fix: japanese characters not truncated correctly in tui terminal output

3 files changed, 55 insertions, 0 deletions

diff --git a/app/tests/test_runview.py b/app/tests/test_runview.py
index 8feeee1..3f77ed0 100644
--- a/app/tests/test_runview.py
+++ b/app/tests/test_runview.py
@@ -62,10 +62,21 @@ class FormatTests(_FakeTui, unittest.TestCase):
         self.assertEqual(runview._fit("hello", 3), "he~")
         self.assertEqual(runview._fit("hi", 10), "hi")
 
+    def test_fit_truncates_wide_characters_by_display_columns(self):
+        # Japanese characters fill two terminal cells each, so fitting
+        # by character count would let lines overflow their pane.
+        self.assertEqual(runview._fit("你好", 4), "你好")
+        self.assertEqual(runview._fit("你好你好", 5), "你好~")
+        self.assertEqual(runview._fit("こんにちは", 3), "こ~")
+
     def test_wrap_wraps_on_word_boundaries(self):
         self.assertEqual(runview._wrap("aaaa bbbb cccc dddd", 12),
                          ["aaaa bbbb", "cccc dddd"])
 
+    def test_wrap_counts_wide_characters_as_two_columns(self):
+        self.assertEqual(runview._wrap("日本語 テスト", 10),
+                         ["日本語", "テスト"])
+
 
 class StateTransitionTests(_FakeTui, unittest.TestCase):
     def test_boot_flow_starting_to_ready(self):
diff --git a/app/tests/test_taskview.py b/app/tests/test_taskview.py
index 1db708d..78cc2f1 100644
--- a/app/tests/test_taskview.py
+++ b/app/tests/test_taskview.py
@@ -725,6 +725,25 @@ class LanesViewTests(_FakeTui, unittest.TestCase):
         pane_w = (screen.width - 3) // 2
         self.assertLessEqual(x + len(label) - 1, 1 + pane_w - 2)
 
+    def test_split_render_truncates_wide_log_lines_to_their_pane(self):
+        # Regression: Japanese characters fill two terminal cells each,
+        # so fitting by character count let transcription results spill
+        # out of the right pane onto the left one.
+        view, screen = self.make_view(self._two_lanes(), width=80)
+        view._ingest_lane_line(view._lanes[1],
+                               "[OK] 一号: " + "語" * 40)
+        view.render()
+        found = [(x, t) for _, x, t, _ in screen.strings
+                 if t.startswith("[OK] ")]
+        self.assertEqual(len(found), 1)
+        x, line = found[0]
+        self.assertTrue(line.endswith("~"))
+        pane_w = (screen.width - 3) // 2
+        px, pw = 1 + pane_w + 1, (screen.width - 3) - pane_w
+        self.assertGreaterEqual(x, px + 1)
+        self.assertLessEqual(x + taskview.tui._disp_width(line) - 1,
+                             px + pw - 2)
+
 
 class SilenceCueTests(_FakeTui, unittest.TestCase):
     """The "(no output 6m)" cue for a running step that stopped emitting."""
diff --git a/app/tests/test_tui.py b/app/tests/test_tui.py
index 6fc3fd5..4c8b431 100644
--- a/app/tests/test_tui.py
+++ b/app/tests/test_tui.py
@@ -1501,6 +1501,31 @@ class TextViewerTests(TuiTestCase):
         self.assertTrue(drawn[0].endswith("~"))
 
 
+class FitTests(TuiTestCase):
+    """Column-aware fitting: East Asian Wide characters occupy 2 cells."""
+
+    def test_disp_width_counts_wide_characters_twice(self):
+        self.assertEqual(tui._disp_width(""), 0)
+        self.assertEqual(tui._disp_width("hello"), 5)
+        self.assertEqual(tui._disp_width("一号"), 4)
+        self.assertEqual(tui._disp_width("mix語end"), 8)
+
+    def test_fit_truncates_by_display_columns(self):
+        self.assertEqual(tui._fit("hello", 3), "he~")
+        self.assertEqual(tui._fit("hi", 10), "hi")
+        # Exact fit keeps the wide pair; one column more would overflow.
+        self.assertEqual(tui._fit("你好", 4), "你好")
+        self.assertEqual(tui._fit("你好你好", 5), "你好~")
+        self.assertEqual(tui._fit("こんにちは", 3), "こ~")
+
+    def test_wrap_segments_counts_wide_characters_twice(self):
+        # "語 語 語" is 8 cells, so at width 5 only two words fit per
+        # line even though 5 characters would fit by count.
+        lines = tui._wrap_segments([("語 語 語", None)], 5)
+        self.assertEqual(["".join(t for t, _ in line) for line in lines],
+                         ["語 語", "語"])
+
+
 class WizardTests(unittest.TestCase):
     """The tui.Wizard screen-stack driver: Esc steps back one screen."""