feat: add current-location detection to the weather picker

Geolocation used to live in a separate command, so getting weather for where you are meant knowing a second command existed. I added a "Current location (detect)" entry pinned to the top of the M-x wttrin picker. Selecting it detects your location and shows its weather. If the guess is wrong (VPN, hotspot) the detected city is visible in the header, so you reopen the picker and type one. Press d to keep the detected city as the default.

The entry is pinned first through a completion table whose display-sort-function holds against completion frameworks that re-sort, and it never enters location history or the cache as a place.

A new wttrin-geolocation-enabled (default t) turns every geolocation surface off for users who want that: the picker entry, the auto-detect favorite, and the command. It stays on by default.

The older wttrin-set-location-from-geolocation command is now obsolete in favor of the picker. Its customize-save-variable persistence advice is replaced by savehist, which already carries the favorite across sessions.

5 files changed, 267 insertions, 12 deletions

diff --git a/tests/test-wttrin-geolocation-sentinel.el b/tests/test-wttrin-geolocation-sentinel.el
new file mode 100644
index 0000000..0536173
--- /dev/null
+++ b/tests/test-wttrin-geolocation-sentinel.el
@@ -0,0 +1,212 @@
+;;; test-wttrin-geolocation-sentinel.el --- Tests for the picker geolocation sentinel -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2024-2026 Craig Jennings
+
+;;; Commentary:
+;; Unit tests for the "Current location (detect)" picker sentinel: its presence
+;; and position in `wttrin--completion-candidates', the selection routing in
+;; `wttrin--query-selection' (literal vs detect-then-query), and the guard that
+;; keeps the sentinel out of location history.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+(require 'wttrin)
+(require 'wttrin-geolocation)
+(require 'testutil-wttrin)
+
+;;; wttrin--completion-candidates — sentinel presence and position
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-first-candidate ()
+  "Normal: the sentinel is the first completion candidate."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((wttrin-favorite-location nil)
+            (wttrin-default-locations '("Honolulu, HI"))
+            (wttrin--location-history '("Tokyo")))
+        (should (equal wttrin--geolocation-sentinel
+                       (car (wttrin--completion-candidates)))))
+    (testutil-wttrin-teardown)))
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-first-even-with-favorite ()
+  "Normal: the sentinel precedes a string favorite in the candidate list."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((wttrin-favorite-location "New Orleans, LA")
+            (wttrin-default-locations '("Honolulu, HI"))
+            (wttrin--location-history nil))
+        (should (equal (list wttrin--geolocation-sentinel
+                             "New Orleans, LA" "Honolulu, HI")
+                       (wttrin--completion-candidates))))
+    (testutil-wttrin-teardown)))
+
+;;; wttrin--sort-completions — pin the sentinel first
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-sort-pins-first ()
+  "Normal: the sentinel is moved to the front, the rest keep their order.
+Sorting completion UIs (vertico, icomplete) call the metadata
+display-sort-function, so this is what keeps the sentinel pinned."
+  (should (equal (list wttrin--geolocation-sentinel "Honolulu, HI" "Tokyo")
+                 (wttrin--sort-completions
+                  (list "Honolulu, HI" wttrin--geolocation-sentinel "Tokyo")))))
+
+(ert-deftest test-wttrin-geolocation-sentinel-boundary-sort-no-sentinel-unchanged ()
+  "Boundary: a list without the sentinel is returned in its original order."
+  (should (equal '("Honolulu, HI" "Tokyo")
+                 (wttrin--sort-completions '("Honolulu, HI" "Tokyo")))))
+
+(ert-deftest test-wttrin-geolocation-sentinel-boundary-sort-empty ()
+  "Boundary: an empty candidate list sorts to empty."
+  (should (null (wttrin--sort-completions nil))))
+
+;;; wttrin--completion-table — metadata + completion
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-table-metadata-sort-fn ()
+  "Normal: the table advertises the pin-first display-sort-function."
+  (let* ((table (wttrin--completion-table
+                 (list wttrin--geolocation-sentinel "Tokyo")))
+         (meta (funcall table "" nil 'metadata)))
+    (should (eq #'wttrin--sort-completions
+                (cdr (assq 'display-sort-function (cdr meta)))))))
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-table-completes-candidates ()
+  "Normal: the table completes over the candidates it was given."
+  (let ((table (wttrin--completion-table
+                (list wttrin--geolocation-sentinel "Tokyo" "Paris"))))
+    (should (equal (sort (list wttrin--geolocation-sentinel "Tokyo" "Paris")
+                         #'string-lessp)
+                   (sort (all-completions "" table) #'string-lessp)))))
+
+;;; wttrin interactive entry — delegates to routing
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-entry-delegates-to-query-selection ()
+  "Normal: the interactive `wttrin' command routes its picker selection
+through `wttrin--query-selection' (smoke test of the entry wrapper)."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((routed nil))
+        (cl-letf (((symbol-function 'completing-read)
+                   (lambda (&rest _) "London, GB"))
+                  ((symbol-function 'wttrin--query-selection)
+                   (lambda (loc) (setq routed loc))))
