fix(workspace): make finding in directory work with embark

The function called by embark for `project-find-file` always takes the
project root. This is why `wal-find-in-here` now sets a variable that
when present makes that function return the sub-directory instead.

lib/wal-workspace.org

@@ -94,13 +94,23 @@ possible through =C-x 4 p o= which is a bit cumbersome).
 
  (user-error "Project '%s' has no parent project (controlled by `wal-project-parent-project')" name))))
 
+(defvar wal-project-find--directory nil)
+
+(defun wal-project-find-relative-path-instead (_type target)
+ "Find TARGET in a sub-directory.
+
+This is used by `wal-project-find-in-here'."
+ (when wal-project-find--directory
+ (cons 'file (expand-file-name target wal-project-find--directory))))
+
 (defun wal-project-find-in-here (&optional include-all)
  "Find a project file in the current directory.
 
 If INCLUDE-ALL is t, don't ignore otherwise ignored fils."
  (interactive "P")
 
- (when-let ((project (project-current nil)))
+ (when-let ((project (project-current nil))
+ (wal-project-find--directory default-directory))
 
  (project-find-file-in nil (list default-directory) project include-all)))
 
@@ -187,6 +197,10 @@ Root markers (how projects are found) and =vc= ignores are extended.
  ;; Allow setting custom names.
  (put 'project-vc-name 'safe-local-variable #'stringp)
 
+ (advice-add
+ 'embark--project-file-full-path :before-until
+ #'wal-project-find-relative-path-instead)
+
  :custom
  (project-vc-extra-root-markers '("pom.xml"
  "package.json"
@@ -222,6 +236,9 @@ Root markers (how projects are found) and =vc= ignores are extended.
  ("M-h" . wal-project-find-file-other-window)))
 #+END_SRC
 
+#+RESULTS:
+: wal-project-find-file-other-window
+
 * Footer
 :PROPERTIES:
 :VISIBILITY: folded

test/wal-workspace-test.el

@@ -117,6 +117,15 @@
 
  (should (equal (wal-project-local-value 'major-mode) 'text-mode)))))
 
+(ert-deftest wal-project-find-relative-path-instead ()
+ :tags '(workspace)
+
+ (should-not (wal-project-find-relative-path-instead nil "test.el"))
+
+ (let ((wal-project-find--directory "/tmp/one"))
+
+ (should (string= "/tmp/one/test.el" (cdr (wal-project-find-relative-path-instead nil "test.el"))))))
+
 (ert-deftest wal-project-find-in-here ()
  :tags '(workspace user-facing)