Add IPC config subcommand

This patch adds a new mechanism for changing configuration options
without editing the configuration file, by sending options to running
instances through `alacritty msg`.

Each window will load Alacritty's configuration file by default and then
accept IPC messages for config updates using the `alacritty msg config`
subcommand. By default all windows will be updated, individual windows
can be addressed using `alacritty msg config --window-id
"$ALACRITTY_WINDOW_ID"`.

Each option will replace the config's current value and cannot be reset
until Alacritty is restarted or the option is overwritten with a new
value.

Configuration options are passed in the format `field.subfield=value`,
where `value` is interpreted as yaml.

Closes #472.

1 files changed, 15 insertions, 1 deletions

diff --git a/alacritty_terminal/src/index.rs b/alacritty_terminal/src/index.rs
index e672c752..9464b8d8 100644
--- a/alacritty_terminal/src/index.rs
+++ b/alacritty_terminal/src/index.rs
@@ -7,6 +7,8 @@ use std::ops::{Add, AddAssign, Deref, Sub, SubAssign};
 
 use serde::{Deserialize, Serialize};
 
+use alacritty_config_derive::SerdeReplace;
+
 use crate::grid::Dimensions;
 
 /// The side of a cell.
@@ -222,7 +224,19 @@ impl PartialEq<usize> for Line {
 /// A column.
 ///
 /// Newtype to avoid passing values incorrectly.
-#[derive(Serialize, Deserialize, Debug, Copy, Clone, Eq, PartialEq, Default, Ord, PartialOrd)]
+#[derive(
+    SerdeReplace,
+    Serialize,
+    Deserialize,
+    Debug,
+    Copy,
+    Clone,
+    Eq,
+    PartialEq,
+    Default,
+    Ord,
+    PartialOrd,
+)]
 pub struct Column(pub usize);
 
 impl fmt::Display for Column {