Improve collecting of citation keys

* lisp/textmodes/reftex-cite.el (reftex-all-used-citation-keys):
Improve regexp for matching various cite commands incl. optional
arguments.
Recognize comments more robustly and don't interpret the control
symbol \% as a comment starter.  (bug#56655)

* test/lisp/textmodes/reftex-tests.el
(reftex-all-used-citation-keys): New test.

2 files changed, 174 insertions, 13 deletions

diff --git a/lisp/textmodes/reftex-cite.el b/lisp/textmodes/reftex-cite.el
index 26b14ebc79e..f3f95627af1 100644
--- a/lisp/textmodes/reftex-cite.el
+++ b/lisp/textmodes/reftex-cite.el
@@ -1116,10 +1116,10 @@ recommended for follow mode.  It works OK for individual lookups."
         (setq bibtype (reftex-bib-or-thebib))
         (cond
          ((eq bibtype 'bib)
-;        ((assq 'bib (symbol-value reftex-docstruct-symbol))
+          ;; ((assq 'bib (symbol-value reftex-docstruct-symbol))
           (setq bibfile-list (reftex-get-bibfile-list)))
          ((eq bibtype 'thebib)
-;        ((assq 'thebib (symbol-value reftex-docstruct-symbol))
+          ;; ((assq 'thebib (symbol-value reftex-docstruct-symbol))
           (setq bibfile-list
                 (reftex-uniquify
                  (mapcar #'cdr
@@ -1142,8 +1142,35 @@ recommended for follow mode.  It works OK for individual lookups."
 
 ;;; Global BibTeX file
 (defun reftex-all-used-citation-keys ()
+  "Return a list of all citation keys used in document."
   (reftex-access-scan-info)
-  (let ((files (reftex-all-document-files)) file keys kk k)
+  ;; FIXME: multicites macros provided by biblatex
+  ;; are not covered in this function.
+  (let ((files (reftex-all-document-files))
+        (re (concat "\\\\"
+                    "\\(?:"
+                    ;; biblatex volcite macros take these args:
+                    ;; \volcite[prenote]{volume}[pages]{key}
+                    ;; so cater for the first 3 args:
+                    (regexp-opt '("volcite"  "Volcite"
+                                  "pvolcite" "Pvolcite"
+                                  "fvolcite" "ftvolcite"
+                                  "svolcite" "Svolcite"
+                                  "tvolcite" "Tvolcite"
+                                  "avolcite" "Avolcite"))
+                    "\\(?:\\[[^]]*\\]\\)?"
+                    "{[^}]*}"
+                    "\\(?:\\[[^]]*\\]\\)?"
+                    "\\|"
+                    ;; Other cite macros usually go like:
+                    ;; \cite[prenote][postnote]{key}
+                    ;; so cater for the optional args:
+                    "\\(?:bibentry\\|[a-zA-Z]*[Cc]ite[a-zA-Z*]*\\)"
+                    "\\(?:\\[[^]]*\\]\\)\\{0,2\\}"
+                    "\\)"
+                    ;; Now match the key:
+                    "{\\([^}]+\\)}"))
+        file keys kk k)
     (save-current-buffer
       (while (setq file (pop files))
         (set-buffer (reftex-get-file-buffer-force file 'mark))
@@ -1151,14 +1178,17 @@ recommended for follow mode.  It works OK for individual lookups."
           (save-restriction
             (widen)
             (goto-char (point-min))
-            (while (re-search-forward "\\(?:^\\|\\=\\)[^%\n\r]*?\\\\\\(bibentry\\|[a-zA-Z]*cite[a-zA-Z]*\\)\\(\\[[^]]*\\]\\)?{\\([^}]+\\)}" nil t)
-              (setq kk (match-string-no-properties 3))
-              (while (string-match "%.*\n?" kk)
-                (setq kk (replace-match "" t t kk)))
-              (setq kk (split-string kk "[, \t\r\n]+"))
-              (while (setq k (pop kk))
-                (or (member k keys)
-                    (setq keys (cons k keys)))))))))
+            (while (re-search-forward re nil t)
+              ;; Make sure we're not inside a comment:
+              (unless (save-match-data
+                        (nth 4 (syntax-ppss)))
+                (setq kk (match-string-no-properties 1))
+                (while (string-match "%.*\n?" kk)
+                  (setq kk (replace-match "" t t kk)))
+                (setq kk (split-string kk "[, \t\r\n]+"))
+                (while (setq k (pop kk))
+                  (or (member k keys)
+                      (setq keys (cons k keys))))))))))
     (reftex-kill-temporary-buffers)
     keys))
 
