feat: unwrap upatch namespace to flat exports + barrel (#22709)

packages/opencode/src/patch/index.ts

@@ -1,680 +1 @@
-import z from "zod"
-import * as path from "path"
-import * as fs from "fs/promises"
-import { readFileSync } from "fs"
-import { Log } from "../util/log"
-
-export namespace Patch {
-  const log = Log.create({ service: "patch" })
-
-  // Schema definitions
-  export const PatchSchema = z.object({
-    patchText: z.string().describe("The full patch text that describes all changes to be made"),
-  })
-
-  export type PatchParams = z.infer<typeof PatchSchema>
-
-  // Core types matching the Rust implementation
-  export interface ApplyPatchArgs {
-    patch: string
-    hunks: Hunk[]
-    workdir?: string
-  }
-
-  export type Hunk =
-    | { type: "add"; path: string; contents: string }
-    | { type: "delete"; path: string }
-    | { type: "update"; path: string; move_path?: string; chunks: UpdateFileChunk[] }
-
-  export interface UpdateFileChunk {
-    old_lines: string[]
-    new_lines: string[]
-    change_context?: string
-    is_end_of_file?: boolean
-  }
-
-  export interface ApplyPatchAction {
-    changes: Map<string, ApplyPatchFileChange>
-    patch: string
-    cwd: string
-  }
-
-  export type ApplyPatchFileChange =
-    | { type: "add"; content: string }
-    | { type: "delete"; content: string }
-    | { type: "update"; unified_diff: string; move_path?: string; new_content: string }
-
-  export interface AffectedPaths {
-    added: string[]
-    modified: string[]
-    deleted: string[]
-  }
-
-  export enum ApplyPatchError {
-    ParseError = "ParseError",
-    IoError = "IoError",
-    ComputeReplacements = "ComputeReplacements",
-    ImplicitInvocation = "ImplicitInvocation",
-  }
-
-  export enum MaybeApplyPatch {
-    Body = "Body",
-    ShellParseError = "ShellParseError",
-    PatchParseError = "PatchParseError",
-    NotApplyPatch = "NotApplyPatch",
-  }
-
-  export enum MaybeApplyPatchVerified {
-    Body = "Body",
-    ShellParseError = "ShellParseError",
-    CorrectnessError = "CorrectnessError",
-    NotApplyPatch = "NotApplyPatch",
-  }
-
-  // Parser implementation
-  function parsePatchHeader(
-    lines: string[],
-    startIdx: number,
-  ): { filePath: string; movePath?: string; nextIdx: number } | null {
-    const line = lines[startIdx]
-
-    if (line.startsWith("*** Add File:")) {
-      const filePath = line.slice("*** Add File:".length).trim()
-      return filePath ? { filePath, nextIdx: startIdx + 1 } : null
-    }
-
-    if (line.startsWith("*** Delete File:")) {
-      const filePath = line.slice("*** Delete File:".length).trim()
-      return filePath ? { filePath, nextIdx: startIdx + 1 } : null
-    }
-
-    if (line.startsWith("*** Update File:")) {
-      const filePath = line.slice("*** Update File:".length).trim()
-      let movePath: string | undefined
-      let nextIdx = startIdx + 1
-
-      // Check for move directive
-      if (nextIdx < lines.length && lines[nextIdx].startsWith("*** Move to:")) {
-        movePath = lines[nextIdx].slice("*** Move to:".length).trim()
-        nextIdx++
-      }
-
-      return filePath ? { filePath, movePath, nextIdx } : null
-    }
-
-    return null
-  }
-
-  function parseUpdateFileChunks(lines: string[], startIdx: number): { chunks: UpdateFileChunk[]; nextIdx: number } {
-    const chunks: UpdateFileChunk[] = []
-    let i = startIdx
-
-    while (i < lines.length && !lines[i].startsWith("***")) {
-      if (lines[i].startsWith("@@")) {
-        // Parse context line
-        const contextLine = lines[i].substring(2).trim()
-        i++
-
-        const oldLines: string[] = []
-        const newLines: string[] = []
-        let isEndOfFile = false
-
-        // Parse change lines
-        while (i < lines.length && !lines[i].startsWith("@@") && !lines[i].startsWith("***")) {
-          const changeLine = lines[i]
-
-          if (changeLine === "*** End of File") {
-            isEndOfFile = true
-            i++
-            break
-          }
-
-          if (changeLine.startsWith(" ")) {
-            // Keep line - appears in both old and new
-            const content = changeLine.substring(1)
-            oldLines.push(content)
-            newLines.push(content)
-          } else if (changeLine.startsWith("-")) {
-            // Remove line - only in old
-            oldLines.push(changeLine.substring(1))
-          } else if (changeLine.startsWith("+")) {
-            // Add line - only in new
-            newLines.push(changeLine.substring(1))
-          }
-
-          i++
-        }
-
-        chunks.push({
-          old_lines: oldLines,
-          new_lines: newLines,
-          change_context: contextLine || undefined,
-          is_end_of_file: isEndOfFile || undefined,
-        })
-      } else {
-        i++
-      }
-    }
-
-    return { chunks, nextIdx: i }
-  }
-
-  function parseAddFileContent(lines: string[], startIdx: number): { content: string; nextIdx: number } {
-    let content = ""
-    let i = startIdx
-
-    while (i < lines.length && !lines[i].startsWith("***")) {
-      if (lines[i].startsWith("+")) {
-        content += lines[i].substring(1) + "\n"
-      }
-      i++
-    }
-
-    // Remove trailing newline
-    if (content.endsWith("\n")) {
-      content = content.slice(0, -1)
-    }
-
-    return { content, nextIdx: i }
-  }
-
-  function stripHeredoc(input: string): string {
