GODT-876 Set default from if empty for importing draft

internal/transfer/provider_pmapi_target.go

@@ -118,12 +118,20 @@ func (p *PMAPIProvider) transferDraft(rules transferRules, progress *Progress, m
 	progress.messageImported(msg.ID, importedID, err)
 }
 
-func (p *PMAPIProvider) importDraft(msg Message, globalMailbox *Mailbox) (string, error) {
+func (p *PMAPIProvider) importDraft(msg Message, globalMailbox *Mailbox) (string, error) { //nolint[funlen]
 	message, attachmentReaders, err := p.parseMessage(msg)
 	if err != nil {
 		return "", errors.Wrap(err, "failed to parse message")
 	}
 
+	if message.Sender == nil {
+		mainAddress := p.client().Addresses().Main()
+		message.Sender = &mail.Address{
+			Name:    mainAddress.DisplayName,
+			Address: mainAddress.Email,
+		}
+	}
+
 	// Trying to encrypt an encrypted draft will return an error;
 	// users are forbidden to import messages encrypted with foreign keys to drafts.
 	if message.IsEncrypted() {

test/features/ie/transfer/import_draft.feature

@@ -0,0 +1,24 @@
+Feature: Import from EML files
+  Background:
+    Given there is connected user "user"
+
+  Scenario: Import draft without from fallbacks to primary address
+    Given there is EML file "Drafts/one.eml"
+      """
+      Subject: no from yet
+      To: Internal Bridge <test@protonmail.com>
+      Received: by 2002:0:0:0:0:0:0:0 with SMTP id 0123456789abcdef; Wed, 30 Dec 2020 01:23:45 0000
+
+      hello
+
+      """
+    When user "user" imports local files with rules
+      | source | target |
+      | Drafts | Drafts |
+    Then progress result is "OK"
+    And transfer exported 1 messages
+    And transfer imported 1 messages
+    And transfer failed for 0 messages
+    And API mailbox "Drafts" for "user" has messages
+      | from          | to                  | subject     |
+      | [userAddress] | test@protonmail.com | no from yet |