diff --git a/test/lisp/textmodes/reftex-tests.el b/test/lisp/textmodes/reftex-tests.el
index 9ef41088d1e..97ff3908177 100644
--- a/test/lisp/textmodes/reftex-tests.el
+++ b/test/lisp/textmodes/reftex-tests.el
@@ -190,8 +190,8 @@
 
 (ert-deftest reftex-format-citation-test ()
   "Test `reftex-format-citation'."
-  (let ((entry (reftex-parse-bibtex-entry
-"@article{Foo13,
+  (let ((entry (reftex-parse-bibtex-entry "\
+@article{Foo13,
   author =    {Jane Roe and John Doe and Jane Q. Taxpayer},
   title =        {Some Article},
   journal =    {Some Journal},
@@ -202,6 +202,137 @@
     (should (string= (reftex-format-citation entry "%l:%A:%y:%t %j %P %a")
                      "Foo13:Jane Roe:2013:Some Article Some Journal 1 Jane Roe, John Doe \\& Jane Taxpayer"))))
 
+(ert-deftest reftex-all-used-citation-keys ()
+  "Test `reftex-all-used-citation-keys'.
+Take the cite macros provided by biblatex package as reference."
+  (ert-with-temp-directory temp-dir
+    (let ((tex-file (expand-file-name "keys.tex" temp-dir))
+          keys)
+      (with-temp-buffer
+        (insert "\
+\\documentclass{article}
+\\usepackage{biblatex}
+\\begin{document}
+
+Standard commands:
+\\cite[pre][pos]{cite:2022}
+\\Cite[pos]{Cite:2022}
+\\parencite{parencite:2022}
+\\Parencite[pre][]{Parencite:2022}
+\\footcite[][]{footcite:2022}
+\\footcitetext[pre][pos]{footcitetext:2022}
+
+Style specific commands:
+\\textcite{textcite:2022}
+\\Textcite[pos]{Textcite:2022}
+\\smartcite[pre][pos]{smartcite:2022}
+\\Smartcite[pre][]{Smartcite:2022}
+\\cite*[pre][pos]{cite*:2022}
+\\parencite*[][]{parencite*:2022}
+
+Style independent commands:
+\\autocite[pre][pos]{autocite:2022}
+\\autocite*[pos]{autocite*:2022}
+\\Autocite[pre][]{Autocite:2022}
+\\Autocite*{Autocite*:2022}
+
+Text commands:
+\\citeauthor[pre][pos]{citeauthor:2022}
+\\citeauthor*[pre][]{citeauthor*:2022}
+\\Citeauthor[pos]{Citeauthor:2022}
+\\Citeauthor*{Citeauthor*:2022}
+\\citetitle[][]{citetitle:2022}
+\\citetitle*[pre][pos]{citetitle*:2022}
+\\citeyear[pre][pos]{citeyear:2022}
+\\citeyear*[pre][pos]{citeyear*:2022}
+\\citedate[pre][pos]{citedate:2022}
+\\citedate*[pre][pos]{citedate*:2022}
+\\citeurl[pre][pos]{citeurl:2022}
+
+Special commands:
+\\nocite{nocite:2022}
+\\fullcite[pos]{fullcite:2022}
+\\footfullcite[][]{fullfootcite:2022}
+``volcite'' macros have different number of args.
+\\volcite{2}{volcite:2022}
+\\Volcite[pre]{1}{Volcite:2022}
+\\pvolcite{1}[pg]{pvolcite:2022}
+\\Pvolcite[pre]{2}[pg]{Pvolcite:2022}
+\\fvolcite[pre]{3}[pg]{fvolcite:2022}
+\\ftvolcite[pre]{3}[pg]{ftvolcite:2022}
+\\svolcite[pre]{2}[pg]{svolcite:2022}
+\\Svolcite[pre]{4}[pg]{Svolcite:2022}
+\\tvolcite[pre]{5}[pg]{tvolcite:2022}
+\\Tvolcite[pre]{2}[pg]{Tvolcite:2022}
+\\avolcite[pre]{3}[pg]{avolcite:2022}
+\\Avolcite[pre]{1}[pg]{Avolcite:2022}
+\\Notecite[pre]{Notecite:2022}
+\\pnotecite[pre]{pnotecite:2022}
+\\Pnotecite[pre]{Pnotecite:2022}
+\\fnotecite[pre]{fnotecite:2022}
+
+Natbib compatibility commands:
+\\citet{citet:2022}