-    // Match heredoc patterns like: cat <<'EOF'\n...\nEOF or <<EOF\n...\nEOF
-    const heredocMatch = input.match(/^(?:cat\s+)?<<['"]?(\w+)['"]?\s*\n([\s\S]*?)\n\1\s*$/)
-    if (heredocMatch) {
-      return heredocMatch[2]
-    }
-    return input
-  }
-
-  export function parsePatch(patchText: string): { hunks: Hunk[] } {
-    const cleaned = stripHeredoc(patchText.trim())
-    const lines = cleaned.split("\n")
-    const hunks: Hunk[] = []
-    let i = 0
-
-    // Look for Begin/End patch markers
-    const beginMarker = "*** Begin Patch"
-    const endMarker = "*** End Patch"
-
-    const beginIdx = lines.findIndex((line) => line.trim() === beginMarker)
-    const endIdx = lines.findIndex((line) => line.trim() === endMarker)
-
-    if (beginIdx === -1 || endIdx === -1 || beginIdx >= endIdx) {
-      throw new Error("Invalid patch format: missing Begin/End markers")
-    }
-
-    // Parse content between markers
-    i = beginIdx + 1
-
-    while (i < endIdx) {
-      const header = parsePatchHeader(lines, i)
-      if (!header) {
-        i++
-        continue
-      }
-
-      if (lines[i].startsWith("*** Add File:")) {
-        const { content, nextIdx } = parseAddFileContent(lines, header.nextIdx)
-        hunks.push({
-          type: "add",
-          path: header.filePath,
-          contents: content,
-        })
-        i = nextIdx
-      } else if (lines[i].startsWith("*** Delete File:")) {
-        hunks.push({
-          type: "delete",
-          path: header.filePath,
-        })
-        i = header.nextIdx
-      } else if (lines[i].startsWith("*** Update File:")) {
-        const { chunks, nextIdx } = parseUpdateFileChunks(lines, header.nextIdx)
-        hunks.push({
-          type: "update",
-          path: header.filePath,
-          move_path: header.movePath,
-          chunks,
-        })
-        i = nextIdx
-      } else {
-        i++
-      }
-    }
-
-    return { hunks }
-  }
-
-  // Apply patch functionality
-  export function maybeParseApplyPatch(
-    argv: string[],
-  ):
-    | { type: MaybeApplyPatch.Body; args: ApplyPatchArgs }
-    | { type: MaybeApplyPatch.PatchParseError; error: Error }
-    | { type: MaybeApplyPatch.NotApplyPatch } {
-    const APPLY_PATCH_COMMANDS = ["apply_patch", "applypatch"]
-
-    // Direct invocation: apply_patch <patch>
-    if (argv.length === 2 && APPLY_PATCH_COMMANDS.includes(argv[0])) {
-      try {
-        const { hunks } = parsePatch(argv[1])
-        return {
-          type: MaybeApplyPatch.Body,
-          args: {
-            patch: argv[1],
-            hunks,
-          },
-        }
-      } catch (error) {
-        return {
-          type: MaybeApplyPatch.PatchParseError,
-          error: error as Error,
-        }
-      }
-    }
-
-    // Bash heredoc form: bash -lc 'apply_patch <<"EOF" ...'
-    if (argv.length === 3 && argv[0] === "bash" && argv[1] === "-lc") {
-      // Simple extraction - in real implementation would need proper bash parsing
-      const script = argv[2]
-      const heredocMatch = script.match(/apply_patch\s*<<['"](\w+)['"]\s*\n([\s\S]*?)\n\1/)
-
-      if (heredocMatch) {
-        const patchContent = heredocMatch[2]
-        try {
-          const { hunks } = parsePatch(patchContent)
-          return {
-            type: MaybeApplyPatch.Body,
-            args: {
-              patch: patchContent,
-              hunks,
-            },
-          }
-        } catch (error) {
-          return {
-            type: MaybeApplyPatch.PatchParseError,
-            error: error as Error,
-          }
-        }
-      }
-    }
-
-    return { type: MaybeApplyPatch.NotApplyPatch }
-  }
-
-  // File content manipulation
-  interface ApplyPatchFileUpdate {
-    unified_diff: string
-    content: string
-  }
-
-  export function deriveNewContentsFromChunks(filePath: string, chunks: UpdateFileChunk[]): ApplyPatchFileUpdate {
-    // Read original file content
-    let originalContent: string
-    try {
-      originalContent = readFileSync(filePath, "utf-8")
-    } catch (error) {
-      throw new Error(`Failed to read file ${filePath}: ${error}`)
-    }
-
-    let originalLines = originalContent.split("\n")
-
-    // Drop trailing empty element for consistent line counting
-    if (originalLines.length > 0 && originalLines[originalLines.length - 1] === "") {
-      originalLines.pop()
-    }
-
-    const replacements = computeReplacements(originalLines, filePath, chunks)
-    let newLines = applyReplacements(originalLines, replacements)
-
-    // Ensure trailing newline
-    if (newLines.length === 0 || newLines[newLines.length - 1] !== "") {
-      newLines.push("")
-    }
-
-    const newContent = newLines.join("\n")
-
-    // Generate unified diff
-    const unifiedDiff = generateUnifiedDiff(originalContent, newContent)
-
-    return {
-      unified_diff: unifiedDiff,
-      content: newContent,
-    }
-  }
-
-  function computeReplacements(
-    originalLines: string[],
-    filePath: string,
-    chunks: UpdateFileChunk[],
-  ): Array<[number, number, string[]]> {
-    const replacements: Array<[number, number, string[]]> = []
-    let lineIndex = 0
-
-    for (const chunk of chunks) {
-      // Handle context-based seeking
-      if (chunk.change_context) {
-        const contextIdx = seekSequence(originalLines, [chunk.change_context], lineIndex)
-        if (contextIdx === -1) {
-          throw new Error(`Failed to find context '${chunk.change_context}' in ${filePath}`)
