Ensure replies to the help message will work

This commit makes some changes and adds some tests to ensure that
valid replies to the gettor help message will contain links.
Non-valid replies should still return the GetTor help message.

gettor/parse/email.py

@@ -13,6 +13,7 @@
 from __future__ import absolute_import
 
 import re
+import io
 import dkim
 import hashlib
 
@@ -117,18 +118,22 @@ class EmailParser(object):
 
     def parse_keywords(self, text, request):
 
-        for word in re.split(r"\s+", text.strip()):
-            for locale in self.locales:
-                if word.lower() == locale.lower():
-                    request["language"] = locale
-                elif (not request["language"]) and (word.lower()[:2] ==
-                        locale.lower()[:2]):
-                    request["language"] = locale
-            if word.lower() in self.platforms:
-                request["command"] = "links"
-                request["platform"] = word.lower()
-            if (not request["command"])  and word.lower() == "help":
-                request["command"] = "help"
+        buf = io.StringIO(text)
+        for line in buf:
+            if len(line.strip()) > 0 and line.strip()[0] == ">":
+                continue
+            for word in re.split(r"\s+", line.strip()):
+                for locale in self.locales:
+                    if word.lower() == locale.lower():
+                        request["language"] = locale
+                    elif (not request["language"]) and (word.lower()[:2] ==
+                            locale.lower()[:2]):
+                        request["language"] = locale
+                if word.lower() in self.platforms:
+                    request["command"] = "links"
+                    request["platform"] = word.lower()
+                if (not request["command"])  and word.lower() == "help":
+                    request["command"] = "help"
         return request
 
     def build_request(self, msg_str, norm_addr):

tests/test_email_service.py

@@ -210,6 +210,47 @@ class EmailServiceTests(unittest.TestCase):
         assert "en-US" in ep.locales
         del ep
 
+    def test_help_reply(self):
+        #Replying to GetTor Help with a valid links request should get you links
+        ep = conftests.EmailParser(self.settings, "gettor@torproject.org")
+        ep.locales = ["en-US", "es-ES", "es-AR", "pt-BR", "fa"]
+        request = ep.parse("From: \"silvia [hiro]\" <hiro@torproject.org>\n"
+                "Subject: Re: [GetTor] Help Email\r\n Reply-To: hiro@torproject.org \nTo:"
+                "gettor@torproject.org\n osx en\n")
+        self.assertEqual(request["command"], "links")
+        self.assertEqual(request["language"], "en-US")
+        self.assertEqual(request["platform"], "osx")
+
+        request = ep.parse("From: \"silvia [hiro]\" <hiro@torproject.org>\n"
+                "Subject: Re: [GetTor] Help Email\r\n Reply-To: hiro@torproject.org \nTo:"
+                "gettor@torproject.org\nlinux fa\n\n"
+                "On 2020-02-10 11:54 a.m., gettor@torproject.org wrote:\n"
+                "> This is how you can request a tor browser bundle link.\n"
+                ">\n"
+                "> Send an email to: gettor@torproject.org\n"
+                ">\n"
+                "> In the body of the email only write: <operating system> <language>.\n"
+                ">\n"
+                "> We only support windows, osx and linux as operating systems.\n"
+                ">\n")
+        self.assertEqual(request["command"], "links")
+        self.assertEqual(request["language"], "fa")
+        self.assertEqual(request["platform"], "linux")
+
+        request = ep.parse("From: \"silvia [hiro]\" <hiro@torproject.org>\n"
+                "Subject: Re: [GetTor] Help Email\r\n Reply-To: hiro@torproject.org \nTo:"
+                "gettor@torproject.org\n"
+                "On 2020-02-10 11:54 a.m., gettor@torproject.org wrote:\n"
+                "> This is how you can request a tor browser bundle link.\n"
+                ">\n"
+                "> Send an email to: gettor@torproject.org\n"
+                ">\n"
+                "> In the body of the email only write: <operating system> <language>.\n"
+                ">\n"
+                "> We only support windows, osx and linux as operating systems.\n"
+                ">\n")
+        self.assertEqual(request["command"], "help")
+
 
 if __name__ == "__main__":
     unittest.main()