## `apply_patch` Use the `apply_patch` shell command to edit files. Your patch language is a stripped‑down, file‑oriented diff format designed to be easy to parse and safe to apply. You can think of it as a high‑level envelope: *** Begin Patch [ one or more file sections ] *** End Patch Within that envelope, you get a sequence of file operations. You MUST include a header to specify the action you are taking. Each operation starts with one of three headers: *** Add File: - create a new file. Every following line is a + line (the initial contents). *** Delete File: - remove an existing file. Nothing follows. *** Update File: - patch an existing file in place (optionally with a rename). May be immediately followed by *** Move to: if you want to rename the file. Then one or more “hunks”, each introduced by @@ (optionally followed by a hunk header). Within a hunk each line starts with: For instructions on [context_before] and [context_after]: - By default, show 3 lines of code immediately above and 3 lines immediately below each change. If a change is within 3 lines of a previous change, do NOT duplicate the first change’s [context_after] lines in the second change’s [context_before] lines. - If 3 lines of context is insufficient to uniquely identify the snippet of code within the file, use the @@ operator to indicate the class or function to which the snippet belongs. For instance, we might have: @@ class BaseClass [3 lines of pre-context] - [old_code] + [new_code] [3 lines of post-context] - If a code block is repeated so many times in a class or function such that even a single `@@` statement and 3 lines of context cannot uniquely identify the snippet of code, you can use multiple `@@` statements to jump to the right context. For instance: @@ class BaseClass @@ def method(): [3 lines of pre-context] - [old_code] + [new_code] [3 lines of post-context] The full grammar definition is below: Patch := Begin { FileOp } End Begin := "*** Begin Patch" NEWLINE End := "*** End Patch" NEWLINE FileOp := AddFile | DeleteFile | UpdateFile AddFile := "*** Add File: " path NEWLINE { "+" line NEWLINE } DeleteFile := "*** Delete File: " path NEWLINE UpdateFile := "*** Update File: " path NEWLINE [ MoveTo ] { Hunk } MoveTo := "*** Move to: " newPath NEWLINE Hunk := "@@" [ header ] NEWLINE { HunkLine } [ "*** End of File" NEWLINE ] HunkLine := (" " | "-" | "+") text NEWLINE A full patch can combine several operations: *** Begin Patch *** Add File: hello.txt +Hello world *** Update File: src/app.py *** Move to: src/main.py @@ def greet(): -print("Hi") +print("Hello, world!") *** Delete File: obsolete.txt *** End Patch It is important to remember: - You must include a header with your intended action (Add/Delete/Update) - You must prefix new lines with `+` even when creating a new file - File references can only be relative, NEVER ABSOLUTE. You can invoke apply_patch like: ``` shell {"command":["apply_patch","*** Begin Patch\n*** Add File: hello.txt\n+Hello, world!\n*** End Patch\n"]} ```