-        }
-        lineIndex = contextIdx + 1
-      }
-
-      // Handle pure addition (no old lines)
-      if (chunk.old_lines.length === 0) {
-        const insertionIdx =
-          originalLines.length > 0 && originalLines[originalLines.length - 1] === ""
-            ? originalLines.length - 1
-            : originalLines.length
-        replacements.push([insertionIdx, 0, chunk.new_lines])
-        continue
-      }
-
-      // Try to match old lines in the file
-      let pattern = chunk.old_lines
-      let newSlice = chunk.new_lines
-      let found = seekSequence(originalLines, pattern, lineIndex, chunk.is_end_of_file)
-
-      // Retry without trailing empty line if not found
-      if (found === -1 && pattern.length > 0 && pattern[pattern.length - 1] === "") {
-        pattern = pattern.slice(0, -1)
-        if (newSlice.length > 0 && newSlice[newSlice.length - 1] === "") {
-          newSlice = newSlice.slice(0, -1)
-        }
-        found = seekSequence(originalLines, pattern, lineIndex, chunk.is_end_of_file)
-      }
-
-      if (found !== -1) {
-        replacements.push([found, pattern.length, newSlice])
-        lineIndex = found + pattern.length
-      } else {
-        throw new Error(`Failed to find expected lines in ${filePath}:\n${chunk.old_lines.join("\n")}`)
-      }
-    }
-
-    // Sort replacements by index to apply in order
-    replacements.sort((a, b) => a[0] - b[0])
-
-    return replacements
-  }
-
-  function applyReplacements(lines: string[], replacements: Array<[number, number, string[]]>): string[] {
-    // Apply replacements in reverse order to avoid index shifting
-    const result = [...lines]
-
-    for (let i = replacements.length - 1; i >= 0; i--) {
-      const [startIdx, oldLen, newSegment] = replacements[i]
-
-      // Remove old lines
-      result.splice(startIdx, oldLen)
-
-      // Insert new lines
-      for (let j = 0; j < newSegment.length; j++) {
-        result.splice(startIdx + j, 0, newSegment[j])
-      }
-    }
-
-    return result
-  }
-
-  // Normalize Unicode punctuation to ASCII equivalents (like Rust's normalize_unicode)
-  function normalizeUnicode(str: string): string {
-    return str
-      .replace(/[\u2018\u2019\u201A\u201B]/g, "'") // single quotes
-      .replace(/[\u201C\u201D\u201E\u201F]/g, '"') // double quotes
-      .replace(/[\u2010\u2011\u2012\u2013\u2014\u2015]/g, "-") // dashes
-      .replace(/\u2026/g, "...") // ellipsis
-      .replace(/\u00A0/g, " ") // non-breaking space
-  }
-
-  type Comparator = (a: string, b: string) => boolean
-
-  function tryMatch(lines: string[], pattern: string[], startIndex: number, compare: Comparator, eof: boolean): number {
-    // If EOF anchor, try matching from end of file first
-    if (eof) {
-      const fromEnd = lines.length - pattern.length
-      if (fromEnd >= startIndex) {
-        let matches = true
-        for (let j = 0; j < pattern.length; j++) {
-          if (!compare(lines[fromEnd + j], pattern[j])) {
-            matches = false
-            break
-          }
-        }
-        if (matches) return fromEnd
-      }
-    }
-
-    // Forward search from startIndex
-    for (let i = startIndex; i <= lines.length - pattern.length; i++) {
-      let matches = true
-      for (let j = 0; j < pattern.length; j++) {
-        if (!compare(lines[i + j], pattern[j])) {
-          matches = false
-          break
-        }
-      }
-      if (matches) return i
-    }
-
-    return -1
-  }
-
-  function seekSequence(lines: string[], pattern: string[], startIndex: number, eof = false): number {
-    if (pattern.length === 0) return -1
-
-    // Pass 1: exact match
-    const exact = tryMatch(lines, pattern, startIndex, (a, b) => a === b, eof)
-    if (exact !== -1) return exact
-
-    // Pass 2: rstrip (trim trailing whitespace)
-    const rstrip = tryMatch(lines, pattern, startIndex, (a, b) => a.trimEnd() === b.trimEnd(), eof)
-    if (rstrip !== -1) return rstrip
-
-    // Pass 3: trim (both ends)
-    const trim = tryMatch(lines, pattern, startIndex, (a, b) => a.trim() === b.trim(), eof)
-    if (trim !== -1) return trim
-
-    // Pass 4: normalized (Unicode punctuation to ASCII)
-    const normalized = tryMatch(
-      lines,
-      pattern,
-      startIndex,
-      (a, b) => normalizeUnicode(a.trim()) === normalizeUnicode(b.trim()),
-      eof,
-    )
-    return normalized
-  }
-
-  function generateUnifiedDiff(oldContent: string, newContent: string): string {
-    const oldLines = oldContent.split("\n")
-    const newLines = newContent.split("\n")
-
-    // Simple diff generation - in a real implementation you'd use a proper diff algorithm
-    let diff = "@@ -1 +1 @@\n"
-
-    // Find changes (simplified approach)
-    const maxLen = Math.max(oldLines.length, newLines.length)
-    let hasChanges = false
-
-    for (let i = 0; i < maxLen; i++) {
-      const oldLine = oldLines[i] || ""
-      const newLine = newLines[i] || ""
-
-      if (oldLine !== newLine) {
-        if (oldLine) diff += `-${oldLine}\n`
-        if (newLine) diff += `+${newLine}\n`
-        hasChanges = true
-      } else if (oldLine) {
-        diff += ` ${oldLine}\n`
-      }
-    }
-
-    return hasChanges ? diff : ""
-  }
-
-  // Apply hunks to filesystem
-  export async function applyHunksToFiles(hunks: Hunk[]): Promise<AffectedPaths> {
-    if (hunks.length === 0) {
-      throw new Error("No files were modified.")