+          (call-interactively 'wttrin))
+        (should (equal "London, GB" routed)))
+    (testutil-wttrin-teardown)))
+
+;;; wttrin--query-selection — routing
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-typed-location-queries-literally ()
+  "Normal: a typed location is passed straight to `wttrin-query'."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((captured nil))
+        (cl-letf (((symbol-function 'wttrin-query)
+                   (lambda (loc) (setq captured loc))))
+          (wttrin--query-selection "Paris"))
+        (should (equal "Paris" captured)))
+    (testutil-wttrin-teardown)))
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-routes-to-detect-then-query ()
+  "Normal: selecting the sentinel detects, then queries the resolved city."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((captured nil))
+        (cl-letf (((symbol-function 'wttrin-geolocation-detect)
+                   (lambda (callback) (funcall callback "Austin, TX")))
+                  ((symbol-function 'wttrin-query)
+                   (lambda (loc) (setq captured loc)))
+                  ((symbol-function 'message) (lambda (&rest _) nil)))
+          (wttrin--query-selection wttrin--geolocation-sentinel))
+        (should (equal "Austin, TX" captured)))
+    (testutil-wttrin-teardown)))
+
+(ert-deftest test-wttrin-geolocation-sentinel-error-detect-failure-no-query ()
+  "Error: a failed detection does not query and does not mutate the favorite."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((queried nil)
+            (wttrin-favorite-location "New Orleans, LA"))
+        (cl-letf (((symbol-function 'wttrin-geolocation-detect)
+                   (lambda (callback) (funcall callback nil)))
+                  ((symbol-function 'wttrin-query)
+                   (lambda (_loc) (setq queried t)))
+                  ((symbol-function 'message) (lambda (&rest _) nil)))
+          (wttrin--query-selection wttrin--geolocation-sentinel))
+        (should-not queried)
+        (should (equal "New Orleans, LA" wttrin-favorite-location)))
+    (testutil-wttrin-teardown)))
+
+;;; sentinel never enters history
+
+(ert-deftest test-wttrin-geolocation-sentinel-boundary-never-added-to-history ()
+  "Boundary: the sentinel string is never recorded in location history."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((wttrin-default-locations '())
+            (wttrin--location-history nil))
+        (wttrin--add-to-location-history wttrin--geolocation-sentinel)
+        (should (null wttrin--location-history)))
+    (testutil-wttrin-teardown)))
+
+;;; wttrin-geolocation-enabled — opt-out switch
+
+(ert-deftest test-wttrin-geolocation-sentinel-normal-disabled-hides-sentinel ()
+  "Normal: with geolocation disabled, the sentinel is not offered."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((wttrin-geolocation-enabled nil)
+            (wttrin-favorite-location nil)
+            (wttrin-default-locations '("Honolulu, HI"))
+            (wttrin--location-history '("Tokyo")))
+        (should-not (member wttrin--geolocation-sentinel
+                            (wttrin--completion-candidates)))
+        (should (equal '("Honolulu, HI" "Tokyo")
+                       (wttrin--completion-candidates))))
+    (testutil-wttrin-teardown)))
+
+(ert-deftest test-wttrin-geolocation-sentinel-boundary-enabled-shows-sentinel ()
+  "Boundary: with geolocation enabled (default), the sentinel is offered first."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((wttrin-geolocation-enabled t)
+            (wttrin-favorite-location nil)
+            (wttrin-default-locations '("Honolulu, HI"))
+            (wttrin--location-history nil))
+        (should (equal wttrin--geolocation-sentinel
+                       (car (wttrin--completion-candidates)))))
+    (testutil-wttrin-teardown)))
+
+(ert-deftest test-wttrin-geolocation-sentinel-error-disabled-detect-then-query-no-detect ()
+  "Error: with geolocation disabled, detect-then-query does not detect or query."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((detected nil)
+            (queried nil)
+            (wttrin-geolocation-enabled nil))
+        (cl-letf (((symbol-function 'wttrin-geolocation-detect)
+                   (lambda (_cb) (setq detected t)))
+                  ((symbol-function 'wttrin-query)
+                   (lambda (_loc) (setq queried t)))
+                  ((symbol-function 'message) (lambda (&rest _) nil)))
+          (wttrin--detect-then-query))
+        (should-not detected)
+        (should-not queried))
+    (testutil-wttrin-teardown)))
+
+(ert-deftest test-wttrin-geolocation-sentinel-boundary-disabled-favorite-no-autodetect ()
+  "Boundary: with geolocation disabled, the t-favorite auto-detect does not fire."
+  (testutil-wttrin-setup)
+  (unwind-protect
+      (let ((detected nil)
+            (wttrin-geolocation-enabled nil)
+            (wttrin--favorite-location-pending nil))
+        (cl-letf (((symbol-function 'wttrin-geolocation-detect)
+                   (lambda (_cb) (setq detected t))))
+          (wttrin--start-favorite-location-detect))
+        (should-not detected)
+        (should-not wttrin--favorite-location-pending))
+    (testutil-wttrin-teardown)))
+
+(provide 'test-wttrin-geolocation-sentinel)
+;;; test-wttrin-geolocation-sentinel.el ends here
diff --git a/tests/test-wttrin-location-history.el b/tests/test-wttrin-location-history.el
index 61b495c..4af8235 100644
--- a/tests/test-wttrin-location-history.el
+++ b/tests/test-wttrin-location-history.el
@@ -113,31 +113,37 @@
 ;;; wttrin--completion-candidates
 
