feat(sources): single-issue source (favorites + open-issue-by-id)

I wired the issue kind into the same pipeline every other source uses, so a favorited issue renders in the buffer as its own subtree instead of the v1 browser punt. The new pearl-open-issue-by-id command does the same for an issue you type by identifier or id. It's handy when someone hands you ENG-123 and you'd rather read it in Pearl than a browser.

Linear's issue(id:) accepts both the UUID and the human identifier, so there's no resolution step. I fetch by whatever was given and build the :type issue source from the returned node, so the stored id and identifier stay authoritative. Refresh re-fetches the one issue and merges by LINEAR-ID like the filter and view sources.

Tests cover the source constructor, the header round-trip, and the fetch/render and command paths across Normal, Boundary, and Error.

1 files changed, 117 insertions, 0 deletions

diff --git a/tests/test-pearl-single-issue.el b/tests/test-pearl-single-issue.el
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+++ b/tests/test-pearl-single-issue.el
@@ -0,0 +1,117 @@
+;;; test-pearl-single-issue.el --- Tests for the single-issue source  -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2026 Craig Jennings
+
+;; Author: Craig Jennings <c@cjennings.net>
+
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Tests for the single-issue source: `pearl--issue-source' (id/identifier ->
+;; source plist), the `#+LINEAR-SOURCE' round-trip for that plist,
+;; `pearl--fetch-and-render-issue' (fetch one issue and render it like every
+;; other source), and `pearl-open-issue-by-id' (the jump-by-identifier command).
+;; The async fetch and the render boundary are stubbed at their seams.
+
+;;; Code:
+
+(require 'test-bootstrap (expand-file-name "test-bootstrap.el"))
+
+;;; pearl--issue-source
+
+(ert-deftest test-pearl-issue-source-builds-plist ()
+  "An id + identifier builds a `:type issue' source named by the identifier."
+  (let ((s (pearl--issue-source "u1" "ENG-7")))
+    (should (eq 'issue (plist-get s :type)))
+    (should (string= "u1" (plist-get s :id)))
+    (should (string= "ENG-7" (plist-get s :identifier)))
+    (should (string= "ENG-7" (plist-get s :name)))))
+
+(ert-deftest test-pearl-issue-source-name-falls-back-to-id ()
+  "With no identifier the source name falls back to the id, never nil."
+  (let ((s (pearl--issue-source "u1" nil)))
+    (should (string= "u1" (plist-get s :name)))))
+
+(ert-deftest test-pearl-issue-source-round-trips-through-header ()
+  "The issue source survives `#+LINEAR-SOURCE' serialization and read-back."
+  (let* ((s (pearl--issue-source "u1" "ENG-7"))
+         (back (car (read-from-string (pearl--linear-source-string s)))))
+    (should (equal s back))))
+
+;;; pearl--fetch-and-render-issue
+
+(ert-deftest test-pearl-fetch-and-render-issue-renders-one ()
+  "A fetched node renders through the shared query-result boundary as one issue,
+tagged with an issue source built from the node's own id and identifier."
+  (let ((node '((id . "u1") (identifier . "ENG-7") (title . "A bug")))
+        captured)
+    (cl-letf (((symbol-function 'pearl--fetch-issue-async)
+               (lambda (_ref cb) (funcall cb node)))
+              ((symbol-function 'pearl--render-query-result)
+               (lambda (result source) (setq captured (list result source)))))
+      (pearl--fetch-and-render-issue "ENG-7")
+      (should captured)
+      (let ((result (nth 0 captured))
+            (source (nth 1 captured)))
+        (should (equal (list node) (pearl--query-result-issues result)))
+        (should (eq 'issue (plist-get source :type)))
+        (should (string= "u1" (plist-get source :id)))
+        (should (string= "ENG-7" (plist-get source :identifier)))))))
+
+(ert-deftest test-pearl-fetch-and-render-issue-missing-does-not-render ()
+  "A `:missing' result reports and renders nothing (no buffer rewrite)."
+  (let (rendered)
+    (cl-letf (((symbol-function 'pearl--fetch-issue-async)
+               (lambda (_ref cb) (funcall cb :missing)))
+              ((symbol-function 'pearl--render-query-result)
+               (lambda (&rest _) (setq rendered t)))
+              ((symbol-function 'message) (lambda (&rest _) nil)))
+      (pearl--fetch-and-render-issue "ENG-404")
+      (should-not rendered))))
+
+(ert-deftest test-pearl-fetch-and-render-issue-error-does-not-render ()
+  "An `:error' result reports and renders nothing."
+  (let (rendered)
+    (cl-letf (((symbol-function 'pearl--fetch-issue-async)
+               (lambda (_ref cb) (funcall cb :error)))
+              ((symbol-function 'pearl--render-query-result)
+               (lambda (&rest _) (setq rendered t)))
+              ((symbol-function 'message) (lambda (&rest _) nil)))
+      (pearl--fetch-and-render-issue "ENG-7")
+      (should-not rendered))))
+
+;;; pearl-open-issue-by-id
+
+(ert-deftest test-pearl-open-issue-by-id-forwards-trimmed-ref ()
+  "The command trims the typed ref and forwards it to the fetch/render path."
+  (let (got)
+    (cl-letf (((symbol-function 'pearl--require-account-context) #'ignore)
+              ((symbol-function 'pearl--progress) (lambda (&rest _) nil))
+              ((symbol-function 'pearl--fetch-and-render-issue)
+               (lambda (ref) (setq got ref))))
+      (pearl-open-issue-by-id "  ENG-7  ")
+      (should (string= "ENG-7" got)))))
+
+(ert-deftest test-pearl-open-issue-by-id-rejects-empty ()
+  "An empty/whitespace identifier is a `user-error', not a fetch."
+  (let (fetched)
+    (cl-letf (((symbol-function 'pearl--require-account-context) #'ignore)
+              ((symbol-function 'pearl--fetch-and-render-issue)
+               (lambda (&rest _) (setq fetched t))))
+      (should-error (pearl-open-issue-by-id "   ") :type 'user-error)
+      (should-not fetched))))
+
+(provide 'test-pearl-single-issue)
+;;; test-pearl-single-issue.el ends here