2 files changed, 64 insertions, 9 deletions

diff --git a/cli/js/tests/console_test.ts b/cli/js/tests/console_test.ts
index 264987ba9..a49cd95ca 100644
--- a/cli/js/tests/console_test.ts
+++ b/cli/js/tests/console_test.ts
@@ -1045,6 +1045,20 @@ unitTest(function consoleTable(): void {
     console.table("test");
     assertEquals(out.toString(), "test\n");
   });
+  mockConsole((console, out): void => {
+    console.table(["Hello", "你好", "Amapá"]);
+    assertEquals(
+      out.toString(),
+      `┌─────────┬─────────┐
+│ (index) │ Values  │
+├─────────┼─────────┤
+│    0    │ "Hello" │
+│    1    │ "你好"  │
+│    2    │ "Amapá" │
+└─────────┴─────────┘
+`
+    );
+  });
 });
 
 // console.log(Error) test
diff --git a/cli/js/web/console_table.ts b/cli/js/web/console_table.ts
index 2cb0005d7..dc22433af 100644
--- a/cli/js/web/console_table.ts
+++ b/cli/js/web/console_table.ts
@@ -1,11 +1,8 @@
 // Copyright Joyent, Inc. and other Node contributors. MIT license.
 // Forked from Node's lib/internal/cli_table.js
 
-import { TextEncoder } from "./text_encoding.ts";
 import { hasOwnProperty } from "./util.ts";
 
-const encoder = new TextEncoder();
-
 const tableChars = {
   middleMiddle: "─",
   rowMiddle: "┼",
@@ -28,17 +25,61 @@ function removeColors(str: string): string {
   return str.replace(colorRegExp, "");
 }
 
-function countBytes(str: string): number {
-  const normalized = removeColors(String(str)).normalize("NFC");
+function isFullWidthCodePoint(code: number): boolean {
+  // Code points are partially derived from:
+  // http://www.unicode.org/Public/UNIDATA/EastAsianWidth.txt
+  return (
+    code >= 0x1100 &&
+    (code <= 0x115f || // Hangul Jamo
+    code === 0x2329 || // LEFT-POINTING ANGLE BRACKET
+    code === 0x232a || // RIGHT-POINTING ANGLE BRACKET
+      // CJK Radicals Supplement .. Enclosed CJK Letters and Months
+      (code >= 0x2e80 && code <= 0x3247 && code !== 0x303f) ||
+      // Enclosed CJK Letters and Months .. CJK Unified Ideographs Extension A
+      (code >= 0x3250 && code <= 0x4dbf) ||
+      // CJK Unified Ideographs .. Yi Radicals
+      (code >= 0x4e00 && code <= 0xa4c6) ||
+      // Hangul Jamo Extended-A
+      (code >= 0xa960 && code <= 0xa97c) ||
+      // Hangul Syllables
+      (code >= 0xac00 && code <= 0xd7a3) ||
+      // CJK Compatibility Ideographs
+      (code >= 0xf900 && code <= 0xfaff) ||
+      // Vertical Forms
+      (code >= 0xfe10 && code <= 0xfe19) ||
+      // CJK Compatibility Forms .. Small Form Variants
+      (code >= 0xfe30 && code <= 0xfe6b) ||
+      // Halfwidth and Fullwidth Forms
+      (code >= 0xff01 && code <= 0xff60) ||
+      (code >= 0xffe0 && code <= 0xffe6) ||
+      // Kana Supplement
+      (code >= 0x1b000 && code <= 0x1b001) ||
+      // Enclosed Ideographic Supplement
+      (code >= 0x1f200 && code <= 0x1f251) ||
+      // Miscellaneous Symbols and Pictographs 0x1f300 - 0x1f5ff
+      // Emoticons 0x1f600 - 0x1f64f
+      (code >= 0x1f300 && code <= 0x1f64f) ||
+      // CJK Unified Ideographs Extension B .. Tertiary Ideographic Plane
+      (code >= 0x20000 && code <= 0x3fffd))
+  );
+}
+
+function getStringWidth(str: string): number {
+  str = removeColors(str).normalize("NFC");
+  let width = 0;
+
+  for (const ch of str) {
+    width += isFullWidthCodePoint(ch.codePointAt(0)!) ? 2 : 1;
+  }
 
-  return encoder.encode(normalized).byteLength;
+  return width;
 }
 
 function renderRow(row: string[], columnWidths: number[]): string {
   let out = tableChars.left;
   for (let i = 0; i < row.length; i++) {
     const cell = row[i];
-    const len = countBytes(cell);
+    const len = getStringWidth(cell);
     const needed = (columnWidths[i] - len) / 2;
     // round(needed) + ceil(needed) will always add up to the amount
     // of spaces we need while also left justifying the output.
@@ -53,7 +94,7 @@ function renderRow(row: string[], columnWidths: number[]): string {
 
 export function cliTable(head: string[], columns: string[][]): string {
   const rows: string[][] = [];
-  const columnWidths = head.map((h: string): number => countBytes(h));
+  const columnWidths = head.map((h: string): number => getStringWidth(h));
   const longestColumn = columns.reduce(
     (n: number, a: string[]): number => Math.max(n, a.length),
     0
@@ -67,7 +108,7 @@ export function cliTable(head: string[], columns: string[][]): string {
       }
       const value = (rows[j][i] = hasOwnProperty(column, j) ? column[j] : "");
       const width = columnWidths[i] || 0;
-      const counted = countBytes(value);
+      const counted = getStringWidth(value);
       columnWidths[i] = Math.max(width, counted);
     }
   }