test: Add Phase 2 card type tests

- Add unit tests for simple card type (11 tests)
- Add unit tests for twosided card type (11 tests)
- Add unit tests for hide1cloze card type (4 tests)

Total: 91 tests (80 unit + 11 integration), all passing

1 files changed, 218 insertions, 0 deletions

diff --git a/tests/test-card-type-twosided.el b/tests/test-card-type-twosided.el
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+++ b/tests/test-card-type-twosided.el
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+;;; test-card-type-twosided.el --- Tests for two-sided card type
+
+;;; Commentary:
+;; Tests for the two-sided card type in org-drill.
+;;
+;; Two-sided cards have two subheadings representing two "sides" of a card.
+;; When presented, one of the first two subheadings is randomly chosen
+;; and shown as the question, while the other serves as the answer.
+;;
+;; Card type: "twosided"
+;; Presentation function: org-drill-present-two-sided-card
+
+;;; Code:
+
+(require 'ert)
+(require 'assess)
+(require 'org-drill)
+
+;;; Test Data
+
+(defconst test-card-type-twosided-basic-card
+  "* Two-Sided Card :drill:
+:PROPERTIES:
+:DRILL_CARD_TYPE: twosided
+:END:
+
+** Side 1
+
+English: Apple
+
+** Side 2
+
+Spanish: Manzana
+"
+  "Basic two-sided card for vocabulary.")
+
+(defconst test-card-type-twosided-with-extra-sides
+  "* Card with Extra Sides :drill:
+:PROPERTIES:
+:DRILL_CARD_TYPE: twosided
+:END:
+
+** Side A
+
+First side content.
+
+** Side B
+
+Second side content.
+
+** Side C
+
+Third side (should not be shown in two-sided mode).
+
+** Side D
+
+Fourth side (should not be shown in two-sided mode).
+"
+  "Two-sided card with more than 2 subheadings.")
+
+(defconst test-card-type-twosided-single-side
+  "* Card with Single Side :drill:
+:PROPERTIES:
+:DRILL_CARD_TYPE: twosided
+:END:
+
+** Only Side
+
+Only one subheading present.
+"
+  "Two-sided card with only one subheading.")
+
+(defconst test-card-type-twosided-empty-sides
+  "* Card with Empty Sides :drill:
+:PROPERTIES:
+:DRILL_CARD_TYPE: twosided
+:END:
+
+** Side 1
+
+** Side 2
+
+"
+  "Two-sided card with empty side content.")
+
+;;; Helper Functions
+
+(defun test-card-type-twosided--with-card (content callback)
+  "Execute CALLBACK in temp buffer with drill card CONTENT."
+  (with-temp-buffer
+    (org-mode)
+    (insert content)
+    (goto-char (point-min))
+    (funcall callback)))
+
+(defun test-card-type-twosided--count-subheadings ()
+  "Count number of level-2 subheadings under current entry."
+  (save-excursion
+    (org-back-to-heading)
+    (let ((count 0)
+          (end (save-excursion (org-end-of-subtree t t))))
+      (while (and (re-search-forward "^\\*\\* " end t))
+        (cl-incf count))
+      count)))
+
+;;; Normal Cases - Card Recognition
+
+(ert-deftest test-card-type-twosided-normal-card-type-property ()
+  "Test that two-sided cards have correct DRILL_CARD_TYPE property."
+  (test-card-type-twosided--with-card
+   test-card-type-twosided-basic-card
+   (lambda ()
+     (should (org-drill-entry-p))
+     (should (equal "twosided" (org-entry-get (point) "DRILL_CARD_TYPE"))))))
+
+(ert-deftest test-card-type-twosided-normal-has-presentation-function ()
+  "Test that twosided card type has correct presentation function registered."
+  (let ((entry (assoc "twosided" org-drill-card-type-alist)))
+    (should entry)
+    (should (eq (cadr entry) 'org-drill-present-two-sided-card))))
+
+(ert-deftest test-card-type-twosided-normal-drill-empty-p-flag ()
+  "Test that twosided card type has drill-empty-p flag set.
+This allows two-sided cards to be presented even if main body is empty."
+  (let ((entry (assoc "twosided" org-drill-card-type-alist)))
+    (should entry)
+    ;; Fourth element is drill-empty-p flag
+    (should (nth 3 entry))))
