From 4d45646bd94c790d9da7a3f09580fa328cd86024 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 8 Nov 2025 03:38:42 +0000
Subject: [PATCH 1/3] Initial plan


From 087446ed8db252c0c30c7f1070b7344b8055304a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 8 Nov 2025 03:52:30 +0000
Subject: [PATCH 2/3] Fix crash in ElementList for TupleType and add test

Co-authored-by: jakebailey <5341706+jakebailey@users.noreply.github.com>
---
 internal/ast/ast.go                           |  2 ++
 .../gen/inlayHintsTupleTypeCrash_test.go      | 22 ++++++++++++++++
 .../inlayHintsTupleTypeCrash.baseline         | 25 +++++++++++++++++++
 .../inlayHintsTupleTypeCrash.baseline.diff    | 24 ++++++++++++++++++
 4 files changed, 73 insertions(+)
 create mode 100644 internal/fourslash/tests/gen/inlayHintsTupleTypeCrash_test.go
 create mode 100644 testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline
 create mode 100644 testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline.diff

diff --git a/internal/ast/ast.go b/internal/ast/ast.go
index d2961d59c0..f0afbb925c 100644
--- a/internal/ast/ast.go
+++ b/internal/ast/ast.go
@@ -1068,6 +1068,8 @@ func (n *Node) ElementList() *NodeList {
 		return n.AsNamedExports().Elements
 	case KindObjectBindingPattern, KindArrayBindingPattern:
 		return n.AsBindingPattern().Elements
+	case KindTupleType:
+		return n.AsTupleTypeNode().Elements
 	}
 
 	panic("Unhandled case in Node.ElementList: " + n.Kind.String())
diff --git a/internal/fourslash/tests/gen/inlayHintsTupleTypeCrash_test.go b/internal/fourslash/tests/gen/inlayHintsTupleTypeCrash_test.go
new file mode 100644
index 0000000000..5df5b06667
--- /dev/null
+++ b/internal/fourslash/tests/gen/inlayHintsTupleTypeCrash_test.go
@@ -0,0 +1,22 @@
+package fourslash_test
+
+import (
+	"testing"
+
+	"github.com/microsoft/typescript-go/internal/fourslash"
+	"github.com/microsoft/typescript-go/internal/ls/lsutil"
+	"github.com/microsoft/typescript-go/internal/testutil"
+)
+
+func TestInlayHintsTupleTypeCrash(t *testing.T) {
+	t.Parallel()
+
+	defer testutil.RecoverAndFail(t, "Panic on fourslash test")
+	const content = `function iterateTuples(tuples: [string][]): void {
+  tuples.forEach((l) => {})
+}`
+	f := fourslash.NewFourslash(t, nil /*capabilities*/, content)
+	f.VerifyBaselineInlayHints(t, nil /*span*/, &lsutil.UserPreferences{
+		IncludeInlayFunctionParameterTypeHints: true,
+	})
+}
diff --git a/testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline b/testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline
new file mode 100644
index 0000000000..c4db2d46ea
--- /dev/null
+++ b/testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline
@@ -0,0 +1,25 @@
+// === Inlay Hints ===
+  tuples.forEach((l) => {})
+                   ^
+{
+  "position": {
+    "line": 1,
+    "character": 19
+  },
+  "label": [
+    {
+      "value": ": "
+    },
+    {
+      "value": "["
+    },
+    {
+      "value": "string"
+    },
+    {
+      "value": "]"
+    }
+  ],
+  "kind": 1,
+  "paddingLeft": true
+}
\ No newline at end of file
diff --git a/testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline.diff b/testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline.diff
new file mode 100644
index 0000000000..4b68d3baf3
--- /dev/null
+++ b/testdata/baselines/reference/submodule/fourslash/inlayHints/inlayHintsTupleTypeCrash.baseline.diff
@@ -0,0 +1,24 @@
+--- old.inlayHintsTupleTypeCrash.baseline
++++ new.inlayHintsTupleTypeCrash.baseline
+@@= skipped --1, +0 lines =@@
++// === Inlay Hints ===
++  tuples.forEach((l) => {})
++                   ^
++{
++  "label": [
++    {
++      "value": ": "
++    },
++    {
++      "value": "["
++    },
++    {
++      "value": "string"
++    },
++    {
++      "value": "]"
++    }
++  ],
++  "kind": 1,
++  "paddingLeft": true
++}
\ No newline at end of file

From 5dd6ebe2ea019934d509c24b932bf028b2f07cd7 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sat, 8 Nov 2025 04:10:00 +0000
Subject: [PATCH 3/3] Move test from gen to tests directory

Co-authored-by: jakebailey <5341706+jakebailey@users.noreply.github.com>
---
 .../fourslash/tests/{gen => }/inlayHintsTupleTypeCrash_test.go    | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename internal/fourslash/tests/{gen => }/inlayHintsTupleTypeCrash_test.go (100%)

diff --git a/internal/fourslash/tests/gen/inlayHintsTupleTypeCrash_test.go b/internal/fourslash/tests/inlayHintsTupleTypeCrash_test.go
similarity index 100%
rename from internal/fourslash/tests/gen/inlayHintsTupleTypeCrash_test.go
rename to internal/fourslash/tests/inlayHintsTupleTypeCrash_test.go