From 52d77652d00cd4df41875b5e518925c5839fc862 Mon Sep 17 00:00:00 2001
From: Bill Rossi <bassguitarbill@gmail.com>
Date: Sat, 16 Aug 2025 09:22:23 -0400
Subject: [PATCH] Past tense

---
 lib/verb.rb       | 20 ++++++++++++++++++++
 test/test_verb.rb | 44 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 64 insertions(+)

diff --git a/lib/verb.rb b/lib/verb.rb
index b121cab..9d82d6d 100644
--- a/lib/verb.rb
+++ b/lib/verb.rb
@@ -10,6 +10,10 @@ U_VOWEL_CHANGES = {
   "ぬ" => { "a" => "な", "i" => "に", "u" => "ぬ", "e" => "ね", "o" => "の" },
 }
 
+TE_TA_DE_DA = {
+  "て" => "た", "で" => "だ"
+}
+
 class KanaKanji
   attr_reader :kana, :kanji
   def initialize(kana, kanji=nil)
@@ -69,9 +73,25 @@ class Verb
     stem + "ません"
   end
 
+  def long_form_past_positive
+    stem + "ました"
+  end
+
+  def long_form_past_negative
+    long_form_present_negative + "でした"
+  end
+
   def short_form_present_positive
     dictionary
   end
+
+  def short_form_past_positive
+    te.all_but_last_character + TE_TA_DE_DA[te.last_character]
+  end
+
+  def short_form_past_negative
+    short_form_present_negative.all_but_last_character + "かった"
+  end
 end
 
 class IchidanVerb < Verb
diff --git a/test/test_verb.rb b/test/test_verb.rb
index 1509a13..be63fe1 100644
--- a/test/test_verb.rb
+++ b/test/test_verb.rb
@@ -83,4 +83,48 @@ class TestVerb < Minitest::Test
     assert_equal "勉強しない", @benkyousuru.short_form_present_negative.kanji
     assert_equal "べんきょうしない", @benkyousuru.short_form_present_negative.kana
   end
+
+  def test_long_form_past_positive
+    assert_equal "見ました", @miru.long_form_past_positive.kanji
+    assert_equal "みました", @miru.long_form_past_positive.kana
+    assert_equal "飲みました", @nomu.long_form_past_positive.kanji
+    assert_equal "のみました", @nomu.long_form_past_positive.kana
+    assert_equal "しました", @suru.long_form_past_positive.kanji
+    assert_equal "しました", @suru.long_form_past_positive.kana
+    assert_equal "勉強しました", @benkyousuru.long_form_past_positive.kanji
+    assert_equal "べんきょうしました", @benkyousuru.long_form_past_positive.kana
+  end
+
+  def test_long_form_past_negative
+    assert_equal "見ませんでした", @miru.long_form_past_negative.kanji
+    assert_equal "みませんでした", @miru.long_form_past_negative.kana
+    assert_equal "飲みませんでした", @nomu.long_form_past_negative.kanji
+    assert_equal "のみませんでした", @nomu.long_form_past_negative.kana
+    assert_equal "しませんでした", @suru.long_form_past_negative.kanji
+    assert_equal "しませんでした", @suru.long_form_past_negative.kana
+    assert_equal "勉強しませんでした", @benkyousuru.long_form_past_negative.kanji
+    assert_equal "べんきょうしませんでした", @benkyousuru.long_form_past_negative.kana
+  end
+
+  def test_short_form_past_positive
+    assert_equal "見た", @miru.short_form_past_positive.kanji
+    assert_equal "みた", @miru.short_form_past_positive.kana
+    assert_equal "飲んだ", @nomu.short_form_past_positive.kanji
+    assert_equal "のんだ", @nomu.short_form_past_positive.kana
+    assert_equal "した", @suru.short_form_past_positive.kanji
+    assert_equal "した", @suru.short_form_past_positive.kana
+    assert_equal "勉強した", @benkyousuru.short_form_past_positive.kanji
+    assert_equal "べんきょうした", @benkyousuru.short_form_past_positive.kana
+  end
+
+  def test_short_form_past_negative
+    assert_equal "見なかった", @miru.short_form_past_negative.kanji
+    assert_equal "みなかった", @miru.short_form_past_negative.kana
+    assert_equal "飲まなかった", @nomu.short_form_past_negative.kanji
+    assert_equal "のまなかった", @nomu.short_form_past_negative.kana
+    assert_equal "しなかった", @suru.short_form_past_negative.kanji
+    assert_equal "しなかった", @suru.short_form_past_negative.kana
+    assert_equal "勉強しなかった", @benkyousuru.short_form_past_negative.kanji
+    assert_equal "べんきょうしなかった", @benkyousuru.short_form_past_negative.kana
+  end
 end