 (ert-deftest test-wttrin-location-history-normal-candidates-defaults-then-history ()
-  "Candidates list defaults first, then history."
+  "Candidates list the sentinel, then defaults, then history."
   (test-wttrin-location-history-setup)
   (unwind-protect
-      (let ((wttrin-default-locations '("Honolulu, HI" "Berkeley, CA"))
+      (let ((wttrin-favorite-location nil)
+            (wttrin-default-locations '("Honolulu, HI" "Berkeley, CA"))
             (wttrin--location-history '("Tokyo" "Paris")))
-        (should (equal '("Honolulu, HI" "Berkeley, CA" "Tokyo" "Paris")
+        (should (equal (list wttrin--geolocation-sentinel
+                             "Honolulu, HI" "Berkeley, CA" "Tokyo" "Paris")
                        (wttrin--completion-candidates))))
     (test-wttrin-location-history-teardown)))
 
 (ert-deftest test-wttrin-location-history-normal-candidates-only-defaults ()
-  "With empty history, candidates are just the defaults."
+  "With empty history, candidates are the sentinel then the defaults."
   (test-wttrin-location-history-setup)
   (unwind-protect
-      (let ((wttrin-default-locations '("Honolulu, HI"))
+      (let ((wttrin-favorite-location nil)
+            (wttrin-default-locations '("Honolulu, HI"))
             (wttrin--location-history nil))
-        (should (equal '("Honolulu, HI") (wttrin--completion-candidates))))
+        (should (equal (list wttrin--geolocation-sentinel "Honolulu, HI")
+                       (wttrin--completion-candidates))))
     (test-wttrin-location-history-teardown)))
 
 (ert-deftest test-wttrin-location-history-normal-candidates-only-history ()
-  "With empty defaults, candidates are just the history."
+  "With empty defaults, candidates are the sentinel then the history."
   (test-wttrin-location-history-setup)
   (unwind-protect
-      (let ((wttrin-default-locations '())
+      (let ((wttrin-favorite-location nil)
+            (wttrin-default-locations '())
             (wttrin--location-history '("Tokyo")))
-        (should (equal '("Tokyo") (wttrin--completion-candidates))))
+        (should (equal (list wttrin--geolocation-sentinel "Tokyo")
+                       (wttrin--completion-candidates))))
     (test-wttrin-location-history-teardown)))
 