-    }
-
-    const added: string[] = []
-    const modified: string[] = []
-    const deleted: string[] = []
-
-    for (const hunk of hunks) {
-      switch (hunk.type) {
-        case "add":
-          // Create parent directories
-          const addDir = path.dirname(hunk.path)
-          if (addDir !== "." && addDir !== "/") {
-            await fs.mkdir(addDir, { recursive: true })
-          }
-
-          await fs.writeFile(hunk.path, hunk.contents, "utf-8")
-          added.push(hunk.path)
-          log.info(`Added file: ${hunk.path}`)
-          break
-
-        case "delete":
-          await fs.unlink(hunk.path)
-          deleted.push(hunk.path)
-          log.info(`Deleted file: ${hunk.path}`)
-          break
-
-        case "update":
-          const fileUpdate = deriveNewContentsFromChunks(hunk.path, hunk.chunks)
-
-          if (hunk.move_path) {
-            // Handle file move
-            const moveDir = path.dirname(hunk.move_path)
-            if (moveDir !== "." && moveDir !== "/") {
-              await fs.mkdir(moveDir, { recursive: true })
-            }
-
-            await fs.writeFile(hunk.move_path, fileUpdate.content, "utf-8")
-            await fs.unlink(hunk.path)
-            modified.push(hunk.move_path)
-            log.info(`Moved file: ${hunk.path} -> ${hunk.move_path}`)
-          } else {
-            // Regular update
-            await fs.writeFile(hunk.path, fileUpdate.content, "utf-8")
-            modified.push(hunk.path)
-            log.info(`Updated file: ${hunk.path}`)
-          }
-          break
-      }
-    }
-
-    return { added, modified, deleted }
-  }
-
-  // Main patch application function
-  export async function applyPatch(patchText: string): Promise<AffectedPaths> {
-    const { hunks } = parsePatch(patchText)
-    return applyHunksToFiles(hunks)
-  }
-
-  // Async version of maybeParseApplyPatchVerified
-  export async function maybeParseApplyPatchVerified(
-    argv: string[],
-    cwd: string,
-  ): Promise<
-    | { type: MaybeApplyPatchVerified.Body; action: ApplyPatchAction }
-    | { type: MaybeApplyPatchVerified.CorrectnessError; error: Error }
-    | { type: MaybeApplyPatchVerified.NotApplyPatch }
-  > {
-    // Detect implicit patch invocation (raw patch without apply_patch command)
-    if (argv.length === 1) {
-      try {
-        parsePatch(argv[0])
-        return {
-          type: MaybeApplyPatchVerified.CorrectnessError,
-          error: new Error(ApplyPatchError.ImplicitInvocation),
-        }
-      } catch {
-        // Not a patch, continue
-      }
-    }
-
-    const result = maybeParseApplyPatch(argv)
-
-    switch (result.type) {
-      case MaybeApplyPatch.Body:
-        const { args } = result
-        const effectiveCwd = args.workdir ? path.resolve(cwd, args.workdir) : cwd
-        const changes = new Map<string, ApplyPatchFileChange>()
-
-        for (const hunk of args.hunks) {
-          const resolvedPath = path.resolve(
-            effectiveCwd,
-            hunk.type === "update" && hunk.move_path ? hunk.move_path : hunk.path,
-          )
-
-          switch (hunk.type) {
-            case "add":
-              changes.set(resolvedPath, {
-                type: "add",
-                content: hunk.contents,
-              })
-              break
-
-            case "delete":
-              // For delete, we need to read the current content
-              const deletePath = path.resolve(effectiveCwd, hunk.path)
-              try {
-                const content = await fs.readFile(deletePath, "utf-8")
-                changes.set(resolvedPath, {
-                  type: "delete",
-                  content,
-                })
-              } catch {
-                return {
-                  type: MaybeApplyPatchVerified.CorrectnessError,
-                  error: new Error(`Failed to read file for deletion: ${deletePath}`),
-                }
-              }
-              break
-
-            case "update":
-              const updatePath = path.resolve(effectiveCwd, hunk.path)
-              try {
-                const fileUpdate = deriveNewContentsFromChunks(updatePath, hunk.chunks)
-                changes.set(resolvedPath, {
-                  type: "update",
-                  unified_diff: fileUpdate.unified_diff,
-                  move_path: hunk.move_path ? path.resolve(effectiveCwd, hunk.move_path) : undefined,
-                  new_content: fileUpdate.content,
-                })
-              } catch (error) {
-                return {
-                  type: MaybeApplyPatchVerified.CorrectnessError,
-                  error: error as Error,
-                }
-              }
-              break
-          }
-        }
-
-        return {
-          type: MaybeApplyPatchVerified.Body,
-          action: {
-            changes,
-            patch: args.patch,
-            cwd: effectiveCwd,
-          },
-        }
-
-      case MaybeApplyPatch.PatchParseError:
-        return {
-          type: MaybeApplyPatchVerified.CorrectnessError,
-          error: result.error,
-        }
-
-      case MaybeApplyPatch.NotApplyPatch:
