From 948def2e16ae3375c6837b5197e5ca42452d66f1 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 31 Oct 2025 18:18:57 +0000
Subject: [PATCH 1/3] Initial plan


From 9f74d75db5eb88207d84f7954cb7012bb73683fa Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 31 Oct 2025 18:36:09 +0000
Subject: [PATCH 2/3] Fix nil pointer dereference in range formatting

- Added nil check before calling getStartLineAndCharacterForNode in indent.go
- Added comprehensive test cases to verify the fix
- All tests pass successfully

Co-authored-by: DanielRosenwasser <972891+DanielRosenwasser@users.noreply.github.com>
---
 internal/format/indent.go  |  5 ++-
 internal/ls/format_test.go | 64 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 1 deletion(-)

diff --git a/internal/format/indent.go b/internal/format/indent.go
index 2565666d2f..af508586b5 100644
--- a/internal/format/indent.go
+++ b/internal/format/indent.go
@@ -66,7 +66,10 @@ func getIndentationForNodeWorker(
 			// }, {                  itself contributes nothing.
 			//   prop: 1        L3 - The indentation of the second object literal is best understood by
 			// })                    looking at the relationship between the list and *first* list item.
-			listLine, _ := getStartLineAndCharacterForNode(firstListChild, sourceFile)
+			var listLine int
+			if firstListChild != nil {
+				listLine, _ = getStartLineAndCharacterForNode(firstListChild, sourceFile)
+			}
 			listIndentsChild := firstListChild != nil && listLine > containingListOrParentStartLine
 			actualIndentation := getActualIndentationForListItem(current, sourceFile, options, listIndentsChild)
 			if actualIndentation != -1 {
diff --git a/internal/ls/format_test.go b/internal/ls/format_test.go
index b1f21d8fff..ae9403e0e0 100644
--- a/internal/ls/format_test.go
+++ b/internal/ls/format_test.go
@@ -8,6 +8,7 @@ import (
 	"github.com/microsoft/typescript-go/internal/core"
 	"github.com/microsoft/typescript-go/internal/format"
 	"github.com/microsoft/typescript-go/internal/parser"
+	"gotest.tools/v3/assert"
 )
 
 // Test for issue: Panic Handling textDocument/onTypeFormatting
@@ -70,3 +71,66 @@ func TestGetFormattingEditsAfterKeystroke_SimpleStatement(t *testing.T) {
 	// Should return nil or empty edits, not panic
 	_ = edits
 }
+
+// Test for issue: Crash in range formatting when requested on a line that is different from the containing function
+// This reproduces the panic when formatting a range inside a function body
+func TestGetFormattingEditsForRange_FunctionBody(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name     string
+		text     string
+		startPos int
+		endPos   int
+	}{
+		{
+			name:     "return statement in function",
+			text:     "function foo() {\n    return (1  + 2);\n}",
+			startPos: 21, // Start of "return"
+			endPos:   38, // End of ");"
+		},
+		{
+			name:     "function with newline after keyword",
+			text:     "function\nf() {\n}",
+			startPos: 9,  // After "function\n"
+			endPos:   13, // Inside or after function
+		},
+		{
+			name:     "empty function body",
+			text:     "function f() {\n  \n}",
+			startPos: 15, // Inside body
+			endPos:   17, // Inside body
+		},
+		{
+			name:     "after function closing brace",
+			text:     "function f() {\n}",
+			startPos: 15, // After closing brace
+			endPos:   15,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			sourceFile := parser.ParseSourceFile(ast.SourceFileParseOptions{
+				FileName: "/test.ts",
+				Path:     "/test.ts",
+			}, tc.text, core.ScriptKindTS)
+
+			langService := &LanguageService{}
+			ctx := context.Background()
+			options := format.GetDefaultFormatCodeSettings("\n")
+
+			// This should not panic
+			edits := langService.getFormattingEditsForRange(
+				ctx,
+				sourceFile,
+				options,
+				core.NewTextRange(tc.startPos, tc.endPos),
+			)
+
+			// Should not panic and should return some edits or empty array
+			assert.Assert(t, edits != nil || true) // Just ensuring no panic
+		})
+	}
+}

From 76969b2623a305a42b1d9a23ec58949689bbef3a Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Fri, 31 Oct 2025 18:49:26 +0000
Subject: [PATCH 3/3] Refactor nil check logic per code review feedback

Simplified the listIndentsChild computation by moving it inside the nil check,
avoiding redundant nil check and limiting listLine scope.

Co-authored-by: jakebailey <5341706+jakebailey@users.noreply.github.com>
---
 internal/format/indent.go | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/internal/format/indent.go b/internal/format/indent.go
index af508586b5..170873c2a4 100644
--- a/internal/format/indent.go
+++ b/internal/format/indent.go
@@ -66,11 +66,11 @@ func getIndentationForNodeWorker(
 			// }, {                  itself contributes nothing.
 			//   prop: 1        L3 - The indentation of the second object literal is best understood by
 			// })                    looking at the relationship between the list and *first* list item.
-			var listLine int
+			var listIndentsChild bool
 			if firstListChild != nil {
-				listLine, _ = getStartLineAndCharacterForNode(firstListChild, sourceFile)
+				listLine, _ := getStartLineAndCharacterForNode(firstListChild, sourceFile)
+				listIndentsChild = listLine > containingListOrParentStartLine
 			}
-			listIndentsChild := firstListChild != nil && listLine > containingListOrParentStartLine
 			actualIndentation := getActualIndentationForListItem(current, sourceFile, options, listIndentsChild)
 			if actualIndentation != -1 {
 				return actualIndentation + indentationDelta