cli/show: make --decrypt take a keyword.

We also expand tab completion for it, update the emacs bindings, and
update T350, T357, and T450 to match.

Make use of the bool-to-keyword backward-compatibility feature.

completion/notmuch-completion.bash

@@ -517,10 +517,14 @@ _notmuch_show()
 	    COMPREPLY=( $( compgen -W "text json sexp mbox raw" -- "${cur}" ) )
 	    return
 	    ;;
-	--exclude|--body|--decrypt)
+	--exclude|--body)
 	    COMPREPLY=( $( compgen -W "true false" -- "${cur}" ) )
 	    return
 	    ;;
+        --decrypt)
+	    COMPREPLY=( $( compgen -W "true auto false" -- "${cur}" ) )
+	    return
+	    ;;
     esac
 
     ! $split &&

doc/man1/notmuch-show.rst

@@ -115,22 +115,27 @@ Supported options for **show** include
         supported with --format=json and --format=sexp), and the
         multipart/signed part will be replaced by the signed data.
 
-    ``--decrypt``
-        Decrypt any MIME encrypted parts found in the selected content
-        (ie. "multipart/encrypted" parts). Status of the decryption will
-        be reported (currently only supported with --format=json and
-        --format=sexp) and on successful decryption the
-        multipart/encrypted part will be replaced by the decrypted
-        content.
+    ``--decrypt=(false|auto|true)``
+        If ``true``, decrypt any MIME encrypted parts found in the
+        selected content (i.e. "multipart/encrypted" parts). Status of
+        the decryption will be reported (currently only supported
+        with --format=json and --format=sexp) and on successful
+        decryption the multipart/encrypted part will be replaced by
+        the decrypted content.
 
-        If a session key is already known for the message, then it
-        will be decrypted automatically unless the user explicitly
-        sets ``--decrypt=false``.
+        If ``auto``, and a session key is already known for the
+        message, then it will be decrypted, but notmuch will not try
+        to access the user's keys.
 
-        Decryption expects a functioning **gpg-agent(1)** to provide any
-        needed credentials. Without one, the decryption will fail.
+        Use ``false`` to avoid even automatic decryption.
 
-        Implies --verify.
+        Non-automatic decryption expects a functioning
+        **gpg-agent(1)** to provide any needed credentials. Without
+        one, the decryption will fail.
+
+        Note: ``true`` implies --verify.
+
+        Default: ``auto``
 
     ``--exclude=(true|false)``
         Specify whether to omit threads only matching

emacs/notmuch-lib.el

@@ -593,7 +593,7 @@ the given type."
 		       (set-buffer-multibyte nil))
 		     (let ((args `("show" "--format=raw"
 				   ,(format "--part=%s" (plist-get part :id))
-				   ,@(when process-crypto '("--decrypt"))
+				   ,@(when process-crypto '("--decrypt=true"))
 				   ,(notmuch-id-to-query (plist-get msg :id))))
 			   (coding-system-for-read
 			    (if binaryp 'no-conversion

emacs/notmuch-query.el

@@ -32,7 +32,7 @@ is a possibly empty forest of replies.
 "
   (let ((args '("show" "--format=sexp" "--format-version=4")))
     (if notmuch-show-process-crypto
-	(setq args (append args '("--decrypt"))))
+	(setq args (append args '("--decrypt=true"))))
     (setq args (append args search-terms))
     (apply #'notmuch-call-notmuch-sexp args)))
 

notmuch-show.c

@@ -1085,8 +1085,6 @@ notmuch_show_command (notmuch_config_t *config, int argc, char *argv[])
     bool exclude = true;
     bool entire_thread_set = false;
     bool single_message;
-    bool decrypt = false;
-    bool decrypt_set = false;
 
     notmuch_opt_desc_t options[] = {
 	{ .opt_keyword = &format, .name = "format", .keywords =
@@ -1101,7 +1099,12 @@ notmuch_show_command (notmuch_config_t *config, int argc, char *argv[])
 	{ .opt_bool = &params.entire_thread, .name = "entire-thread",
 	  .present = &entire_thread_set },
 	{ .opt_int = &params.part, .name = "part" },
-	{ .opt_bool = &decrypt, .name = "decrypt", .present = &decrypt_set },
+	{ .opt_keyword = (int*)(&params.crypto.decrypt), .name = "decrypt",
+	  .keyword_no_arg_value = "true", .keywords =
+	  (notmuch_keyword_t []){ { "false", NOTMUCH_DECRYPT_FALSE },
+				  { "auto", NOTMUCH_DECRYPT_AUTO },
+				  { "true", NOTMUCH_DECRYPT_NOSTASH },
+				  { 0, 0 } } },
 	{ .opt_bool = &params.crypto.verify, .name = "verify" },
 	{ .opt_bool = &params.output_body, .name = "body" },
 	{ .opt_bool = &params.include_html, .name = "include-html" },
@@ -1115,16 +1118,9 @@ notmuch_show_command (notmuch_config_t *config, int argc, char *argv[])
 
     notmuch_process_shared_options (argv[0]);
 
