From e3c1dfcc7ec3e2c8960041f04fab73484e01b335 Mon Sep 17 00:00:00 2001
From: Hamish Knight <hamish_knight@apple.com>
Date: Thu, 10 Jul 2025 18:21:50 +0100
Subject: [PATCH] [Refactoring] Handle argument count mismatches in
 `renameLabelsLenient`

Make sure we bail if we don't have enough labels in the old name when
matching against a found reference.

rdar://155549979
---
 .../SyntacticRenameRangeDetails.cpp           |  11 +-
 .../SourceKit/Refactoring/rdar155549979.swift | 105 ++++++++++++++++++
 2 files changed, 110 insertions(+), 6 deletions(-)
 create mode 100644 test/SourceKit/Refactoring/rdar155549979.swift

diff --git a/lib/Refactoring/SyntacticRenameRangeDetails.cpp b/lib/Refactoring/SyntacticRenameRangeDetails.cpp
index 6236956236c1b..efd1ed71ee27b 100644
--- a/lib/Refactoring/SyntacticRenameRangeDetails.cpp
+++ b/lib/Refactoring/SyntacticRenameRangeDetails.cpp
@@ -283,12 +283,12 @@ bool RenameRangeDetailCollector::renameLabelsLenient(
     LabelRanges = LabelRanges.take_front(*FirstTrailingLabel);
 
     for (auto LabelIndex : llvm::reverse(indices(TrailingLabels))) {
+      if (OldNames.empty())
+        return true;
+
       CharSourceRange Label = TrailingLabels[LabelIndex];
 
       if (Label.getByteLength()) {
-        if (OldNames.empty())
-          return true;
-
         while (!labelRangeMatches(Label, LabelRangeType::CompoundName,
                                   OldNames.back())) {
           if ((OldNames = OldNames.drop_back()).empty())
@@ -302,9 +302,6 @@ bool RenameRangeDetailCollector::renameLabelsLenient(
 
       // empty labelled trailing closure label
       if (LabelIndex) {
-        if (OldNames.empty())
-          return true;
-
         while (!OldNames.back().empty()) {
           if ((OldNames = OldNames.drop_back()).empty())
             return true;
@@ -330,6 +327,8 @@ bool RenameRangeDetailCollector::renameLabelsLenient(
 
       // first name pos
       if (!NameIndex) {
+        if (NameIndex >= OldNames.size())
+          return true;
         while (!OldNames[NameIndex].empty()) {
           if (++NameIndex >= OldNames.size())
             return true;
diff --git a/test/SourceKit/Refactoring/rdar155549979.swift b/test/SourceKit/Refactoring/rdar155549979.swift
new file mode 100644
index 0000000000000..c5102d4e9b2b3
--- /dev/null
+++ b/test/SourceKit/Refactoring/rdar155549979.swift
@@ -0,0 +1,105 @@
+// RUN: %empty-directory(%t)
+// RUN: split-file %s %t
+// RUN: %sourcekitd-test -req=find-rename-ranges -rename-spec %t/spec.json %t/main.swift | %FileCheck %s
+
+// REQUIRES: swift_swift_parser
+
+//--- main.swift
+func foo() {}
+
+// Make sure we don't crash on the unrelated comment refs:
+// foo()
+// foo(0)
+// foo(a: 0)
+// foo {}
+// foo {} a: {}
+
+// Nor when written in code:
+foo()
+foo(0)
+foo(a: 0)
+foo {}
+foo {} a: {}
+
+// CHECK:      source.edit.kind.active:
+// CHECK-NEXT:   1:6-1:9 source.refactoring.range.kind.basename
+// CHECK-NEXT: source.edit.kind.comment:
+// CHECK-NEXT:   4:4-4:7 source.refactoring.range.kind.basename
+// CHECK-NEXT: source.edit.kind.unknown:
+// CHECK-NEXT:   5:4-5:7 source.refactoring.range.kind.basename
+// CHECK-NEXT: source.edit.kind.unknown:
+// CHECK-NEXT:   6:4-6:7 source.refactoring.range.kind.basename
+// CHECK-NEXT: source.edit.kind.unknown:
+// CHECK-NEXT:   7:4-7:7 source.refactoring.range.kind.basename
+// CHECK-NEXT: source.edit.kind.unknown:
+// CHECK-NEXT:   8:4-8:7 source.refactoring.range.kind.basename
+// CHECK-NEXT: source.edit.kind.active:
+// CHECK-NEXT:   11:1-11:4 source.refactoring.range.kind.basename
+// CHECK-NEXT: source.edit.kind.mismatch:
+// CHECK-NEXT: source.edit.kind.mismatch:
+// CHECK-NEXT: source.edit.kind.mismatch:
+// CHECK-NEXT: source.edit.kind.mismatch:
+
+//--- spec.json
+[
+  {
+    "key.name": "foo()",
+    "key.locations": [
+      {
+        "key.line": 1,
+        "key.column": 6,
+        "key.nametype": source.syntacticrename.definition
+      },
+      {
+        "key.line": 4,
+        "key.column": 4,
+        "key.nametype": source.syntacticrename.unknown
+      },
+      {
+        "key.line": 5,
+        "key.column": 4,
+        "key.nametype": source.syntacticrename.unknown
+      },
+      {
+        "key.line": 6,
+        "key.column": 4,
+        "key.nametype": source.syntacticrename.unknown
+      },
+      {
+        "key.line": 7,
+        "key.column": 4,
+        "key.nametype": source.syntacticrename.unknown
+      },
+      {
+        "key.line": 8,
+        "key.column": 4,
+        "key.nametype": source.syntacticrename.unknown
+      },
+      {
+        "key.line": 11,
+        "key.column": 1,
+        "key.nametype": source.syntacticrename.call
+      },
+      {
+        "key.line": 12,
+        "key.column": 1,
+        "key.nametype": source.syntacticrename.call
+      },
+      {
+        "key.line": 13,
+        "key.column": 1,
+        "key.nametype": source.syntacticrename.call
+      },
+      {
+        "key.line": 14,
+        "key.column": 1,
+        "key.nametype": source.syntacticrename.call
+      },
+      {
+        "key.line": 15,
+        "key.column": 1,
+        "key.nametype": source.syntacticrename.call
+      },
+    ]
+  }
+]