From b3ccd4bb262f4e6d3248b46cede92b90c4a42094 Mon Sep 17 00:00:00 2001
From: MrTipson <mr@tipson.xyz>
Date: Fri, 16 Jan 2026 23:22:26 +0100
Subject: [PATCH] fish: source event handling functions on shell init

Functions that contain event handler switches should be sourced during init, otherwise they become active only after being called manually.
---
 modules/programs/fish.nix                     | 17 ++++++++
 tests/modules/programs/fish/default.nix       |  1 +
 .../modules/programs/fish/source-handlers.nix | 42 +++++++++++++++++++
 3 files changed, 60 insertions(+)
 create mode 100644 tests/modules/programs/fish/source-handlers.nix

diff --git a/modules/programs/fish.nix b/modules/programs/fish.nix
index 57ada99c..0e5176bc 100644
--- a/modules/programs/fish.nix
+++ b/modules/programs/fish.nix
@@ -397,6 +397,20 @@ let
     echo "end"
     echo "setup_hm_session_vars") > $out/${sessionVarsFile}
   '';
+  sourceHandlersStr =
+    let
+      handlerAttrs = [
+        "onJobExit"
+        "onProcessExit"
+        "onVariable"
+        "onSignal"
+        "onEvent"
+      ];
+      isHandler = name: def: isAttrs def && builtins.any (attr: builtins.hasAttr attr def) handlerAttrs;
+      handlerFunctions = lib.filterAttrs isHandler cfg.functions;
+      sourceFunction = name: def: "source ${config.xdg.configHome}/fish/functions/${name}.fish";
+    in
+    builtins.concatStringsSep "\n" (lib.mapAttrsToList sourceFunction handlerFunctions);
 
 in
 {
@@ -726,6 +740,9 @@ in
 
           source ${cfg.sessionVariablesPackage}/${sessionVarsFile}
 
+          # Source handler functions
+          ${sourceHandlersStr}
+
           ${cfg.shellInit}
 
           status is-login; and begin
diff --git a/tests/modules/programs/fish/default.nix b/tests/modules/programs/fish/default.nix
index 1e7353a0..0b562fc1 100644
--- a/tests/modules/programs/fish/default.nix
+++ b/tests/modules/programs/fish/default.nix
@@ -4,6 +4,7 @@
   fish-functions = ./functions.nix;
   fish-completions = ./completions.nix;
   fish-no-functions = ./no-functions.nix;
+  fish-source-handlers = ./source-handlers.nix;
   fish-plugins = ./plugins.nix;
   fish-manpage = ./manpage.nix;
   fish-binds = ./binds.nix;
diff --git a/tests/modules/programs/fish/source-handlers.nix b/tests/modules/programs/fish/source-handlers.nix
new file mode 100644
index 00000000..f9690214
--- /dev/null
+++ b/tests/modules/programs/fish/source-handlers.nix
@@ -0,0 +1,42 @@
+{ ... }:
+{
+  config = {
+    programs.fish = {
+      enable = true;
+
+      functions = {
+        normal-function = "";
+        event-handler = {
+          body = "";
+          onEvent = "test";
+        };
+        variable-handler = {
+          body = "";
+          onVariable = "test";
+        };
+        job-handler = {
+          body = "";
+          onJobExit = "10";
+        };
+        signal-handler = {
+          body = "";
+          onSignal = "10";
+        };
+        process-handler = {
+          body = "";
+          onProcessExit = "10";
+        };
+      };
+    };
+
+    nmt.script = ''
+      assertFileExists home-files/.config/fish/config.fish
+      assertFileContains home-files/.config/fish/config.fish "source /home/hm-user/.config/fish/functions/event-handler.fish"
+      assertFileContains home-files/.config/fish/config.fish "source /home/hm-user/.config/fish/functions/variable-handler.fish"
+      assertFileContains home-files/.config/fish/config.fish "source /home/hm-user/.config/fish/functions/job-handler.fish"
+      assertFileContains home-files/.config/fish/config.fish "source /home/hm-user/.config/fish/functions/signal-handler.fish"
+      assertFileContains home-files/.config/fish/config.fish "source /home/hm-user/.config/fish/functions/process-handler.fish"
+      assertFileNotRegex home-files/.config/fish/config.fish "source /home/hm-user/.config/fish/functions/normal-function.fish"
+    '';
+  };
+}