-        return { type: MaybeApplyPatchVerified.NotApplyPatch }
-    }
-  }
-}
+export * as Patch from "./patch"

packages/opencode/src/patch/patch.ts

@@ -0,0 +1,678 @@
+import z from "zod"
+import * as path from "path"
+import * as fs from "fs/promises"
+import { readFileSync } from "fs"
+import { Log } from "../util/log"
+
+const log = Log.create({ service: "patch" })
+
+// Schema definitions
+export const PatchSchema = z.object({
+  patchText: z.string().describe("The full patch text that describes all changes to be made"),
+})
+
+export type PatchParams = z.infer<typeof PatchSchema>
+
+// Core types matching the Rust implementation
+export interface ApplyPatchArgs {
+  patch: string
+  hunks: Hunk[]
+  workdir?: string
+}
+
+export type Hunk =
+  | { type: "add"; path: string; contents: string }
+  | { type: "delete"; path: string }
+  | { type: "update"; path: string; move_path?: string; chunks: UpdateFileChunk[] }
+
+export interface UpdateFileChunk {
+  old_lines: string[]
+  new_lines: string[]
+  change_context?: string
+  is_end_of_file?: boolean
+}
+
+export interface ApplyPatchAction {
+  changes: Map<string, ApplyPatchFileChange>
+  patch: string
+  cwd: string
+}
+
+export type ApplyPatchFileChange =
+  | { type: "add"; content: string }
+  | { type: "delete"; content: string }
+  | { type: "update"; unified_diff: string; move_path?: string; new_content: string }
+
+export interface AffectedPaths {
+  added: string[]
+  modified: string[]
+  deleted: string[]
+}
+
+export enum ApplyPatchError {
+  ParseError = "ParseError",
+  IoError = "IoError",
+  ComputeReplacements = "ComputeReplacements",
+  ImplicitInvocation = "ImplicitInvocation",
+}
+
+export enum MaybeApplyPatch {
+  Body = "Body",
+  ShellParseError = "ShellParseError",
+  PatchParseError = "PatchParseError",
+  NotApplyPatch = "NotApplyPatch",
+}
+
+export enum MaybeApplyPatchVerified {
+  Body = "Body",
+  ShellParseError = "ShellParseError",
+  CorrectnessError = "CorrectnessError",
+  NotApplyPatch = "NotApplyPatch",
+}
+
+// Parser implementation
+function parsePatchHeader(
+  lines: string[],
+  startIdx: number,
+): { filePath: string; movePath?: string; nextIdx: number } | null {
+  const line = lines[startIdx]
+
+  if (line.startsWith("*** Add File:")) {
+    const filePath = line.slice("*** Add File:".length).trim()
+    return filePath ? { filePath, nextIdx: startIdx + 1 } : null
+  }
+
+  if (line.startsWith("*** Delete File:")) {
+    const filePath = line.slice("*** Delete File:".length).trim()
+    return filePath ? { filePath, nextIdx: startIdx + 1 } : null
+  }
+
+  if (line.startsWith("*** Update File:")) {
+    const filePath = line.slice("*** Update File:".length).trim()
+    let movePath: string | undefined
+    let nextIdx = startIdx + 1
+
+    // Check for move directive
+    if (nextIdx < lines.length && lines[nextIdx].startsWith("*** Move to:")) {
+      movePath = lines[nextIdx].slice("*** Move to:".length).trim()
+      nextIdx++
+    }
+
+    return filePath ? { filePath, movePath, nextIdx } : null
+  }
+
+  return null
+}
+
+function parseUpdateFileChunks(lines: string[], startIdx: number): { chunks: UpdateFileChunk[]; nextIdx: number } {
+  const chunks: UpdateFileChunk[] = []
+  let i = startIdx
+
+  while (i < lines.length && !lines[i].startsWith("***")) {
+    if (lines[i].startsWith("@@")) {
+      // Parse context line
+      const contextLine = lines[i].substring(2).trim()
+      i++
+
+      const oldLines: string[] = []
+      const newLines: string[] = []
+      let isEndOfFile = false
+
+      // Parse change lines
+      while (i < lines.length && !lines[i].startsWith("@@") && !lines[i].startsWith("***")) {
+        const changeLine = lines[i]
+
+        if (changeLine === "*** End of File") {
+          isEndOfFile = true
+          i++
+          break
+        }
+
+        if (changeLine.startsWith(" ")) {
+          // Keep line - appears in both old and new
+          const content = changeLine.substring(1)
+          oldLines.push(content)
+          newLines.push(content)
+        } else if (changeLine.startsWith("-")) {
+          // Remove line - only in old
+          oldLines.push(changeLine.substring(1))
+        } else if (changeLine.startsWith("+")) {
+          // Add line - only in new
+          newLines.push(changeLine.substring(1))
+        }
+
+        i++
+      }
+
+      chunks.push({
+        old_lines: oldLines,
+        new_lines: newLines,
+        change_context: contextLine || undefined,
+        is_end_of_file: isEndOfFile || undefined,
+      })
+    } else {
+      i++
+    }
+  }
+
+  return { chunks, nextIdx: i }
+}
+
+function parseAddFileContent(lines: string[], startIdx: number): { content: string; nextIdx: number } {
+  let content = ""
+  let i = startIdx
+
+  while (i < lines.length && !lines[i].startsWith("***")) {
+    if (lines[i].startsWith("+")) {
+      content += lines[i].substring(1) + "\n"
+    }
+    i++
+  }
+
+  // Remove trailing newline
+  if (content.endsWith("\n")) {
+    content = content.slice(0, -1)
+  }
+
+  return { content, nextIdx: i }
+}
+
+function stripHeredoc(input: string): string {
