From f7c9adacdc5682fdce74099a827d5e1f29ec9ec2 Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Tue, 8 Sep 2026 10:20:36 -0700
Subject: [PATCH] fix(terminal): keep wrapped multiline cells aligned (#142305)

---
 packages/terminal-core/src/table.test.ts | 14 +++++++-------
 packages/terminal-core/src/table.ts      |  9 +++++++--
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/packages/terminal-core/src/table.test.ts b/packages/terminal-core/src/table.test.ts
index 18ca1456f492..6cf07e5b54d5 100644
--- a/packages/terminal-core/src/table.test.ts
+++ b/packages/terminal-core/src/table.test.ts
@@ -626,18 +626,18 @@ console.log(JSON.stringify({
     ["colored CRLF", "\r\n", "\x1b[31m", "\x1b[39m"],
     ["linked LF", "\n", "\x1b]8;;https://example.com/\x07", "\x1b]8;;\x07"],
   ])(
-    "preserves blank %s lines at their positions across cells",
+    "preserves blank %s lines without adding rows after wrapped spacing",
     (_label, separator, open, close) => {
       const out = renderTable({
         border: "ascii",
-        width: 30,
+        width: 15,
         columns: [
-          { key: "A", header: "A", flex: true },
-          { key: "B", header: "B", flex: true },
+          { key: "A", header: "A", minWidth: 6, maxWidth: 6 },
+          { key: "B", header: "B", minWidth: 6, maxWidth: 6 },
         ],
         rows: [
           {
-            A: `${open}${["", "alpha", "", "omega", "", ""].join(separator)}${close}`,
+            A: `${open}${["", "Read ", "", "Next", "", ""].join(separator)}${close}`,
             B: "0\n1\n2\n3\n4",
           },
         ],
@@ -653,9 +653,9 @@ console.log(JSON.stringify({
         ),
       ).toEqual([
         ["", "0"],
-        ["alpha", "1"],
+        ["Read", "1"],
         ["", "2"],
-        ["omega", "3"],
+        ["Next", "3"],
         ["", "4"],
       ]);
       if (open) {
diff --git a/packages/terminal-core/src/table.ts b/packages/terminal-core/src/table.ts
index ae452b5f91b2..adf441f9798f 100644
--- a/packages/terminal-core/src/table.ts
+++ b/packages/terminal-core/src/table.ts
@@ -251,12 +251,13 @@ function wrapLine(text: string, width: number): string[] {
     ch === " " || ch === "/" || ch === "-" || ch === "_" || ch === ".";
   let skipNextLf = false;
   let hasChar = false;
+  let logicalLineHasOutput = false;
 
   const buf: AnsiToken[] = [];
   let bufVisible = 0;
   let lastBreakIndex: number | null = null;
 
-  // Explicit newlines emit empty buffers too, keeping sibling cell rows aligned.
+  // A soft wrap can empty the buffer before a newline without creating a blank logical line.
   const flushAt = (breakAt: number | null) => {
     // Keep the suffix in its buffer: long zero-width runs can exceed the argument
     // limit of a spread-based copy even when their visible width is small.
@@ -286,7 +287,10 @@ function wrapLine(text: string, width: number): string[] {
     const openOsc8 = activeOsc8 ? `${ESC}]8;${activeOsc8.params};${activeOsc8.uri}${BEL}` : "";
     const closeSgr = activeSgr.map((state) => state.close).join("");
 
-    lines.push(`${content.join("")}${closeOsc8}${closeSgr}`.trimEnd());
+    if (bufVisible > 0 || !logicalLineHasOutput) {
+      lines.push(`${content.join("")}${closeOsc8}${closeSgr}`.trimEnd());
+      logicalLineHasOutput = true;
+    }
     if (breakAt == null || breakAt <= 0) {
       buf.length = 0;
       if (openOsc8) {
@@ -331,6 +335,7 @@ function wrapLine(text: string, width: number): string[] {
       if (ch === "\n" || ch === "\r" || ch === "\r\n") {
         skipNextLf = ch === "\r";
         flushAt(buf.length);
+        logicalLineHasOutput = false;
         return;
       }
       // Soft-wrap remainders reuse the width measured when each token entered the buffer.