fix: debug-wttrin-show-raw broken by async API change

debug-wttrin-show-raw called wttrin--get-cached-or-fetch with 1 arg,
but the function now requires 2 (location + callback) since the async
refactor. Rewrote to use the callback pattern. Also handles nil
response gracefully.

2 files changed, 120 insertions, 13 deletions

diff --git a/tests/test-debug-wttrin-show-raw.el b/tests/test-debug-wttrin-show-raw.el
new file mode 100644
index 0000000..ae2f750
--- /dev/null
+++ b/tests/test-debug-wttrin-show-raw.el
@@ -0,0 +1,104 @@
+;;; test-debug-wttrin-show-raw.el --- Tests for debug-wttrin-show-raw -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2025 Craig Jennings
+
+;;; Commentary:
+
+;; Unit tests for debug-wttrin-show-raw function.
+;; Tests that the debug display shows raw weather data with line numbers.
+
+;;; Code:
+
+(require 'ert)
+(require 'wttrin)
+(require 'testutil-wttrin)
+
+;; Load wttrin-debug for the function under test
+(require 'wttrin-debug
+         (expand-file-name "wttrin-debug.el"
+                           (file-name-directory (locate-library "wttrin"))))
+
+;;; Setup and Teardown
+
+(defun test-debug-wttrin-show-raw-setup ()
+  "Setup for debug-wttrin-show-raw tests."
+  (testutil-wttrin-setup)
+  (when (get-buffer "*wttrin-debug*")
+    (kill-buffer "*wttrin-debug*")))
+
+(defun test-debug-wttrin-show-raw-teardown ()
+  "Teardown for debug-wttrin-show-raw tests."
+  (testutil-wttrin-teardown)
+  (when (get-buffer "*wttrin-debug*")
+    (kill-buffer "*wttrin-debug*")))
+
+;;; Normal Cases
+
+(ert-deftest test-debug-wttrin-show-raw-normal-creates-debug-buffer ()
+  "Calling show-raw should create the *wttrin-debug* buffer."
+  (test-debug-wttrin-show-raw-setup)
+  (unwind-protect
+      (progn
+        (testutil-wttrin-mock-http-response "Line one\nLine two\nLine three"
+          (debug-wttrin-show-raw "Paris"))
+        (should (get-buffer "*wttrin-debug*")))
+    (test-debug-wttrin-show-raw-teardown)))
+
+(ert-deftest test-debug-wttrin-show-raw-normal-adds-line-numbers ()
+  "Each line of raw data should be prefixed with its line number."
+  (test-debug-wttrin-show-raw-setup)
+  (unwind-protect
+      (progn
+        (testutil-wttrin-mock-http-response "Alpha\nBravo\nCharlie"
+          (debug-wttrin-show-raw "Paris"))
+        (with-current-buffer "*wttrin-debug*"
+          (let ((contents (buffer-string)))
+            (should (string-match-p "^ *1: Alpha" contents))
+            (should (string-match-p "^ *2: Bravo" contents))
+            (should (string-match-p "^ *3: Charlie" contents)))))
+    (test-debug-wttrin-show-raw-teardown)))
+
+(ert-deftest test-debug-wttrin-show-raw-normal-fetches-correct-location ()
+  "The function should fetch weather for the specified location."
+  (test-debug-wttrin-show-raw-setup)
+  (unwind-protect
+      (let ((fetched-location nil))
+        (cl-letf (((symbol-function 'wttrin--get-cached-or-fetch)
+                   (lambda (location callback)
+                     (setq fetched-location location)
+                     (funcall callback "data"))))
+          (debug-wttrin-show-raw "Berlin, DE")
+          (should (equal fetched-location "Berlin, DE"))))
+    (test-debug-wttrin-show-raw-teardown)))
+
+;;; Boundary Cases
+
+(ert-deftest test-debug-wttrin-show-raw-boundary-single-line ()
+  "Single-line response should get line number 1."
+  (test-debug-wttrin-show-raw-setup)
+  (unwind-protect
+      (progn
+        (testutil-wttrin-mock-http-response "Just one line"
+          (debug-wttrin-show-raw "Paris"))
+        (with-current-buffer "*wttrin-debug*"
+          (let ((contents (buffer-string)))
+            (should (string-match-p "^ *1: Just one line" contents)))))
+    (test-debug-wttrin-show-raw-teardown)))
+
+;;; Error Cases
+
+(ert-deftest test-debug-wttrin-show-raw-error-nil-response-should-not-crash ()
+  "When the fetch returns nil, the function should handle it gracefully."
+  (test-debug-wttrin-show-raw-setup)
+  (unwind-protect
+      (cl-letf (((symbol-function 'wttrin--get-cached-or-fetch)
+                 (lambda (_location callback)
+                   (funcall callback nil))))
+        ;; Should not crash
+        (debug-wttrin-show-raw "BadLocation")
+        ;; Buffer should exist even on error
+        (should (get-buffer "*wttrin-debug*")))
+    (test-debug-wttrin-show-raw-teardown)))
+
+(provide 'test-debug-wttrin-show-raw)
+;;; test-debug-wttrin-show-raw.el ends here
diff --git a/wttrin-debug.el b/wttrin-debug.el
index a0576a4..e1d4697 100644
--- a/wttrin-debug.el
+++ b/wttrin-debug.el
@@ -41,19 +41,22 @@
   "Fetch and display raw wttr.in data for LOCATION with line numbers.
 This is useful for debugging header parsing issues."
   (interactive "sLocation: ")
-  (let ((raw-string (wttrin--get-cached-or-fetch location)))
-    (with-current-buffer (get-buffer-create "*wttrin-debug*")
-      (erase-buffer)
-      (insert raw-string)
-      (goto-char (point-min))
-      (let ((line-num 1))
-        (while (not (eobp))
-          (beginning-of-line)
-          (insert (format "%2d: " line-num))
-          (setq line-num (1+ line-num))
-          (forward-line 1)))
-      (goto-char (point-min))
-      (switch-to-buffer (current-buffer)))))
+  (wttrin--get-cached-or-fetch
+   location
+   (lambda (raw-string)
+     (with-current-buffer (get-buffer-create "*wttrin-debug*")
+       (erase-buffer)
+       (when raw-string
+         (insert raw-string))
+       (goto-char (point-min))
+       (let ((line-num 1))
+         (while (not (eobp))
+           (beginning-of-line)
+           (insert (format "%2d: " line-num))
+           (setq line-num (1+ line-num))
+           (forward-line 1)))
+       (goto-char (point-min))
+       (switch-to-buffer (current-buffer))))))
 
 ;;;###autoload
 (defun debug-wttrin-enable ()