+  // Match heredoc patterns like: cat <<'EOF'\n...\nEOF or <<EOF\n...\nEOF
+  const heredocMatch = input.match(/^(?:cat\s+)?<<['"]?(\w+)['"]?\s*\n([\s\S]*?)\n\1\s*$/)
+  if (heredocMatch) {
+    return heredocMatch[2]
+  }
+  return input
+}
+
+export function parsePatch(patchText: string): { hunks: Hunk[] } {
+  const cleaned = stripHeredoc(patchText.trim())
+  const lines = cleaned.split("\n")
+  const hunks: Hunk[] = []
+  let i = 0
+
+  // Look for Begin/End patch markers
+  const beginMarker = "*** Begin Patch"
+  const endMarker = "*** End Patch"
+
+  const beginIdx = lines.findIndex((line) => line.trim() === beginMarker)
+  const endIdx = lines.findIndex((line) => line.trim() === endMarker)
+
+  if (beginIdx === -1 || endIdx === -1 || beginIdx >= endIdx) {
+    throw new Error("Invalid patch format: missing Begin/End markers")
+  }
+
+  // Parse content between markers
+  i = beginIdx + 1
+
+  while (i < endIdx) {
+    const header = parsePatchHeader(lines, i)
+    if (!header) {
+      i++
+      continue
+    }
+
+    if (lines[i].startsWith("*** Add File:")) {
+      const { content, nextIdx } = parseAddFileContent(lines, header.nextIdx)
+      hunks.push({
+        type: "add",
+        path: header.filePath,
+        contents: content,
+      })
+      i = nextIdx
+    } else if (lines[i].startsWith("*** Delete File:")) {
+      hunks.push({
+        type: "delete",
+        path: header.filePath,
+      })
+      i = header.nextIdx
+    } else if (lines[i].startsWith("*** Update File:")) {
+      const { chunks, nextIdx } = parseUpdateFileChunks(lines, header.nextIdx)
+      hunks.push({
+        type: "update",
+        path: header.filePath,
+        move_path: header.movePath,
+        chunks,
+      })
+      i = nextIdx
+    } else {
+      i++
+    }
+  }
+
+  return { hunks }
+}
+
+// Apply patch functionality
+export function maybeParseApplyPatch(
+  argv: string[],
+):
+  | { type: MaybeApplyPatch.Body; args: ApplyPatchArgs }
+  | { type: MaybeApplyPatch.PatchParseError; error: Error }
+  | { type: MaybeApplyPatch.NotApplyPatch } {
+  const APPLY_PATCH_COMMANDS = ["apply_patch", "applypatch"]
+
+  // Direct invocation: apply_patch <patch>
+  if (argv.length === 2 && APPLY_PATCH_COMMANDS.includes(argv[0])) {
+    try {
+      const { hunks } = parsePatch(argv[1])
+      return {
+        type: MaybeApplyPatch.Body,
+        args: {
+          patch: argv[1],
+          hunks,
+        },
+      }
+    } catch (error) {
+      return {
+        type: MaybeApplyPatch.PatchParseError,
+        error: error as Error,
+      }
+    }
+  }
+
+  // Bash heredoc form: bash -lc 'apply_patch <<"EOF" ...'
+  if (argv.length === 3 && argv[0] === "bash" && argv[1] === "-lc") {
+    // Simple extraction - in real implementation would need proper bash parsing
+    const script = argv[2]
+    const heredocMatch = script.match(/apply_patch\s*<<['"](\w+)['"]\s*\n([\s\S]*?)\n\1/)
+
+    if (heredocMatch) {
+      const patchContent = heredocMatch[2]
+      try {
+        const { hunks } = parsePatch(patchContent)
+        return {
+          type: MaybeApplyPatch.Body,
+          args: {
+            patch: patchContent,
+            hunks,
+          },
+        }
+      } catch (error) {
+        return {
+          type: MaybeApplyPatch.PatchParseError,
+          error: error as Error,
+        }
+      }
+    }
+  }
+
+  return { type: MaybeApplyPatch.NotApplyPatch }
+}
+
+// File content manipulation
+interface ApplyPatchFileUpdate {
+  unified_diff: string
+  content: string
+}
+
+export function deriveNewContentsFromChunks(filePath: string, chunks: UpdateFileChunk[]): ApplyPatchFileUpdate {
+  // Read original file content
+  let originalContent: string
+  try {
+    originalContent = readFileSync(filePath, "utf-8")
+  } catch (error) {
+    throw new Error(`Failed to read file ${filePath}: ${error}`)
+  }
+
+  let originalLines = originalContent.split("\n")
+
+  // Drop trailing empty element for consistent line counting
+  if (originalLines.length > 0 && originalLines[originalLines.length - 1] === "") {
+    originalLines.pop()
+  }
+
+  const replacements = computeReplacements(originalLines, filePath, chunks)
+  let newLines = applyReplacements(originalLines, replacements)
+
+  // Ensure trailing newline
+  if (newLines.length === 0 || newLines[newLines.length - 1] !== "") {
+    newLines.push("")
+  }
+
+  const newContent = newLines.join("\n")
+
+  // Generate unified diff
+  const unifiedDiff = generateUnifiedDiff(originalContent, newContent)
+
+  return {
+    unified_diff: unifiedDiff,
+    content: newContent,
+  }
+}
+
+function computeReplacements(
+  originalLines: string[],
+  filePath: string,
+  chunks: UpdateFileChunk[],
+): Array<[number, number, string[]]> {
+  const replacements: Array<[number, number, string[]]> = []
+  let lineIndex = 0
+
+  for (const chunk of chunks) {
+    // Handle context-based seeking
+    if (chunk.change_context) {
+      const contextIdx = seekSequence(originalLines, [chunk.change_context], lineIndex)
+      if (contextIdx === -1) {
+        throw new Error(`Failed to find context '${chunk.change_context}' in ${filePath}`)