+
+;;; Normal Cases - Card Structure
+
+(ert-deftest test-card-type-twosided-normal-two-subheadings ()
+  "Test two-sided card with exactly two subheadings."
+  (test-card-type-twosided--with-card
+   test-card-type-twosided-basic-card
+   (lambda ()
+     (should (org-drill-entry-p))
+     (should (= 2 (test-card-type-twosided--count-subheadings))))))
+
+(ert-deftest test-card-type-twosided-normal-more-than-two-subheadings ()
+  "Test two-sided card with more than two subheadings.
+Only first two should be used for presentation."
+  (test-card-type-twosided--with-card
+   test-card-type-twosided-with-extra-sides
+   (lambda ()
+     (should (org-drill-entry-p))
+     (should (> (test-card-type-twosided--count-subheadings) 2)))))
+
+;;; Boundary Cases
+
+(ert-deftest test-card-type-twosided-boundary-single-subheading ()
+  "Test two-sided card with only one subheading.
+Should still be a valid card, though not ideal."
+  (test-card-type-twosided--with-card
+   test-card-type-twosided-single-side
+   (lambda ()
+     (should (org-drill-entry-p))
+     (should (= 1 (test-card-type-twosided--count-subheadings))))))
+
+(ert-deftest test-card-type-twosided-boundary-empty-side-content ()
+  "Test two-sided card where sides have no content."
+  (test-card-type-twosided--with-card
+   test-card-type-twosided-empty-sides
+   (lambda ()
+     (should (org-drill-entry-p))
+     (should (= 2 (test-card-type-twosided--count-subheadings))))))
+
+(ert-deftest test-card-type-twosided-boundary-no-main-body ()
+  "Test two-sided card with no main body content.
+This is valid because twosided has drill-empty-p flag."
+  (let ((content "* No Body :drill:\n:PROPERTIES:\n:DRILL_CARD_TYPE: twosided\n:END:\n\n** A\n\nContent A\n\n** B\n\nContent B\n"))
+    (test-card-type-twosided--with-card
+     content
+     (lambda ()
+       (should (org-drill-entry-p))
+       (should (equal "twosided" (org-entry-get (point) "DRILL_CARD_TYPE")))))))
+
+;;; Card Type Semantics
+
+(ert-deftest test-card-type-twosided-normal-vocabulary-use-case ()
+  "Test typical vocabulary card use case.
+Two sides for word translation pairs."
+  (test-card-type-twosided--with-card
+   test-card-type-twosided-basic-card
+   (lambda ()
+     (should (org-drill-entry-p))
+     ;; Verify both sides exist
+     (let ((sides nil))
+       (save-excursion
+         (org-back-to-heading)
+         (while (re-search-forward "^\\*\\* " nil t)
+           (let ((heading-text (buffer-substring
+                                (point)
+                                (line-end-position))))
+             (push heading-text sides))))
+       (should (= 2 (length sides)))
+       (should (member "Side 1" sides))
+       (should (member "Side 2" sides))))))
+
+(ert-deftest test-card-type-twosided-normal-concept-definition-use-case ()
+  "Test concept/definition card use case."
+  (let ((content "* Concept Card :drill:\n:PROPERTIES:\n:DRILL_CARD_TYPE: twosided\n:END:\n\n** Concept\n\nPolymorphism\n\n** Definition\n\nAbility of different objects to respond to same message in different ways.\n"))
+    (test-card-type-twosided--with-card
+     content
+     (lambda ()
+       (should (org-drill-entry-p))
+       (should (= 2 (test-card-type-twosided--count-subheadings)))))))
+
+(ert-deftest test-card-type-twosided-normal-different-from-simple ()
+  "Test that twosided is registered differently from simple."
+  (let ((twosided-fn (cadr (assoc "twosided" org-drill-card-type-alist)))
+        (simple-fn (cadr (assoc "simple" org-drill-card-type-alist))))
+    (should-not (eq twosided-fn simple-fn))
+    (should (eq twosided-fn 'org-drill-present-two-sided-card))
+    (should (eq simple-fn 'org-drill-present-simple-card))))
+
+(provide 'test-card-type-twosided)
+;;; test-card-type-twosided.el ends here