Fix this-command for selectrum-repeat (#439)

Co-authored-by: Clemens Radermacher <clemera@posteo.net>

CHANGELOG.md

@@ -255,6 +255,8 @@ The format is based on [Keep a Changelog].
 * Annotations or usage or `selectrum-candidate-display-suffix`
   property in file completions were overwritten for directories and
   not displayed, which has been fixed ([#256], [#255]).
+* `selectrum-repeat` did not set `this-command` when calling the
+  last command, which has been fixed ([#438], [#439]).
 
 [#100]: https://github.com/raxod502/selectrum/issues/100
 [#194]: https://github.com/raxod502/selectrum/issues/194
@@ -370,6 +372,8 @@ The format is based on [Keep a Changelog].
 [#427]: https://github.com/raxod502/selectrum/issues/427
 [#430]: https://github.com/raxod502/selectrum/pull/430
 [#432]: https://github.com/raxod502/selectrum/pull/432
+[#438]: https://github.com/raxod502/selectrum/issues/438
+[#439]: https://github.com/raxod502/selectrum/pull/439
 
 ## 3.0 (released 2020-10-20)
 ### Breaking changes

selectrum.el

@@ -2713,7 +2713,8 @@ shadows correctly."
   (unless selectrum--last-command
     (user-error "No Selectrum command has been run yet"))
   (let ((selectrum--repeat t))
-    (setq current-prefix-arg selectrum--last-prefix-arg)
+    (setq current-prefix-arg selectrum--last-prefix-arg
+          this-command selectrum--last-command)
     (call-interactively selectrum--last-command)))
 
 ;;;###autoload