test: add gloss-display test suite (red phase)

Four test files covering the gloss-display public API and pure helpers.
All 23 tests fail at this commit because the implementation is still a
stub. Format-candidate gets full N/B/E coverage. Render-entry gets the
pure-helper treatment. Pick-definition mocks completing-read at the
boundary. Show-entry has a single smoke test.

1 files changed, 64 insertions, 0 deletions

diff --git a/tests/test-gloss-display--render-entry.el b/tests/test-gloss-display--render-entry.el
new file mode 100644
index 0000000..5656660
--- /dev/null
+++ b/tests/test-gloss-display--render-entry.el
@@ -0,0 +1,64 @@
+;;; test-gloss-display--render-entry.el --- Tests for gloss-display--render-entry -*- lexical-binding: t -*-
+
+;; SPDX-License-Identifier: GPL-3.0-or-later
+
+;;; Commentary:
+;; Tests for the pure helper `gloss-display--render-entry' covering
+;; Normal/Boundary/Error cases.  The helper takes a TERM and BODY and
+;; returns the formatted string that `gloss-display-show-entry' inserts
+;; into the side buffer.
+
+;;; Code:
+
+(require 'ert)
+(require 'gloss-display)
+
+(ert-deftest test-gloss-display-render-entry-normal-term-and-body ()
+  "Normal: render produces the term, an underline, a blank, and the body."
+  (let ((result (gloss-display--render-entry
+                 "anaphora"
+                 "Reference to something earlier in the discourse.")))
+    (should (string-match-p "^anaphora\n" result))
+    (should (string-match-p "^=+\n" (substring result (length "anaphora\n"))))
+    (should (string-match-p "Reference to something earlier" result))))
+
+(ert-deftest test-gloss-display-render-entry-normal-underline-matches-term-length ()
+  "Normal: the underline length matches the term length."
+  (let* ((term "abc")
+         (result (gloss-display--render-entry term "Body."))
+         (lines (split-string result "\n")))
+    (should (equal (nth 0 lines) term))
+    (should (= (length (nth 1 lines)) (length term)))
+    (should (string-match-p "^=+$" (nth 1 lines)))))
+
+(ert-deftest test-gloss-display-render-entry-boundary-multi-line-body ()
+  "Boundary: a multi-line body is preserved verbatim."
+  (let ((result (gloss-display--render-entry
+                 "term"
+                 "First paragraph.\n\nSecond paragraph.")))
+    (should (string-match-p "First paragraph\\." result))
+    (should (string-match-p "Second paragraph\\." result))
+    (should (string-match-p "First paragraph\\.\n\nSecond paragraph\\." result))))
+
+(ert-deftest test-gloss-display-render-entry-boundary-empty-body ()
+  "Boundary: an empty body still renders the term and underline."
+  (let ((result (gloss-display--render-entry "lonely" "")))
+    (should (string-match-p "^lonely\n=+\n" result))))
+
+(ert-deftest test-gloss-display-render-entry-boundary-unicode-term ()
+  "Boundary: unicode characters in the term are preserved."
+  (let* ((term "café")
+         (result (gloss-display--render-entry term "A coffeehouse.")))
+    (should (string-match-p (regexp-quote term) result))
+    (should (string-match-p "A coffeehouse\\." result))))
+
+(ert-deftest test-gloss-display-render-entry-boundary-very-long-term ()
+  "Boundary: a long term gets a matching long underline."
+  (let* ((term (make-string 60 ?z))
+         (result (gloss-display--render-entry term "Body."))
+         (lines (split-string result "\n")))
+    (should (equal (nth 0 lines) term))
+    (should (= (length (nth 1 lines)) 60))))
+
+(provide 'test-gloss-display--render-entry)
+;;; test-gloss-display--render-entry.el ends here