module C0::Diff

Overview

C0DIFF parser and applier for atomic multi-file edits.

Format: [FS][GS][US][SUB][US]

• FS starts a new file block
• GS starts a new pattern section within a file
• US separates pattern units (anchor text ↔ replacement regions)
• SUB separates old text from new text within a replacement
• DLE escapes literal control codes

TODO Consider a "replace-all within bounded scope" mode. Two unique sentinel anchors would define a region, and all occurrences within that region would be replaced. Candidate codes: SO/SI (0x0E/0x0F) — "Shift Out/In" to switch into replace-all mode: [GS][SO][SUB][SI] Open questions:

• Is this too liberal? Should there be a max replacement count?
• Or is it better to generate one section per occurrence at a higher tool level, keeping the format strictly exact-match?
• Could also be useful for batch renames (variable/method renaming within a function scope).

Defined in:

c0/diff.cr

Class Method Summary

• .apply(diff_buf : Bytes, files : Hash(String, String)) : Hash(String, String)

  Apply a C0DIFF buffer to a hash of file contents.

• .apply_files(diff_buf : Bytes, base_dir : String = ".") : Nil

  Apply a C0DIFF buffer to files on disk.

• .build(& : DiffBuilder -> ) : Bytes

  Build a C0DIFF document.

• .parse(buf : Bytes) : Array(FileEdit)

  Parse a C0DIFF buffer into a list of file edits.

Class Method Detail