feat(keybindings): add cj/custom-keymap registration API

Phase 3 of the load-graph project. cj/register-prefix-map and cj/register-command bind a prefix map or command under the C-; prefix and register the which-key label once which-key loads. Feature modules will route their registration through these instead of mutating cj/custom-keymap directly, so keybindings.el stays the sole owner of the prefix and modules stop assuming the keymap already exists at load.

Adds test-init-keymap-registration.el covering prefix-map and command resolution, the optional label, and invalid-key rejection. No modules are migrated yet; that follows in batches.

1 files changed, 45 insertions, 0 deletions

diff --git a/tests/test-init-keymap-registration.el b/tests/test-init-keymap-registration.el
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+++ b/tests/test-init-keymap-registration.el
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+;;; test-init-keymap-registration.el --- Keymap registration API contract -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Phase 3 of the load-graph project introduces a small registration API in
+;; keybindings.el so feature modules stop mutating `cj/custom-keymap' directly.
+;; These tests pin the contract: a registered prefix map or command resolves
+;; from `cj/custom-keymap', the which-key label is optional, and an invalid key
+;; signals.  Each test rebinds `cj/custom-keymap' to a fresh keymap so the real
+;; global prefix is never polluted.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'keybindings)
+
+(ert-deftest test-init-keymap-registration-prefix-map-resolves ()
+  "Normal: a prefix map registered under KEY resolves from cj/custom-keymap."
+  (let ((cj/custom-keymap (make-sparse-keymap))
+        (sub (make-sparse-keymap)))
+    (cj/register-prefix-map "a" sub "alpha")
+    (should (eq sub (keymap-lookup cj/custom-keymap "a")))))
+
+(ert-deftest test-init-keymap-registration-command-resolves ()
+  "Normal: a command registered under KEY resolves from cj/custom-keymap."
+  (let ((cj/custom-keymap (make-sparse-keymap)))
+    (cj/register-command "b" #'ignore "beta")
+    (should (eq #'ignore (keymap-lookup cj/custom-keymap "b")))))
+
+(ert-deftest test-init-keymap-registration-label-optional ()
+  "Boundary: registration without a LABEL still binds the key."
+  (let ((cj/custom-keymap (make-sparse-keymap))
+        (sub (make-sparse-keymap)))
+    (cj/register-prefix-map "c" sub)
+    (should (eq sub (keymap-lookup cj/custom-keymap "c")))))
+
+(ert-deftest test-init-keymap-registration-invalid-key-signals ()
+  "Error: a non-string key is rejected by the underlying keymap-set."
+  (let ((cj/custom-keymap (make-sparse-keymap)))
+    (should-error (cj/register-prefix-map 42 (make-sparse-keymap)))))
+
+(provide 'test-init-keymap-registration)
+;;; test-init-keymap-registration.el ends here