From 95b7dc36e7219e94ada3dd4dd751cc3221e9b0e3 Mon Sep 17 00:00:00 2001
From: robobun <117481402+robobun@users.noreply.github.com>
Date: Sun, 16 Aug 2026 01:43:09 +0000
Subject: [PATCH] shell: accept seq --separator=X and --terminator=X

The seq builtin only matched the long options spelled as a separate
argument (--separator X), so the --separator=X spelling fell through to
operand parsing and failed with "seq: invalid argument". Take the value
after the = in the same arm that handles the attached -sX / -tX forms.
---
 src/runtime/shell/builtin/seq.rs       | 14 +++++---
 test/js/bun/shell/commands/seq.test.ts | 48 ++++++++++++++++++++++++++
 2 files changed, 58 insertions(+), 4 deletions(-)

diff --git a/src/runtime/shell/builtin/seq.rs b/src/runtime/shell/builtin/seq.rs
index fbad2252f12f..979977edffe9 100644
--- a/src/runtime/shell/builtin/seq.rs
+++ b/src/runtime/shell/builtin/seq.rs
@@ -60,8 +60,11 @@ impl Seq {
                 idx += 1;
                 continue;
             }
-            if arg.starts_with(b"-s") && arg.len() > 2 {
-                Self::state_mut(interp, cmd).separator = bun_ptr::RawSlice::new(&arg[2..]);
+            if let Some(bytes) = arg
+                .strip_prefix(b"-s")
+                .or_else(|| arg.strip_prefix(b"--separator="))
+            {
+                Self::state_mut(interp, cmd).separator = bun_ptr::RawSlice::new(bytes);
                 idx += 1;
                 continue;
             }
@@ -75,8 +78,11 @@ impl Seq {
                 idx += 1;
                 continue;
             }
-            if arg.starts_with(b"-t") && arg.len() > 2 {
-                Self::state_mut(interp, cmd).terminator = bun_ptr::RawSlice::new(&arg[2..]);
+            if let Some(bytes) = arg
+                .strip_prefix(b"-t")
+                .or_else(|| arg.strip_prefix(b"--terminator="))
+            {
+                Self::state_mut(interp, cmd).terminator = bun_ptr::RawSlice::new(bytes);
                 idx += 1;
                 continue;
             }
diff --git a/test/js/bun/shell/commands/seq.test.ts b/test/js/bun/shell/commands/seq.test.ts
index 5ff6b24aefbc..ec8dbdb9dc9d 100644
--- a/test/js/bun/shell/commands/seq.test.ts
+++ b/test/js/bun/shell/commands/seq.test.ts
@@ -66,6 +66,30 @@ describe("seq", async () => {
     .stderr("")
     .runAsTest("--separator works");
 
+  TestBuilder.command`seq --separator=, 0 5`
+    .exitCode(0)
+    .stdout("0,1,2,3,4,5,")
+    .stderr("")
+    .runAsTest("--separator=value works");
+
+  TestBuilder.command`seq --separator= 0 5`
+    .exitCode(0)
+    .stdout("012345")
+    .stderr("")
+    .runAsTest("--separator= sets an empty separator");
+
+  TestBuilder.command`seq --separator=a=b 0 2`
+    .exitCode(0)
+    .stdout("0a=b1a=b2a=b")
+    .stderr("")
+    .runAsTest("--separator=value splits at the first = only");
+
+  TestBuilder.command`seq --separator, 0 5`
+    .exitCode(1)
+    .stdout("")
+    .stderr("seq: invalid argument\n")
+    .runAsTest("--separator needs = before an attached value");
+
   TestBuilder.command`seq -t, 0 5`.exitCode(0).stdout("0\n1\n2\n3\n4\n5\n,").stderr("").runAsTest("-t works inline");
 
   TestBuilder.command`seq -t , 0 5`.exitCode(0).stdout("0\n1\n2\n3\n4\n5\n,").stderr("").runAsTest("-t works separate");
@@ -76,12 +100,36 @@ describe("seq", async () => {
     .stderr("")
     .runAsTest("--terminator works");
 
+  TestBuilder.command`seq --terminator=, 0 5`
+    .exitCode(0)
+    .stdout("0\n1\n2\n3\n4\n5\n,")
+    .stderr("")
+    .runAsTest("--terminator=value works");
+
+  TestBuilder.command`seq --terminator= 0 2`
+    .exitCode(0)
+    .stdout("0\n1\n2\n")
+    .stderr("")
+    .runAsTest("--terminator= sets an empty terminator");
+
+  TestBuilder.command`seq --terminator, 0 5`
+    .exitCode(1)
+    .stdout("")
+    .stderr("seq: invalid argument\n")
+    .runAsTest("--terminator needs = before an attached value");
+
   TestBuilder.command`seq -s. -t, 0 5`
     .exitCode(0)
     .stdout("0.1.2.3.4.5.,")
     .stderr("")
     .runAsTest("-s and -t work together");
 
+  TestBuilder.command`seq --separator=. --terminator=, 0 5`
+    .exitCode(0)
+    .stdout("0.1.2.3.4.5.,")
+    .stderr("")
+    .runAsTest("--separator=value and --terminator=value work together");
+
   TestBuilder.command`seq 0`.exitCode(0).stdout("1\n0\n").stderr("").runAsTest("seq 0");
 
   TestBuilder.command`seq 1`.exitCode(0).stdout("1\n").stderr("").runAsTest("seq 1");