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, 26 insertions, 1 deletions

diff --git a/extra/completions/alacritty.bash b/extra/completions/alacritty.bash
index 428e9583..5cca6466 100644
--- a/extra/completions/alacritty.bash
+++ b/extra/completions/alacritty.bash
@@ -12,6 +12,9 @@ _alacritty() {
             "$1")
                 cmd="alacritty"
                 ;;
+            config)
+                cmd+="__config"
+                ;;
             create-window)
                 cmd+="__create__window"
                 ;;
@@ -100,7 +103,7 @@ _alacritty() {
             return 0
             ;;
         alacritty__msg)
-            opts="-s -h --socket --help create-window help"
+            opts="-s -h --socket --help create-window config help"
             if [[ ${cur} == -* || ${COMP_CWORD} -eq 2 ]] ; then
                 COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
                 return 0
@@ -121,6 +124,28 @@ _alacritty() {
             COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
             return 0
             ;;
+        alacritty__msg__config)
+            opts="-w -r -h --window-id --reset --help <CONFIG_OPTIONS>..."
+            if [[ ${cur} == -* || ${COMP_CWORD} -eq 3 ]] ; then
+                COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
+                return 0
+            fi
+            case "${prev}" in
+                --window-id)
+                    COMPREPLY=($(compgen -f "${cur}"))
+                    return 0
+                    ;;
+                -w)
+                    COMPREPLY=($(compgen -f "${cur}"))
+                    return 0
+                    ;;
+                *)
+                    COMPREPLY=()
+                    ;;
+            esac
+            COMPREPLY=( $(compgen -W "${opts}" -- "${cur}") )
+            return 0
+            ;;
         alacritty__msg__create__window)
             opts="-e -t -h --working-directory --hold --command --title --class --help"
             if [[ ${cur} == -* || ${COMP_CWORD} -eq 3 ]] ; then