+      }
+      lineIndex = contextIdx + 1
+    }
+
+    // Handle pure addition (no old lines)
+    if (chunk.old_lines.length === 0) {
+      const insertionIdx =
+        originalLines.length > 0 && originalLines[originalLines.length - 1] === ""
+          ? originalLines.length - 1
+          : originalLines.length
+      replacements.push([insertionIdx, 0, chunk.new_lines])
+      continue
+    }
+
+    // Try to match old lines in the file
+    let pattern = chunk.old_lines
+    let newSlice = chunk.new_lines
+    let found = seekSequence(originalLines, pattern, lineIndex, chunk.is_end_of_file)
+
+    // Retry without trailing empty line if not found
+    if (found === -1 && pattern.length > 0 && pattern[pattern.length - 1] === "") {
+      pattern = pattern.slice(0, -1)
+      if (newSlice.length > 0 && newSlice[newSlice.length - 1] === "") {
+        newSlice = newSlice.slice(0, -1)
+      }
+      found = seekSequence(originalLines, pattern, lineIndex, chunk.is_end_of_file)
+    }
+
+    if (found !== -1) {
+      replacements.push([found, pattern.length, newSlice])
+      lineIndex = found + pattern.length
+    } else {
+      throw new Error(`Failed to find expected lines in ${filePath}:\n${chunk.old_lines.join("\n")}`)
+    }
+  }
+
+  // Sort replacements by index to apply in order
+  replacements.sort((a, b) => a[0] - b[0])
+
+  return replacements
+}
+
+function applyReplacements(lines: string[], replacements: Array<[number, number, string[]]>): string[] {
+  // Apply replacements in reverse order to avoid index shifting
+  const result = [...lines]
+
+  for (let i = replacements.length - 1; i >= 0; i--) {
+    const [startIdx, oldLen, newSegment] = replacements[i]
+
+    // Remove old lines
+    result.splice(startIdx, oldLen)
+
+    // Insert new lines
+    for (let j = 0; j < newSegment.length; j++) {
+      result.splice(startIdx + j, 0, newSegment[j])
+    }
+  }
+
+  return result
+}
+
+// Normalize Unicode punctuation to ASCII equivalents (like Rust's normalize_unicode)
+function normalizeUnicode(str: string): string {
+  return str
+    .replace(/[\u2018\u2019\u201A\u201B]/g, "'") // single quotes
+    .replace(/[\u201C\u201D\u201E\u201F]/g, '"') // double quotes
+    .replace(/[\u2010\u2011\u2012\u2013\u2014\u2015]/g, "-") // dashes
+    .replace(/\u2026/g, "...") // ellipsis
+    .replace(/\u00A0/g, " ") // non-breaking space
+}
+
+type Comparator = (a: string, b: string) => boolean
+
+function tryMatch(lines: string[], pattern: string[], startIndex: number, compare: Comparator, eof: boolean): number {
+  // If EOF anchor, try matching from end of file first
+  if (eof) {
+    const fromEnd = lines.length - pattern.length
+    if (fromEnd >= startIndex) {
+      let matches = true
+      for (let j = 0; j < pattern.length; j++) {
+        if (!compare(lines[fromEnd + j], pattern[j])) {
+          matches = false
+          break
+        }
+      }
+      if (matches) return fromEnd
+    }
+  }
+
+  // Forward search from startIndex
+  for (let i = startIndex; i <= lines.length - pattern.length; i++) {
+    let matches = true
+    for (let j = 0; j < pattern.length; j++) {
+      if (!compare(lines[i + j], pattern[j])) {
+        matches = false
+        break
+      }
+    }
+    if (matches) return i
+  }
+
+  return -1
+}
+
+function seekSequence(lines: string[], pattern: string[], startIndex: number, eof = false): number {
+  if (pattern.length === 0) return -1
+
+  // Pass 1: exact match
+  const exact = tryMatch(lines, pattern, startIndex, (a, b) => a === b, eof)
+  if (exact !== -1) return exact
+
+  // Pass 2: rstrip (trim trailing whitespace)
+  const rstrip = tryMatch(lines, pattern, startIndex, (a, b) => a.trimEnd() === b.trimEnd(), eof)
+  if (rstrip !== -1) return rstrip
+
+  // Pass 3: trim (both ends)
+  const trim = tryMatch(lines, pattern, startIndex, (a, b) => a.trim() === b.trim(), eof)
+  if (trim !== -1) return trim
+
+  // Pass 4: normalized (Unicode punctuation to ASCII)
+  const normalized = tryMatch(
+    lines,
+    pattern,
+    startIndex,
+    (a, b) => normalizeUnicode(a.trim()) === normalizeUnicode(b.trim()),
+    eof,
+  )
+  return normalized
+}
+
+function generateUnifiedDiff(oldContent: string, newContent: string): string {
+  const oldLines = oldContent.split("\n")
+  const newLines = newContent.split("\n")
+
+  // Simple diff generation - in a real implementation you'd use a proper diff algorithm
+  let diff = "@@ -1 +1 @@\n"
+
+  // Find changes (simplified approach)
+  const maxLen = Math.max(oldLines.length, newLines.length)
+  let hasChanges = false
+
+  for (let i = 0; i < maxLen; i++) {
+    const oldLine = oldLines[i] || ""
+    const newLine = newLines[i] || ""
+
+    if (oldLine !== newLine) {
+      if (oldLine) diff += `-${oldLine}\n`
+      if (newLine) diff += `+${newLine}\n`
+      hasChanges = true
+    } else if (oldLine) {
+      diff += ` ${oldLine}\n`
+    }
+  }
+
+  return hasChanges ? diff : ""
+}
+
+// Apply hunks to filesystem
+export async function applyHunksToFiles(hunks: Hunk[]): Promise<AffectedPaths> {
+  if (hunks.length === 0) {
+    throw new Error("No files were modified.")
