ਀㄀㠀㠀㔀⸀਀ഀ 㴀 倀愀最攀 ㄀ 㴀
If I put the first string into a HEREDOC all works fine, so might be something with the txt file? It's extracted text from an OCRd from am old PDF.
Full code
public function import()
{
// get all the files
$files = File::files('../import');
foreach ($files as $file) {
// load text file contents
$contents = file_get_contents($file);
echo $contents; // as expected
$contents .= 'a longer test' . $contents;
echo $contents; // weird stuff
// test txt file contents inline
$contents2 = <<<EOD
SOCIETE JERSIAISE
POUR L ’É T U DE DE L ’H IST O IR E ET DE LA LANGUE DU PAYS,
LA CONSERVATION DES A N TIQ U ITÉS DE L ’IL E , ET LA PUBLICATION
DE DOCUMENTS HISTORIQUES, ETC., ETC.
FONDÉE LE 28 JANVIER, 1873.
DIXIÈME BULLETIN ANNUEL.
:
C. LE F E U VRE, IM PR IM E U R -É D IT EU R D E LA SOCIÉTÉ,
BERESFORD LIBRARY , ST. -H ÉLIE R .
1885.
= Page 1 =
EOD;
echo $contents2; // works
$contents2 .= 'a longer test' . $contents2;
echo $contents2; // prints as expected
}

Answer 1

FIXED!
File encoding is UTF-16LE, changed to UTF-8 in PhpStorm and it behaves.
Or in code:
foreach ($files as $file) {
// load text file contents
$contents = file_get_contents($file);
// fix encoding
$contents = mb_convert_encoding($contents, 'UTF-8', 'UTF-16');
echo $contents;
.....

Answer 2

$data_to_write = 'test';
$file_handle = fopen($file, 'a');
fwrite($file_handle, $data_to_write);
fclose($file_handle);