Correct tag generation behavior/max eval depth error

TODO.org

@@ -229,7 +229,7 @@ ppp.el doesn't align plist values along the same column. It's also GPL, and I'm
    2. [ ] =chronometrist-statistics-count-active-days=
 4. [ ] Write integration tests using ecukes.
    1. Some feature definitions already exist in features/, write step definitions for them.
-5. [ ] Remove duplication - the three =chronometrist-*-history-populate= functions seem to have a common pattern of iterating over each hash value (a list of plists) in =chronometrist-events=, and over each element of that list.
+5. [X] Remove duplication - the three =chronometrist-*-history-populate= functions
 6. [ ] Remove duplication - extracting user key-values from a plist seems to be a common operation.
 7. [X] Extensions - redesign =chronometrist= such that it does not need to check for the availability of extensions (such as =chronometrist-goal=)
    * Could make two "transformer lists" - =chronometrist-list-format-transformers= and =chronometrist-entry-transformers=.

elisp/chronometrist-key-values.el

@@ -118,7 +118,7 @@ reversed and will have duplicate elements removed."
 Return the new value inserted into HISTORY-TABLE.
 
 HISTORY-TABLE must be a hash table. (see `chronometrist-tags-history')"
-  (chronometrist-map-file file
+  (chronometrist-mapc-file file
     (lambda (plist)
       (let ((new-tag-list  (plist-get plist :tags))
             (old-tag-lists (gethash task history-table)))
@@ -126,7 +126,7 @@ HISTORY-TABLE must be a hash table. (see `chronometrist-tags-history')"
              new-tag-list
              (puthash task
                       (if old-tag-lists
-                          (cons old-tag-lists new-tag-list)
+                          (append old-tag-lists (list new-tag-list))
                         (list new-tag-list))
                       history-table)))))
   (chronometrist-history-prep task history-table))
@@ -136,7 +136,7 @@ HISTORY-TABLE must be a hash table. (see `chronometrist-tags-history')"
 Return the new value inserted into HISTORY-TABLE.
 
 HISTORY-TABLE must be a hash table (see `chronometrist-key-history')."
-  (chronometrist-map-file file
+  (chronometrist-mapc-file file
     (lambda (plist)
       (catch 'quit
         (let* ((name  (plist-get plist :name))
@@ -157,7 +157,7 @@ HISTORY-TABLE must be a hash table (see `chronometrist-key-history')."
 HISTORY-TABLE must be a hash table. (see `chronometrist-value-history')"
   ;; Note - while keys are Lisp keywords, values may be any Lisp
   ;; object, including lists
-  (chronometrist-map-file file
+  (chronometrist-mapc-file file
     (lambda (plist)
       ;; We call them user-key-values because we filter out Chronometrist's
       ;; reserved key-values

elisp/chronometrist-sexp.el

@@ -20,8 +20,9 @@ STREAM (which is the value of `current-buffer')."
   `(with-current-buffer (find-file-noselect ,file)
      (save-excursion ,@body)))
 
-(defun chronometrist-map-file (file fn)
+(defun chronometrist-mapcar-file (file fn)
   "Run FN for each s-expression in FILE, from last to first.
+Return the values of FN as a list.
 FN must be a function accepting one argument."
   (declare (indent defun))
   (chronometrist-sexp-in-file file
@@ -29,13 +30,24 @@ FN must be a function accepting one argument."
     (cl-loop with var
       while (and (not (bobp))
                  (backward-list)
-                 (->> (current-buffer)
-                      (read )
-                      (ignore-errors )
-                      (setq var ))
+                 (setq var (ignore-errors (read (current-buffer))))
                  (backward-list))
       collect (funcall fn var))))
 
+(defun chronometrist-mapc-file (file fn)
+  "Run FN for each s-expression in FILE, from last to first.
+Return nil.
+FN must be a function accepting one argument."
+  (declare (indent defun))
+  (chronometrist-sexp-in-file file
+    (goto-char (point-max))
+    (cl-loop with var
+      while (and (not (bobp))
+                 (backward-list)
+                 (setq var (ignore-errors (read (current-buffer))))
+                 (backward-list))
+      do (funcall fn var))))
+
 ;;;; Queries
 (defun chronometrist-sexp-open-log ()
   "Open `chronometrist-file' in another window."

elisp/chronometrist.el

@@ -352,7 +352,7 @@ Argument _FS-EVENT is ignored."
               ((null file-change-type) nil)
               (t (chronometrist-events-populate))))
     (chronometrist-events-populate)
-    (--> (chronometrist-map-file chronometrist-file
+    (--> (chronometrist-mapcar-file chronometrist-file
            (lambda (plist)
              (plist-get plist :name)))
          (cl-remove-duplicates it :test #'equal)