Fix grep hook, replace-regexp on missing files, and corrupt bookmarks

- Pass unique=t to rename-buffer in projectile-grep so subsequent
  greps don't fail with "buffer name in use", which prevented
  projectile-grep-finished-hook from running (#1687)
- Filter nonexistent files from projectile-replace-regexp file list
  to avoid stopping on deleted files (#1456)
- Validate that deserialized known-projects data is a proper list,
  gracefully handling corrupted bookmarks files (#1939)

Author: bbatsov

CHANGELOG.md

@@ -10,6 +10,9 @@
 
 * [#1823](https://github.com/bbatsov/projectile/issues/1823): Update the mode-line via `window-configuration-change-hook` so non-file buffers (e.g. Magit) display the correct project info.
 * [#1886](https://github.com/bbatsov/projectile/issues/1886): Fix `(wrong-type-argument stringp nil)` error when running project commands in a newly created project by using `projectile-acquire-root` instead of `projectile-project-root` in `projectile--run-project-cmd`.
+* [#1456](https://github.com/bbatsov/projectile/issues/1456): Fix `projectile-replace-regexp` stopping when encountering a missing file by filtering nonexistent files from the replacement file list.
+* [#1687](https://github.com/bbatsov/projectile/issues/1687): Fix `projectile-grep-finished-hook` not running on subsequent grep calls due to buffer rename collision.
+* [#1939](https://github.com/bbatsov/projectile/issues/1939): Handle corrupted `projectile-known-projects-file` gracefully instead of crashing with `(wrong-type-argument listp ...)`.
 * [#1748](https://github.com/bbatsov/projectile/issues/1748): Fix `projectile-replace` falling back to the legacy Emacs 25/26 code path on Emacs 27+ because `fileloop` was not loaded.
 * [#1741](https://github.com/bbatsov/projectile/issues/1741): Fix `projectile-replace` treating the search string as a regexp instead of a literal string on Emacs 27+.
 * [#1729](https://github.com/bbatsov/projectile/issues/1729): Fix `projectile-root-top-down` to actually return the topmost matching project root instead of the bottommost.

projectile.el

@@ -4513,7 +4513,7 @@ With REGEXP given, don't query the user for a regexp."
               ;; scoped to the current root to allow multiple concurrent grep
               ;; operations, one per root
               (with-current-buffer "*grep*"
-                (rename-buffer (concat "*grep <" root-dir ">*"))))))))
+                (rename-buffer (concat "*grep <" root-dir ">*") t)))))))
     (run-hooks 'projectile-grep-finished-hook)))
 
 ;;;###autoload
@@ -5036,12 +5036,13 @@ to run the replacement."
                      (format "Replace regexp %s with: " old-text))))
          (files
           ;; We have to reject directories as a workaround to work with git submodules.
+          ;; We also reject nonexistent files to avoid errors during replacement.
           ;;
           ;; We can't narrow the list of files with
           ;; `projectile-files-with-string' because those regexp tools
           ;; don't support Emacs regular expressions.
           (cl-remove-if
-           #'file-directory-p
+           (lambda (f) (or (file-directory-p f) (not (file-exists-p f))))
            (mapcar #'(lambda (file) (expand-file-name file directory))
                    (projectile-dir-files directory)))))
     ;; FIXME: Probably would fail on Emacs 27+, fourth argument is gone.
@@ -5930,11 +5931,14 @@ Return a list of projects removed."
 (defun projectile-load-known-projects ()
   "Load saved projects from `projectile-known-projects-file'.
 Also set `projectile-known-projects'."
-  (setq projectile-known-projects
-        (projectile-unserialize projectile-known-projects-file))
-  (setq projectile-known-projects-on-file
-        (and (sequencep projectile-known-projects)
-             (copy-sequence projectile-known-projects))))
+  (let ((data (projectile-unserialize projectile-known-projects-file)))
+    (setq projectile-known-projects
+          (if (and (listp data) (null (cdr (last data)))) data nil))
+    (unless (equal data projectile-known-projects)
+      (message "Warning: Projectile known projects file was corrupted, ignoring saved data"))
+    (setq projectile-known-projects-on-file
+          (and (sequencep projectile-known-projects)
+               (copy-sequence projectile-known-projects)))))
 
 (defun projectile-save-known-projects ()
   "Save PROJECTILE-KNOWN-PROJECTS to PROJECTILE-KNOWN-PROJECTS-FILE."
@@ -5952,7 +5956,8 @@ overwriting each other's changes."
   (let* ((known-now projectile-known-projects)
          (known-on-last-sync projectile-known-projects-on-file)
          (known-on-file
-          (projectile-unserialize projectile-known-projects-file))
+          (let ((data (projectile-unserialize projectile-known-projects-file)))
+            (if (and (listp data) (null (cdr (last data)))) data nil)))
          (removed-after-sync (projectile-difference known-on-last-sync known-now))
          (removed-in-other-process
           (projectile-difference known-on-last-sync known-on-file))