From 94a197703b348b4351a15df4ae6d436de45ef5af Mon Sep 17 00:00:00 2001
From: sujipar <bagsuji264@gmail.com>
Date: Tue, 27 Oct 2026 19:42:53 +0900
Subject: [PATCH] fix: wrap by display width so full-width text is not dropped
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textWrap() compared line.length against maxLength, which is a display width, and sliced
by code units. A line of full-width characters is twice as wide as its length, so the
function emitted lines wider than the cell; truncate() then cut the overflow and replaced
it with an ellipsis, so the characters were lost from the output entirely.

With colWidths: [14], wordWrap: true, wrapOnWordBoundary: false, a 14-character Korean
string came back as 7 characters. The same options preserve all 24 characters of an ASCII
string, so the loss was specific to wide text.

Measure with strlen() and slice with truncateWidth() — both already in this file, which
already imports string-width. ASCII takes truncateWidth's fast path and is unchanged.

The guard for an empty head is new: truncateWidth() returns  when even one character is
too wide for the budget (a full-width character in a single column), which would stop the
loop from making progress.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
---
 src/utils.js       |  9 ++++++---
 test/table-test.js | 20 ++++++++++++++++++++
 test/utils-test.js | 13 +++++++++++++
 3 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/src/utils.js b/src/utils.js
index 0f7de6c..8e6fe4b 100644
--- a/src/utils.js
+++ b/src/utils.js
@@ -286,9 +286,12 @@ function textWrap(maxLength, input) {
   function pushLine(str, ws) {
     if (line.length && ws) line += ws;
     line += str;
-    while (line.length > maxLength) {
-      lines.push(line.slice(0, maxLength));
-      line = line.slice(maxLength);
+    while (strlen(line) > maxLength) {
+      let head = truncateWidth(line, maxLength);
+      // a full-width char cannot fit in a single column, take it anyway so the loop makes progress
+      if (!head.length) head = line.slice(0, 1);
+      lines.push(head);
+      line = line.slice(head.length);
     }
   }
   let split = input.split(/(\s+)/g);
diff --git a/test/table-test.js b/test/table-test.js
index 6bd4e8e..33324a3 100644
--- a/test/table-test.js
+++ b/test/table-test.js
@@ -19,6 +19,26 @@ describe('@api Table ', function () {
     expect(table.toString()).toEqual(expected.join('\n'));
   });
 
+  it('wordWrap without word boundaries does not drop full-width chars', function () {
+    let table = new Table({ colWidths: [14], wordWrap: true, wrapOnWordBoundary: false });
+
+    table.push(['가나다라마바사아자차카타파하']);
+
+    let expected = ['┌──────────────┐', '│ 가나다라마바 │', '│ 사아자차카타 │', '│ 파하         │', '└──────────────┘'];
+
+    expect(table.toString()).toEqual(expected.join('\n'));
+  });
+
+  it('wordWrap without word boundaries keeps ascii behaviour', function () {
+    let table = new Table({ colWidths: [14], wordWrap: true, wrapOnWordBoundary: false });
+
+    table.push(['abcdefghijklmnopqrstuvwx']);
+
+    let expected = ['┌──────────────┐', '│ abcdefghijkl │', '│ mnopqrstuvwx │', '└──────────────┘'];
+
+    expect(table.toString()).toEqual(expected.join('\n'));
+  });
+
   it('allows numbers as `content` property of cells defined using object notation', function () {
     let table = new Table({ style: { border: [], head: [] } });
 
diff --git a/test/utils-test.js b/test/utils-test.js
index 6c02cac..218a15e 100644
--- a/test/utils-test.js
+++ b/test/utils-test.js
@@ -333,6 +333,19 @@ describe('utils', function () {
           'stuv wx yz',
         ]);
       });
+
+      it('wraps long full-width words by display width', function () {
+        // 12 columns fit 6 full-width chars, not 12
+        expect(wordWrap(12, '가나다라마바사아자차카타파하', false)).toEqual(['가나다라마바', '사아자차카타', '파하']);
+        expect(wordWrap(12, '这是一段没有空格的中文', false)).toEqual(['这是一段没有', '空格的中文']);
+      });
+
+      it('never returns a line wider than maxLength', function () {
+        let lines = wordWrap(12, '가나다라마바사아자차카타파하', false);
+        lines.forEach(function (line) {
+          expect(strlen(line)).toBeLessThanOrEqual(12);
+        });
+      });
     });
   });