From 9e6ba35ff7ea46612c4e0b397be662ce9d4e19f1 Mon Sep 17 00:00:00 2001
From: pfg <pfg@pfg.pw>
Date: Wed, 1 Oct 2025 12:09:26 -0700
Subject: [PATCH] Allow multiple inline snapshots in one call if they are the
 same (#23117)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Multiple inline snapshots from one call should be avoided because they
will cause problems if one changes but not the other, but this allows
them if they both have the same value.

### What does this PR do?

bad:

```ts
function oops(a) {
  expect(a).toMatchInlineSnapshot();
}
test("whoops", () => {
  oops(1);
  oops(2);
});
```

```
2 |   expect(a).toMatchInlineSnapshot();
                                      ^
error: Failed to update inline snapshot: Multiple inline snapshots on the same line must all have the same value:
Expected: 1
Received: 2
    at /Users/pfg/Dev/Node/bun/repro.ts:2:35
```

acceptable:

```ts
function ok(a) {
  expect(a).toMatchInlineSnapshot(`1`);
}
test("whokay", () => {
  ok(1);
  ok(1);
});
```

```
✓ whokay

 1 pass
 0 fail
 snapshots: +1 added
 2 expect() calls
```

### How did you verify your code works?

TODO: add tests

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>
---
 src/bun.js/test/snapshot.zig                          | 11 ++++++++++-
 .../test/snapshot-tests/snapshots/snapshot.test.ts    |  4 +++-
 2 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/bun.js/test/snapshot.zig b/src/bun.js/test/snapshot.zig
index 398175a2eb..7562cad792 100644
--- a/src/bun.js/test/snapshot.zig
+++ b/src/bun.js/test/snapshot.zig
@@ -262,9 +262,17 @@ pub const Snapshots = struct {
             var last_byte: usize = 0;
             var last_line: c_ulong = 1;
             var last_col: c_ulong = 1;
+            var last_value: []const u8 = "";
             for (ils_info.items) |ils| {
                 if (ils.line == last_line and ils.col == last_col) {
-                    try log.addErrorFmt(source, .{ .start = @intCast(uncommitted_segment_end) }, arena, "Failed to update inline snapshot: Multiple inline snapshots for the same call are not supported", .{});
+                    if (!bun.strings.eql(ils.value, last_value)) {
+                        const DiffFormatter = @import("./diff_format.zig").DiffFormatter;
+                        try log.addErrorFmt(source, .{ .start = @intCast(uncommitted_segment_end) }, arena, "Failed to update inline snapshot: Multiple inline snapshots on the same line must all have the same value:\n{}", .{DiffFormatter{
+                            .received_string = ils.value,
+                            .expected_string = last_value,
+                            .globalThis = vm.global,
+                        }});
+                    }
                     continue;
                 }
 
@@ -279,6 +287,7 @@ pub const Snapshots = struct {
                 last_byte += byte_offset_add;
                 last_line = ils.line;
                 last_col = ils.col;
+                last_value = ils.value;
 
                 var next_start = last_byte;
                 inline_snapshot_dbg("-> Found byte {}", .{next_start});
diff --git a/test/js/bun/test/snapshot-tests/snapshots/snapshot.test.ts b/test/js/bun/test/snapshot-tests/snapshots/snapshot.test.ts
index c74a2eaaf3..db94caf377 100644
--- a/test/js/bun/test/snapshot-tests/snapshots/snapshot.test.ts
+++ b/test/js/bun/test/snapshot-tests/snapshots/snapshot.test.ts
@@ -631,7 +631,9 @@ Date)
   });
   it("should error trying to update the same line twice", () => {
     tester.testError(
-      { msg: "error: Failed to update inline snapshot: Multiple inline snapshots for the same call are not supported" },
+      {
+        msg: "error: Failed to update inline snapshot: Multiple inline snapshots on the same line must all have the same value",
+      },
       /*js*/ `
         function oops(a) {expect(a).toMatchInlineSnapshot()}
         test("whoops", () => {