+  }
+
+  const added: string[] = []
+  const modified: string[] = []
+  const deleted: string[] = []
+
+  for (const hunk of hunks) {
+    switch (hunk.type) {
+      case "add":
+        // Create parent directories
+        const addDir = path.dirname(hunk.path)
+        if (addDir !== "." && addDir !== "/") {
+          await fs.mkdir(addDir, { recursive: true })
+        }
+
+        await fs.writeFile(hunk.path, hunk.contents, "utf-8")
+        added.push(hunk.path)
+        log.info(`Added file: ${hunk.path}`)
+        break
+
+      case "delete":
+        await fs.unlink(hunk.path)
+        deleted.push(hunk.path)
+        log.info(`Deleted file: ${hunk.path}`)
+        break
+
+      case "update":
+        const fileUpdate = deriveNewContentsFromChunks(hunk.path, hunk.chunks)
+
+        if (hunk.move_path) {
+          // Handle file move
+          const moveDir = path.dirname(hunk.move_path)
+          if (moveDir !== "." && moveDir !== "/") {
+            await fs.mkdir(moveDir, { recursive: true })
+          }
+
+          await fs.writeFile(hunk.move_path, fileUpdate.content, "utf-8")
+          await fs.unlink(hunk.path)
+          modified.push(hunk.move_path)
+          log.info(`Moved file: ${hunk.path} -> ${hunk.move_path}`)
+        } else {
+          // Regular update
+          await fs.writeFile(hunk.path, fileUpdate.content, "utf-8")
+          modified.push(hunk.path)
+          log.info(`Updated file: ${hunk.path}`)
+        }
+        break
+    }
+  }
+
+  return { added, modified, deleted }
+}
+
+// Main patch application function
+export async function applyPatch(patchText: string): Promise<AffectedPaths> {
+  const { hunks } = parsePatch(patchText)
+  return applyHunksToFiles(hunks)
+}
+
+// Async version of maybeParseApplyPatchVerified
+export async function maybeParseApplyPatchVerified(
+  argv: string[],
+  cwd: string,
+): Promise<
+  | { type: MaybeApplyPatchVerified.Body; action: ApplyPatchAction }
+  | { type: MaybeApplyPatchVerified.CorrectnessError; error: Error }
+  | { type: MaybeApplyPatchVerified.NotApplyPatch }
+> {
+  // Detect implicit patch invocation (raw patch without apply_patch command)
+  if (argv.length === 1) {
+    try {
+      parsePatch(argv[0])
+      return {
+        type: MaybeApplyPatchVerified.CorrectnessError,
+        error: new Error(ApplyPatchError.ImplicitInvocation),
+      }
+    } catch {
+      // Not a patch, continue
+    }
+  }
+
+  const result = maybeParseApplyPatch(argv)
+
+  switch (result.type) {
+    case MaybeApplyPatch.Body:
+      const { args } = result
+      const effectiveCwd = args.workdir ? path.resolve(cwd, args.workdir) : cwd
+      const changes = new Map<string, ApplyPatchFileChange>()
+
+      for (const hunk of args.hunks) {
+        const resolvedPath = path.resolve(
+          effectiveCwd,
+          hunk.type === "update" && hunk.move_path ? hunk.move_path : hunk.path,
+        )
+
+        switch (hunk.type) {
+          case "add":
+            changes.set(resolvedPath, {
+              type: "add",
+              content: hunk.contents,
+            })
+            break
+
+          case "delete":
+            // For delete, we need to read the current content
+            const deletePath = path.resolve(effectiveCwd, hunk.path)
+            try {
+              const content = await fs.readFile(deletePath, "utf-8")
+              changes.set(resolvedPath, {
+                type: "delete",
+                content,
+              })
+            } catch {
+              return {
+                type: MaybeApplyPatchVerified.CorrectnessError,
+                error: new Error(`Failed to read file for deletion: ${deletePath}`),
+              }
+            }
+            break
+
+          case "update":
+            const updatePath = path.resolve(effectiveCwd, hunk.path)
+            try {
+              const fileUpdate = deriveNewContentsFromChunks(updatePath, hunk.chunks)
+              changes.set(resolvedPath, {
+                type: "update",
+                unified_diff: fileUpdate.unified_diff,
+                move_path: hunk.move_path ? path.resolve(effectiveCwd, hunk.move_path) : undefined,
+                new_content: fileUpdate.content,
+              })
+            } catch (error) {
+              return {
+                type: MaybeApplyPatchVerified.CorrectnessError,
+                error: error as Error,
+              }
+            }
+            break
+        }
+      }
+
+      return {
+        type: MaybeApplyPatchVerified.Body,
+        action: {
+          changes,
+          patch: args.patch,
+          cwd: effectiveCwd,
+        },
+      }
+
+    case MaybeApplyPatch.PatchParseError:
+      return {
+        type: MaybeApplyPatchVerified.CorrectnessError,
+        error: result.error,
+      }
+
+    case MaybeApplyPatch.NotApplyPatch:
+      return { type: MaybeApplyPatchVerified.NotApplyPatch }
+  }
+}