Fix panic in inlay hints for tuple types (#2040)

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: jakebailey <[email protected]>

Author: Copilot

internal/fourslash/tests/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,
+	})
+}

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
+}

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
++}