quoted-printable: Add q-encoding-encode.

* email/quoted-printable.scm (q-encoding-encode): New function.
* tests/quoted-printable.scm (q-encoding wikipedia example): Rename to
...
(q-encoding wikipedia example: decoding): ... this.
(q-encoding wikipedia example: encoding): New test.

2 files changed, 21 insertions, 6 deletions

diff --git a/email/quoted-printable.scm b/email/quoted-printable.scm
index b6f4c54..11abaff 100644
--- a/email/quoted-printable.scm
+++ b/email/quoted-printable.scm
@@ -24,7 +24,8 @@
   #:use-module (srfi srfi-26)
   #:export (quoted-printable-decode
             quoted-printable-encode
-            q-encoding-decode))
+            q-encoding-decode
+            q-encoding-encode))
 
 ;; TODO: Error out on invalid quoted-printable input
 (define quoted-printable-decode
@@ -89,3 +90,9 @@
     (lambda (c)
       (if (char=? c #\_) #\Space c))
     str)))
+
+(define (q-encoding-encode bv)
+  (string-map
+   (lambda (c)
+     (if (char=? c #\Space) #\_ c))
+   (quoted-printable-encode bv)))
diff --git a/tests/quoted-printable.scm b/tests/quoted-printable.scm
index a0f0369..608a937 100755
--- a/tests/quoted-printable.scm
+++ b/tests/quoted-printable.scm
@@ -49,10 +49,18 @@ abriquent pour te la vendre une =C3=A2me vulgaire.")
                           (string->bytevector decoded-text charset))
                          #\newline))))
 
-(test-equal "q-encoding wikipedia example"
-  (bytevector->string
-   (q-encoding-decode "=A1Hola,_se=F1or!")
-   "ISO-8859-1")
-  "¡Hola, señor!")
+(let ((encoded-text "=A1Hola,_se=F1or!")
+      (decoded-text "¡Hola, señor!")
+      (charset "ISO-8859-1"))
+  (test-equal "q-encoding wikipedia example: decoding"
+    (q-encoding-encode
+     (string->bytevector decoded-text charset))
+    encoded-text)
+
+  (test-equal "q-encoding wikipedia example: encoding"
+    (bytevector->string
+     (q-encoding-decode encoded-text)
+     charset)
+    decoded-text))
 
 (test-end "quoted-printable")