-    if (decrypt_set) {
-	if (decrypt) {
-	    /* we do not need or want to ask for session keys */
-	    params.crypto.decrypt = NOTMUCH_DECRYPT_NOSTASH;
-	    /* decryption implies verification */
-	    params.crypto.verify = true;
-	} else {
-	    params.crypto.decrypt = NOTMUCH_DECRYPT_FALSE;
-	}
-    }
+    /* explicit decryption implies verification */
+    if (params.crypto.decrypt == NOTMUCH_DECRYPT_NOSTASH)
+	params.crypto.verify = true;
 
     /* specifying a part implies single message display */
     single_message = params.part >= 0;

test/T350-crypto.sh

@@ -223,7 +223,7 @@ output=$(notmuch search mimetype:multipart/encrypted and mimetype:application/pg
 test_expect_equal "$output" "thread:XXX   2000-01-01 [1/1] Notmuch Test Suite; test encrypted message 001 (encrypted inbox)"
 
 test_begin_subtest "decryption, --format=text"
-output=$(notmuch show --format=text --decrypt subject:"test encrypted message 001" \
+output=$(notmuch show --format=text --decrypt=true subject:"test encrypted message 001" \
     | notmuch_show_sanitize_all \
     | sed -e 's|"created": [1234567890]*|"created": 946728000|')
 expected='message{ id:XXXXX depth:0 match:1 excluded:0 filename:XXXXX
@@ -255,7 +255,7 @@ test_expect_equal \
     "$expected"
 
 test_begin_subtest "decryption, --format=json"
-output=$(notmuch show --format=json --decrypt subject:"test encrypted message 001" \
+output=$(notmuch show --format=json --decrypt=true subject:"test encrypted message 001" \
     | notmuch_json_show_sanitize \
     | sed -e 's|"created": [1234567890]*|"created": 946728000|')
 expected='[[[{"id": "XXXXX",
@@ -293,7 +293,7 @@ test_expect_equal_json \
     "$expected"
 
 test_begin_subtest "decryption, --format=json, --part=4"
-output=$(notmuch show --format=json --part=4 --decrypt subject:"test encrypted message 001" \
+output=$(notmuch show --format=json --part=4 --decrypt=true subject:"test encrypted message 001" \
     | notmuch_json_show_sanitize \
     | sed -e 's|"created": [1234567890]*|"created": 946728000|')
 expected='{"id": 4,
@@ -307,13 +307,13 @@ test_begin_subtest "decrypt attachment (--part=5 --format=raw)"
 notmuch show \
     --format=raw \
     --part=5 \
-    --decrypt \
+    --decrypt=true \
     subject:"test encrypted message 001" >OUTPUT
 test_expect_equal_file TESTATTACHMENT OUTPUT
 
 test_begin_subtest "decryption failure with missing key"
 mv "${GNUPGHOME}"{,.bak}
-output=$(notmuch show --format=json --decrypt subject:"test encrypted message 001" \
+output=$(notmuch show --format=json --decrypt=true subject:"test encrypted message 001" \
     | notmuch_json_show_sanitize \
     | sed -e 's|"created": [1234567890]*|"created": 946728000|')
 expected='[[[{"id": "XXXXX",
@@ -351,7 +351,7 @@ test_expect_success \
 
 test_begin_subtest "decryption + signature verification"
 test_subtest_broken_gmime_2
-output=$(notmuch show --format=json --decrypt subject:"test encrypted message 002" \
+output=$(notmuch show --format=json --decrypt=true subject:"test encrypted message 002" \
     | notmuch_json_show_sanitize \
     | sed -e 's|"created": [1234567890]*|"created": 946728000|')
 expected='[[[{"id": "XXXXX",

test/T357-index-decryption.sh

@@ -197,14 +197,14 @@ test_expect_equal \
     "$output" \
     "$expected"
 
-test_begin_subtest "show one of the messages with --decrypt"
-output=$(notmuch show --decrypt thread:0000000000000001 | awk '/^\014part}/{ f=0 }; { if (f) { print $0 } } /^\014part{ ID: 3/{ f=1 }')
+test_begin_subtest "show one of the messages with --decrypt=true"
+output=$(notmuch show --decrypt=true thread:0000000000000001 | awk '/^\014part}/{ f=0 }; { if (f) { print $0 } } /^\014part{ ID: 3/{ f=1 }')
 expected='This is a test encrypted message with a wumpus.'
 test_expect_equal \
     "$output" \
     "$expected"
 
-test_begin_subtest "Ensure that we cannot show the message without --decrypt"
+test_begin_subtest "Ensure that we cannot show the message with --decrypt=auto"
 output=$(notmuch show thread:0000000000000001 | awk '/^\014part}/{ f=0 }; { if (f) { print $0 } } /^\014part{ ID: 3/{ f=1 }')
 expected='Non-text part: application/octet-stream'
 test_expect_equal \

test/T450-emacs-show.sh

@@ -191,7 +191,7 @@ This is an error (see *Notmuch errors* for more details)
 === ERROR ===
 [XXX]
 This is an error
-command: YYY/notmuch_fail show --format\\=sexp --format-version\\=4 --decrypt --exclude\\=false \\' \\* \\'
+command: YYY/notmuch_fail show --format\\=sexp --format-version\\=4 --decrypt\\=true --exclude\\=false \\' \\* \\'
 exit status: 1
 stderr:
 This is an error