 ;;; wttrin-remove-location-history
diff --git a/tests/test-wttrin-make-default.el b/tests/test-wttrin-make-default.el
index 623200c..e715e12 100644
--- a/tests/test-wttrin-make-default.el
+++ b/tests/test-wttrin-make-default.el
@@ -143,7 +143,8 @@ stale cache and fetches fresh weather for the new location immediately."
         (wttrin--location-history nil)
         (wttrin-favorite-location "Reykjavik"))
     (should (equal (wttrin--completion-candidates)
-                   '("Reykjavik" "Honolulu, HI" "Berkeley, CA")))))
+                   (list wttrin--geolocation-sentinel
+                         "Reykjavik" "Honolulu, HI" "Berkeley, CA")))))
 
 ;;; Boundary Cases
 
@@ -161,7 +162,7 @@ stale cache and fetches fresh weather for the new location immediately."
         (wttrin--location-history '("Oslo, NO"))
         (wttrin-favorite-location nil))
     (should (equal (wttrin--completion-candidates)
-                   '("Honolulu, HI" "Oslo, NO")))))
+                   (list wttrin--geolocation-sentinel "Honolulu, HI" "Oslo, NO")))))
 
 ;;; --------------------------------------------------------------------------
 ;;; keymap binding
diff --git a/tests/test-wttrin-requery.el b/tests/test-wttrin-requery.el
index d6a8beb..5d52b36 100644
--- a/tests/test-wttrin-requery.el
+++ b/tests/test-wttrin-requery.el
@@ -105,6 +105,8 @@ to the core requery function."
   (test-wttrin-requery-setup)
   (unwind-protect
       (let ((offered-collection nil)
+            (wttrin-favorite-location nil)
+            (wttrin--location-history nil)
             (wttrin-default-locations '("Paris" "London" "Tokyo")))
         (cl-letf (((symbol-function 'completing-read)
                    (lambda (_prompt collection &rest _args)
@@ -113,7 +115,12 @@ to the core requery function."
                   ((symbol-function 'wttrin--requery-location)
                    (lambda (_loc) nil)))
           (wttrin-requery)
-          (should (equal offered-collection '("Paris" "London" "Tokyo")))))
+          ;; The collection is now a completion table (a function) that pins
+          ;; the sentinel first; check the candidates it completes over.
+          (should (equal (list wttrin--geolocation-sentinel
+                               "Paris" "London" "Tokyo")
+                         (wttrin--sort-completions
+                          (all-completions "" offered-collection))))))
     (test-wttrin-requery-teardown)))
 
 (ert-deftest test-wttrin-requery-boundary-single-default-prefills ()
diff --git a/tests/test-wttrin-set-location-from-geolocation.el b/tests/test-wttrin-set-location-from-geolocation.el
index 170d0fb..e7c3a97 100644
--- a/tests/test-wttrin-set-location-from-geolocation.el
+++ b/tests/test-wttrin-set-location-from-geolocation.el
@@ -118,5 +118,34 @@
                          messages)))
     (test-wttrin-set-location-from-geolocation-teardown)))
 
+;;; Opt-out
+
+(ert-deftest test-wttrin-set-location-from-geolocation-boundary-disabled-no-detect ()
+  "Boundary: with geolocation disabled, the command neither detects nor sets."
+  (test-wttrin-set-location-from-geolocation-setup)
+  (setq wttrin-favorite-location "Pre-existing, Place")
+  (unwind-protect
+      (let ((detected nil)
+            (wttrin-geolocation-enabled nil))
+        (cl-letf (((symbol-function 'wttrin-geolocation-detect)
+                   (lambda (_cb) (setq detected t)))
+                  ((symbol-function 'message) (lambda (&rest _) nil)))
+          (wttrin-set-location-from-geolocation))
+        (should-not detected)
+        (should (string= "Pre-existing, Place" wttrin-favorite-location)))
+    (test-wttrin-set-location-from-geolocation-teardown)))
+
+;;; Deprecation
+
+(ert-deftest test-wttrin-set-location-from-geolocation-normal-marked-obsolete ()
+  "Normal: the command is marked obsolete with a steering message.
+The favorite-setting behavior is preserved (see the Normal cases above);
+this only asserts the obsolescence marker so callers get a deprecation
+notice steering them to the picker."
+  (let ((info (get 'wttrin-set-location-from-geolocation 'byte-obsolete-info)))
+    (should info)
+    ;; Option 1: a steering string, not an alias to another function.
+    (should (stringp (nth 0 info)))))
+
 (provide 'test-wttrin-set-location-from-geolocation)
 ;;; test-wttrin-set-location-from-geolocation.el ends here