+\\citet*[pre][pos]{citet*:2022}
+\\citep[pre][pos]{citep:2022}
+\\citep*[pos]{citep*:2022}
+\\citealt[pre][]{citealt:2022}
+\\citealt*[][]{citealt*:2022}
+\\citealp[pre][pos]{citealp:2022}
+\\citealp*{citealp*:2022}
+\\Citet[pre][pos]{Citet:2022}
+\\Citet*[pre][pos]{Citet*:2022}
+\\Citep[pre][pos]{Citep:2022}
+\\Citep*[pre][pos]{Citep*:2022}
+
+Test for bug#56655:
+There was a few \\% of increase in budget \\Citep*{bug:56655}.
+
+And this should be % \\cite{ignored}.
+\\end{document}")
+        (write-region (point-min) (point-max) tex-file))
+      (find-file tex-file)
+      (setq keys (reftex-all-used-citation-keys))
+      (should (equal (sort keys #'string<)
+                     (sort '(;; Standard commands:
+                             "cite:2022"      "Cite:2022"
+                             "parencite:2022" "Parencite:2022"
+                             "footcite:2022"  "footcitetext:2022"
+                             ;; Style specific commands:
+                             "textcite:2022"  "Textcite:2022"
+                             "smartcite:2022" "Smartcite:2022"
+                             "cite*:2022" "parencite*:2022"
+                             ;; Style independent commands:
+                             "autocite:2022"  "autocite*:2022"
+                             "Autocite:2022"  "Autocite*:2022"
+                             ;; Text commands
+                             "citeauthor:2022" "citeauthor*:2022"
+                             "Citeauthor:2022" "Citeauthor*:2022"
+                             "citetitle:2022"  "citetitle*:2022"
+                             "citeyear:2022"   "citeyear*:2022"
+                             "citedate:2022"   "citedate*:2022"
+                             "citeurl:2022"
+                             ;; Special commands:
+                             "nocite:2022"     "fullcite:2022"
+                             "fullfootcite:2022"
+                             "volcite:2022"   "Volcite:2022"
+                             "pvolcite:2022"  "Pvolcite:2022"
+                             "fvolcite:2022"  "ftvolcite:2022"
+                             "svolcite:2022"  "Svolcite:2022"
+                             "tvolcite:2022"  "Tvolcite:2022"
+                             "avolcite:2022"  "Avolcite:2022"
+                             "Notecite:2022"  "pnotecite:2022"
+                             "Pnotecite:2022" "fnotecite:2022"
+                             ;; Natbib compatibility commands:
+                             "citet:2022"   "citet*:2022"
+                             "citep:2022"   "citep*:2022"
+                             "citealt:2022" "citealt*:2022"
+                             "citealp:2022" "citealp*:2022"
+                             "Citet:2022"   "Citet*:2022"
+                             "Citep:2022"   "Citep*:2022"
+                             "bug:56655")
+                           #'string<)))
+      (kill-buffer (file-name-nondirectory tex-file)))))
 
 ;;; Autoload tests