diff --git a/test/rfc5322.ml b/test/rfc5322.ml
index 9a72766..cb7889e 100644
--- a/test/rfc5322.ml
+++ b/test/rfc5322.ml
@@ -207,13 +207,13 @@ let parse_content_type x (ty, subty, param_count) =
 (* Check that whitespaces are allowed in content type parameter value (PR#72) *)
 let content_type_test =
   let test =
-    {|From: Nathaniel Borenstein <nsb@thumper.bellcore.com>
-      (=?iso-8859-8?b?7eXs+SDv4SDp7Oj08A==?=)
-To: Greg Vaudreuil <gvaudre@NRI.Reston.VA.US>, Ned Freed
-   <ned@innosoft.com>, Keith Moore <moore@cs.utk.edu>
-Subject: Test of new header generator
-MIME-Version: 1.0
-Content-type: text/plain; wpefjjnqwisj231=" q02eifwe0sn  "; weinfw="qwewqe"
+    {|From: Nathaniel Borenstein <nsb@thumper.bellcore.com>|}^"\r"^{|
+      (=?iso-8859-8?b?7eXs+SDv4SDp7Oj08A==?=)|}^"\r"^{|
+To: Greg Vaudreuil <gvaudre@NRI.Reston.VA.US>, Ned Freed|}^"\r"^{|
+   <ned@innosoft.com>, Keith Moore <moore@cs.utk.edu>|}^"\r"^{|
+Subject: Test of new header generator|}^"\r"^{|
+MIME-Version: 1.0|}^"\r"^{|
+Content-type: text/plain; wpefjjnqwisj231=" q02eifwe0sn  "; weinfw="qwewqe"|}^"\r"^{|
 |}
   in
   let ct =
diff --git a/test/test_hd.ml b/test/test_hd.ml
index 952838e..1263b40 100644
--- a/test/test_hd.ml
+++ b/test/test_hd.ml
@@ -18,10 +18,10 @@ let parsers =
   |> Map.add content_encoding unstructured
 
 let test_000 =
-  {|Date:     26 Aug 76 14:29 EDT
-From:     Jones@Registry.Org
-Bcc:
-
+  {|Date:     26 Aug 76 14:29 EDT|}^"\r"^{|
+From:     Jones@Registry.Org|}^"\r"^{|
+Bcc:|}^"\r"^{|
+|}^"\r"^{|
 |}
 
 module Map = Map.Make (Field_name)
@@ -77,14 +77,14 @@ let test_000 =
   Alcotest.(check (list string)) "Bcc" (Map.find Field_name.bcc fields) [ "" ]
 
 let test_001 =
-  {|From  : John Doe <jdoe@machine(comment).  example>
-To    : Mary Smith
-  
-          <mary@example.net>
-Subject     : Saying Hello
-Date  : Fri, 21 Nov 1997 09(comment):   55  :  06 -0600
-Message-ID  : <1234   @   local(blah)  .machine .example>
-
+  {|From  : John Doe <jdoe@machine(comment).  example>|}^"\r"^{|
+To    : Mary Smith|}^"\r"^{|
+  |}^"\r"^{|
+          <mary@example.net>|}^"\r"^{|
+Subject     : Saying Hello|}^"\r"^{|
+Date  : Fri, 21 Nov 1997 09(comment):   55  :  06 -0600|}^"\r"^{|
+Message-ID  : <1234   @   local(blah)  .machine .example>|}^"\r"^{|
+|}^"\r"^{|
 |}
 
 let test_001 =
diff --git a/test/test_mail.ml b/test/test_mail.ml
index e7c196b..3a1947b 100644
--- a/test/test_mail.ml
+++ b/test/test_mail.ml
@@ -249,18 +249,18 @@ let test2 () =
   | Error _ -> Fmt.invalid_arg "Generate unparsable email"
 
 let example3 =
-  {mrmime|From: romain.calascibetta@x25519.net
-To: romain.calascibetta@din.osau.re
-Content-Type: text/plain; charset=utf-8
-Content-Transfer-Encoding: quoted-printable
-
-J'interdis aux marchands de vanter trop leurs marchandises. Car ils se font=
- vite p=C3=A9dagogues et t'enseignent comme but ce qui n'est par essence qu=
-'un moyen, et te trompant ainsi sur la route =C3=A0 suivre les voil=C3=A0 =
-bient=C3=B4t qui te d=C3=A9gradent, car si leur musique est vulgaire il=
-s te fabriquent pour te la vendre une =C3=A2me vulgaire.            
-   =E2=80=94=E2=80=89Antoine de Saint-Exup=C3=A9ry, Citadelle (1948)
-
+  {mrmime|From: romain.calascibetta@x25519.net|mrmime}^"\r"^{mrmime|
+To: romain.calascibetta@din.osau.re|mrmime}^"\r"^{mrmime|
+Content-Type: text/plain; charset=utf-8|mrmime}^"\r"^{mrmime|
+Content-Transfer-Encoding: quoted-printable|mrmime}^"\r"^{mrmime|
+|mrmime}^"\r"^{mrmime|
+J'interdis aux marchands de vanter trop leurs marchandises. Car ils se font=|mrmime}^"\r"^{mrmime|
+ vite p=C3=A9dagogues et t'enseignent comme but ce qui n'est par essence qu=|mrmime}^"\r"^{mrmime|
+'un moyen, et te trompant ainsi sur la route =C3=A0 suivre les voil=C3=A0 =|mrmime}^"\r"^{mrmime|
+bient=C3=B4t qui te d=C3=A9gradent, car si leur musique est vulgaire il=|mrmime}^"\r"^{mrmime|
+s te fabriquent pour te la vendre une =C3=A2me vulgaire.            |mrmime}^"\r"^{mrmime|
+   =E2=80=94=E2=80=89Antoine de Saint-Exup=C3=A9ry, Citadelle (1948)|mrmime}^"\r"^{mrmime|
+|mrmime}^"\r"^{mrmime|
 |mrmime}
 
 let contents =
@@ -278,9 +278,9 @@ let test3 () =
   | Ok _ -> Fmt.invalid_arg "Invalid structure of the email"
   | Error _ -> Fmt.invalid_arg "Invalid email"
 
-let example4 = {mrmime|Subject: A simple email
-
-Hello World!
+let example4 = {mrmime|Subject: A simple email|mrmime}^"\r"^{mrmime|
+|mrmime}^"\r"^{mrmime|
+Hello World!|mrmime}^"\r"^{mrmime|
 |mrmime}
 
 let test4 () =