fix(read_file): make indentation offset beyond EOF return empty page

src/integrations/misc/__tests__/read-file-content.spec.ts

@@ -122,14 +122,14 @@ describe("read-file-content", () => {
 
 	describe("readIndentationBlock", () => {
 		const pythonCode = `def outer():
-    x = 1
-    def inner():
-        y = 2
-        return y
-    return inner()
-
-def another():
-    pass`
+	    x = 1
+	    def inner():
+	        y = 2
+	        return y
+	    return inner()
+	
+	def another():
+	    pass`
 
 		it("should extract a function block with its contents", async () => {
 			await withTempFile("indent-function-test.py", pythonCode, async (filepath) => {
@@ -180,6 +180,16 @@ def another():
 			})
 		})
 
+		it("should return empty content when offset exceeds file length (no explicit anchorLine)", async () => {
+			await withTempFile("indent-offset-past-end-test.py", pythonCode, async (filepath) => {
+				const result = await readIndentationBlock(filepath, 100, 10)
+				expect(result.content).toBe("")
+				expect(result.lineCount).toBe(0)
+				expect(result.totalLines).toBeGreaterThan(0)
+				expect(result.metadata.totalLinesInFile).toBe(result.totalLines)
+			})
+		})
+
 		it("should handle single line result", async () => {
 			const content = "single line"
 			await withTempFile("indent-single-test.txt", content, async (filepath) => {

src/integrations/misc/read-file-content.ts

@@ -356,13 +356,9 @@ export async function readIndentationBlock(
 	limit: number = FALLBACK_LIMIT,
 	config: IndentationConfig = {},
 ): Promise<ReadFileContentResult> {
-	const {
-		anchorLine = offset,
-		maxLevels = 0,
-		includeSiblings = false,
-		includeHeader = true,
-		maxLines = limit,
-	} = config
+	const hasExplicitAnchorLine = typeof config.anchorLine === "number"
+	const anchorLine = config.anchorLine ?? offset
+	const { maxLevels = 0, includeSiblings = false, includeHeader = true, maxLines = limit } = config
 
 	if (anchorLine === 0) {
 		throw new RangeError("anchorLine must be a 1-indexed line number")
@@ -374,8 +370,53 @@ export async function readIndentationBlock(
 	// Load all lines
 	const records = await collectFileLines(filePath)
 
-	if (records.length === 0 || anchorLine > records.length) {
-		throw new RangeError("anchorLine exceeds file length")
+	// If the file is empty, match slice mode and return an empty page.
+	if (records.length === 0) {
+		return {
+			content: "",
+			lineCount: 0,
+			totalLines: 0,
+			metadata: {
+				filePath,
+				totalLinesInFile: 0,
+				linesReturned: 0,
+				startLine: anchorLine,
+				endLine: anchorLine,
+				hasMoreBefore: anchorLine > 1,
+				hasMoreAfter: false,
+				linesBeforeStart: 0,
+				linesAfterEnd: 0,
+				truncatedByLimit: false,
+				lineLengthTruncations: [],
+			},
+		}
+	}
+
+	// If offset is out-of-range and no explicit anchorLine was provided, match slice mode and return an empty page.
+	if (anchorLine > records.length) {
+		if (hasExplicitAnchorLine) {
+			throw new RangeError("anchorLine exceeds file length")
+		}
+
+		const totalLines = records.length
+		return {
+			content: "",
+			lineCount: 0,
+			totalLines,
+			metadata: {
+				filePath,
+				totalLinesInFile: totalLines,
+				linesReturned: 0,
+				startLine: anchorLine,
+				endLine: anchorLine,
+				hasMoreBefore: anchorLine > 1,
+				hasMoreAfter: false,
+				linesBeforeStart: Math.min(anchorLine - 1, totalLines),
+				linesAfterEnd: 0,
+				truncatedByLimit: false,
+				lineLengthTruncations: [],
+			},
+		}
 	}
 
 	const anchorIndex = anchorLine - 1