Allow tempo-define-template to reassign tags to new templates

* lisp/tempo.el (tempo-define-template): Update documentation string
to mention that existing tags can be reassigned new templates.
(tempo-add-tag): Allow reassigning tags to new templates.
Additionally, invalidate tag collections in all buffers if the global
tags list is being modified.
(tempo-invalidate-collection): Allow invalidating tag collections in
all buffers at the same time.
* test/lisp/tempo-tests.el (tempo-define-tag-globally-test): Add a
test to check that new templates plus tags can be defined from any
buffer and then immediately used in other buffers.
(tempo-overwrite-tag-test): Add a test to check that tags can be
reassigned templates.
* etc/NEWS: Announce changes in tempo.el.

(Bug#39555)

1 files changed, 39 insertions, 0 deletions

diff --git a/test/lisp/tempo-tests.el b/test/lisp/tempo-tests.el
index 0dd310b8531..bfe475910da 100644
--- a/test/lisp/tempo-tests.el
+++ b/test/lisp/tempo-tests.el
@@ -216,6 +216,45 @@
     (tempo-complete-tag)
     (should (equal (buffer-string) "Hello, World!"))))
 
+(ert-deftest tempo-define-tag-globally-test ()
+  "Testing usage of a template tag defined from another buffer."
+  (tempo-define-template "test" '("Hello, World!") "hello")
+
+  (with-temp-buffer
+    ;; Use a tag in buffer 1
+    (insert "hello")
+    (tempo-complete-tag)
+    (should (equal (buffer-string) "Hello, World!"))
+    (erase-buffer)
+
+    ;; Collection should not be dirty
+    (should-not tempo-dirty-collection)
+
+    ;; Define a tag on buffer 2
+    (with-temp-buffer
+      (tempo-define-template "test2" '("Now expanded.") "mytag"))
+
+    ;; I should be able to use this template back in buffer 1
+    (insert "mytag")
+    (tempo-complete-tag)
+    (should (equal (buffer-string) "Now expanded."))))
+
+(ert-deftest tempo-overwrite-tag-test ()
+  "Testing ability to reassign templates to tags."
+  (with-temp-buffer
+    ;; Define a tag and use it
+    (tempo-define-template "test-tag-1" '("abc") "footag")
+    (insert "footag")
+    (tempo-complete-tag)
+    (should (equal (buffer-string) "abc"))
+    (erase-buffer)
+
+    ;; Define a new template with the same tag
+    (tempo-define-template "test-tag-2" '("xyz") "footag")
+    (insert "footag")
+    (tempo-complete-tag)
+    (should (equal (buffer-string) "xyz"))))
+
 (ert-deftest tempo-expand-partial-tag-test ()
   "Testing expansion of a template with a tag, with a partial match."
   (with-temp-buffer