[PATCH v2 16/21] cli/new, insert, reindex: change index.decrypt to "auto" by default

[Daniel Kahn Gillmor <dkg@fifthhorseman.net>]

The new "auto" decryption policy is not only good for "notmuch show"
and "notmuch reindex".  It's also useful for indexing messages --
there's no good reason to not try to go ahead and index the cleartext
of a message that we have a stashed session key for.

This change updates the defaults and tunes the test suite to make sure
that they have taken effect.
---
 doc/man1/notmuch-config.rst   | 2 +-
 lib/indexopts.c               | 8 +++++---
 test/T357-index-decryption.sh | 4 ++--
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/doc/man1/notmuch-config.rst b/doc/man1/notmuch-config.rst
index 4835f897..1a9e08a3 100644
--- a/doc/man1/notmuch-config.rst
+++ b/doc/man1/notmuch-config.rst
@@ -154,7 +154,7 @@ The available configuration items are described below.
         DO NOT USE ``index.decrypt=true`` without considering the
         security of your index.
 
-        Default: ``false``.
+        Default: ``auto``.
 
     **built_with.<name>**
 
diff --git a/lib/indexopts.c b/lib/indexopts.c
index a04d1c1c..26a31e89 100644
--- a/lib/indexopts.c
+++ b/lib/indexopts.c
@@ -26,7 +26,7 @@ notmuch_database_get_default_indexopts (notmuch_database_t *db)
     notmuch_indexopts_t *ret = talloc_zero (db, notmuch_indexopts_t);
     if (!ret)
 	return ret;
-    ret->crypto.decrypt = NOTMUCH_DECRYPT_FALSE;
+    ret->crypto.decrypt = NOTMUCH_DECRYPT_AUTO;
 
     char * decrypt_policy;
     notmuch_status_t err = notmuch_database_get_config (db, "index.decrypt", &decrypt_policy);
@@ -38,8 +38,10 @@ notmuch_database_get_default_indexopts (notmuch_database_t *db)
 	    (!(strcasecmp(decrypt_policy, "yes"))) ||
 	    (!(strcasecmp(decrypt_policy, "1"))))
 	    notmuch_indexopts_set_decrypt_policy (ret, NOTMUCH_DECRYPT_TRUE);
-	else if (!strcasecmp(decrypt_policy, "auto"))
-	    notmuch_indexopts_set_decrypt_policy (ret, NOTMUCH_DECRYPT_AUTO);
+	else if ((!(strcasecmp(decrypt_policy, "false"))) ||
+		 (!(strcasecmp(decrypt_policy, "no"))) ||
+		 (!(strcasecmp(decrypt_policy, "0"))))
+	    notmuch_indexopts_set_decrypt_policy (ret, NOTMUCH_DECRYPT_FALSE);
     }
 
     free (decrypt_policy);
diff --git a/test/T357-index-decryption.sh b/test/T357-index-decryption.sh
index 3157fd8c..b2717a7a 100755
--- a/test/T357-index-decryption.sh
+++ b/test/T357-index-decryption.sh
@@ -142,7 +142,7 @@ test_expect_equal \
 
 # ensure no session keys are present:
 test_begin_subtest 'reindex using only session keys'
-test_expect_success 'notmuch reindex --decrypt=auto tag:encrypted and property:index.decryption=success'
+test_expect_success 'notmuch reindex tag:encrypted and property:index.decryption=success'
 test_begin_subtest "reindexed encrypted messages, decrypting only with session keys"
 output=$(notmuch search wumpus)
 expected=''
@@ -190,7 +190,7 @@ notmuch restore <<EOF
 #notmuch-dump batch-tag:3 config,properties,tags
 #= simple-encrypted@crypto.notmuchmail.org session-key=9%3AFC09987F5F927CC0CC0EE80A96E4C5BBF4A499818FB591207705DFDDD6112CF9
 EOF
-notmuch reindex --decrypt=auto id:simple-encrypted@crypto.notmuchmail.org
+notmuch reindex id:simple-encrypted@crypto.notmuchmail.org
 output=$(notmuch search sekrit)
 expected='thread:0000000000000001   2016-12-22 [1/1] Daniel Kahn Gillmor; encrypted message (encrypted inbox unread)'
 test_expect_equal \
-- 
2.15.0