test(gui): doom config boot parity green; spacemacs GUI stays open

The empty-scratch wall was two bugs stacked, neither a rendering bug:

1. The probe fixture had unbalanced parens after string surgery — GNU
   failed to load it (end-of-file), the tick never armed, and every
   harness run timed out from a probe that was never running.  The
   needle redesign (scan *Messages* for the framework's finish line,
   since minimal doom sets initial-scratch-message nil and ships no
   dashboard without a DOOMDIR) rides along in the rewritten fixture.
2. With the fixture loading, doom GUI parity passes in 15s — GNU and
   Neomacs boot the sealed doom fixture on isolated Xvfb, identical
   frame/buffer/visible-text state.

Spacemacs GUI remains open, GNU-side only: in the harness GNU never
opens its X connection (no socket fd; gmain/gdbus idle; pango parked)
while the doom sibling passes on identical env and TUI spacemacs parity
is green — a spacemacs-specific pre-display block to chase separately.

Author: eval-exec

crates/neomacs-gui-tests/fixtures/config-env-boot.el

@@ -2,9 +2,8 @@
 ;;
 ;; Shared by the Doom and Spacemacs GUI comparisons: after the config
 ;; framework settles, dump the selected window's visible text and frame
-;; geometry to the artifacts the harness compares.  Which buffer to wait
-;; for is passed in NEOMACS_GUI_CONFIG_HOME_NEEDLE (a string that must
-;; appear in the buffer name or its contents).
+;; geometry to the artifacts the harness compares.  Which string to wait
+;; for is passed in NEOMACS_GUI_CONFIG_HOME_NEEDLE.
 
 (require 'cl-lib)
 
@@ -18,30 +17,44 @@
          (visible (buffer-substring-no-properties
                    (window-start) (window-end nil t)))
          (payload
-          (format "{\"frame\":{\"cols\":%d,\"rows\":%d,\"pixel\":\"%dx%d\"},\
-\"buffer\":\"%s\",\"text\":%S}"
+          (format "{\"frame\":{\"cols\":%d,\"rows\":%d,\"pixel\":\"%dx%d\"},\"buffer\":\"%s\",\"text\":%S}"
                   (frame-width) (frame-height)
                   (frame-pixel-width) (frame-pixel-height)
                   (buffer-name buf) visible)))
     (when path
       (let ((coding-system-for-write 'utf-8))
         (with-temp-file path (insert payload))))))
 
+(defun neomacs-config-boot--finished-p (needle)
+  (or
+   ;; Some visible window names or shows the needle.
+   (cl-some
+    (lambda (window)
+      (or (string-match-p needle (buffer-name (window-buffer window)))
+          (cl-some (lambda (row)
+                     (and row (string-match-p needle row)))
+                   (split-string
+                    (buffer-substring-no-properties
+                     (window-start window) (window-end window t))
+                    "\n"))))
+    (window-list))
+   ;; A config framework may legitimately leave every window empty (the
+   ;; minimal doom fixture sets initial-scratch-message nil and ships no
+   ;; dashboard without a DOOMDIR); its finish line in *Messages* is
+   ;; then the only observable startup signal.  Verified on both editors:
+   ;; ISM=nil, scratch empty, "Doom loaded ..." in *Messages*.
+   (and (get-buffer "*Messages*")
+        (string-match-p
+         needle
+         (with-current-buffer "*Messages*"
+           (buffer-substring-no-properties (point-min) (point-max)))))))
+
 (defvar neomacs-config-boot--deadline nil)
 
 (defun neomacs-config-boot--tick ()
   (let ((needle (or (getenv "NEOMACS_GUI_CONFIG_HOME_NEEDLE") "SPC")))
     (cond
-     ((cl-some
-       (lambda (window)
-         (or (string-match-p needle (buffer-name (window-buffer window)))
-             (cl-some (lambda (row)
-                        (and row (string-match-p needle row)))
-                      (split-string
-                       (buffer-substring-no-properties
-                        (window-start window) (window-end window t))
-                       "\n"))))
-       (window-list))
+     ((neomacs-config-boot--finished-p needle)
       ;; Settle one more idle slice so deferred repaints land, then dump.
       (run-at-time
        2 nil
@@ -63,6 +76,5 @@
       (message "config boot timed out waiting for %S" needle)
       (let (kill-emacs-hook) (kill-emacs 1))))))
 
-(setq neomacs-config-boot--deadline
-      (time-add nil 240))
+(setq neomacs-config-boot--deadline (time-add nil 240))
 (run-at-time 3 nil #'neomacs-config-boot--tick)

crates/neomacs-gui-tests/tests/config_env_boot.rs

@@ -141,21 +141,10 @@ fn compare_config_boot(env: &dyn neomacs_infra::config_env::ConfigEnvironment, n
     );
 }
 
-// Ignored while the probe design catches up with the finding: GNU GUI +
-// the sealed doom fixture boots doom successfully under Xvfb ("Doom
-// loaded 14 packages across 3 modules", pixel capture shows the themed
-// frame) -- but the minimal fixture doom (no DOOMDIR) sets
-// `initial-scratch-message' nil, so the selected window's text is
-// legitimately empty and a window-text needle can never fire.  The
-// comparison needs a doom-GUI-state probe (dashboard buffer, modeline
-// face, or pixel-diff), not window text.  Neomacs on the same fixture
-// shows the vanilla scratch text, which is itself a candidate
-// divergence to settle first.
 #[test]
-#[ignore = "probe design: window-text needle cannot fire on nil scratch; see comment"]
 fn doom_gui_boot_home_buffer_matches_gnu() {
     match neomacs_infra::DoomEnvironment::open() {
-        Some(env) => compare_config_boot(&env, "Doom"),
+        Some(env) => compare_config_boot(&env, "Doom loaded"),
         None => eprintln!(
             "skipping: no sealed Doom fixture; run \
              `cargo run -p xtask -- infra materialize doom`"
@@ -167,8 +156,13 @@ fn doom_gui_boot_home_buffer_matches_gnu() {
 // under Xvfb had not completed within 300s in the last harness run
 // (machine load ~35 during the chase; TUI boots in seconds).  Re-run
 // on a quiet machine before concluding anything about spacemacs GUI.
+// GNU-side only: during the harness run GNU spacemacs never opens its X
+// connection (no socket fd; gmain/gdbus idle; the drawn screen observed
+// on the shared Xvfb is the Neomacs side).  The doom sibling passes on
+// the identical env, so this is spacemacs-specific pre-display blocking,
+// not the harness.  TUI spacemacs parity is green.
 #[test]
-#[ignore = "probe design: see doom sibling; also re-run on quiet machine"]
+#[ignore = "GNU spacemacs GUI blocks before opening X: live investigation"]
 fn spacemacs_gui_boot_home_buffer_matches_gnu() {
     match neomacs_infra::SpacemacsEnvironment::open() {
         Some(env) => compare_config_boot(&env, "Find File"),