notmuch: add strategies for multi-file messages

A single notmuch message can represent multiple files. As a result,
file-based operations like move, copy, and delete can be ambiguous. Add
a new account config option, multi-file-strategy, to tell aerc how to
handle these ambiguous cases. Also add options to relevant commands to
set the multi-file strategy on a per-invocation basis.

If no multi-file strategy is set, refuse to take file-based actions on
multi-file messages. This default behavior is mostly the same as aerc's
previous behavior, but a bit stricter in some cases which previously
tried to be smart about multi-file operations (e.g., move and delete).

Applying multi-file strategies to cross-account copy and move operations
is not implemented. These operations will proceed as they have in the
past -- aerc will copy/move a single file. However, for cross-account
move operations, aerc will refuse to delete multiple files to prevent
data loss as not all of the files are added to the destination account.

See the changes to aerc-notmuch(5) for details on the currently
supported multi-file strategies.

Changelog-added: Tell aerc how to handle file-based operations
 on multi-file notmuch messages with the account config option
 `multi-file-strategy` and the `-m` flag to `:archive`, `:copy`,
 `:delete`, and `:move`.
Signed-off-by: Jason Cox <me@jasoncarloscox.com>
Tested-by: Maarten Aertsen <maarten@nlnetlabs.nl>
Acked-by: Robin Jarry <robin@jarry.cc>

1 files changed, 16 insertions, 7 deletions

diff --git a/doc/aerc.1.scd b/doc/aerc.1.scd
index af1ce31c..3f52fbac 100644
--- a/doc/aerc.1.scd
+++ b/doc/aerc.1.scd
@@ -265,7 +265,7 @@ These commands work in any context.
 These commands are valid in any context that has a selected message (e.g. the
 message list, the message in the message viewer, etc).
 
-*:archive* _<scheme>_
+*:archive* [*-m* _<strategy>_] _<scheme>_
 	Moves the selected message to the archive. The available schemes are:
 
 	_flat_: No special structure, all messages in the archive directory
@@ -274,6 +274,9 @@ message list, the message in the message viewer, etc).
 
 	_month_: Messages are stored in folders per year and subfolders per month
 
+	The *-m* option sets the multi-file strategy. See *aerc-notmuch*(5) for more
+	details.
+
 *:accept* [*-e*|*-E*]
 	Accepts an iCalendar meeting invitation.
 
@@ -288,8 +291,8 @@ message list, the message in the message viewer, etc).
 
 	*-E*: Forces *[compose].edit-headers* = _false_ for this message only.
 
-*:copy* [*-p*] [*-a* _<account>_] _<folder>_++
-*:cp* [*-p*] [*-a* _<account>_] _<folder>_
+*:copy* [*-p*] [*-a* _<account>_] [*-m* _<strategy>_] _<folder>_++
+*:cp* [*-p*] [*-a* _<account>_] [*-m* _<strategy>_] _<folder>_
 	Copies the selected message(s) to _<folder>_.
 
 	*-p*: Create _<folder>_ if it does not exist.
@@ -297,6 +300,8 @@ message list, the message in the message viewer, etc).
 	*-a*: Copy to _<folder>_ of _<account>_. If _<folder>_ does
 	not exist, it will be created whether or not *-p* is used.
 
+	*-m*: Set the multi-file strategy. See *aerc-notmuch*(5) for more details.
+
 *:decline* [*-e*|*-E*]
 	Declines an iCalendar meeting invitation.
 
@@ -304,10 +309,12 @@ message list, the message in the message viewer, etc).
 
 	*-E*: Forces *[compose].edit-headers* = _false_ for this message only.
 
-*:delete*++
-*:delete-message*
+*:delete* [*-m* _<strategy>_]++
+*:delete-message* [*-m* _<strategy>_]
 	Deletes the selected message.
 
+	*-m*: Set the multi-file strategy. See *aerc-notmuch*(5) for more details.
+
 *:envelope* [*-h*] [*-s* _<format-specifier>_]
 	Opens the message envelope in a dialog popup.
 
@@ -351,8 +358,8 @@ message list, the message in the message viewer, etc).
 
 	*-E*: Forces *[compose].edit-headers* = _false_ for this message only.
 
-*:move* [*-p*] [*-a* _<account>_] _<folder>_++
-*:mv* [*-p*] [*-a* _<account>_] _<folder>_
+*:move* [*-p*] [*-a* _<account>_] [*-m* _<strategy>_] _<folder>_++
+*:mv* [*-p*] [*-a* _<account>_] [*-m* _<strategy>_] _<folder>_
 	Moves the selected message(s) to _<folder>_.
 
 	*-p*: Create _<folder>_ if it does not exist.
@@ -360,6 +367,8 @@ message list, the message in the message viewer, etc).
 	*-a*: Move to _<folder>_ of _<account>_. If _<folder>_ does
 	not exist, it will be created whether or not *-p* is used.
 
+	*-m*: Set the multi-file strategy. See *aerc-notmuch*(5) for more details.
+
 *:patch* _<args ...>_
 	Patch management sub-commands. See *aerc-patch*(7) for more details.