Class: Refinement::Changeset

Inherits:
Object
  • Object
show all
Defined in:
lib/refinement/changeset.rb,
lib/refinement/changeset/file_modification.rb

Overview

Represents a set of changes in a repository between a prior revision and the current state

Defined Under Namespace

Classes: FileModification, GitError

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(repository:, modifications:, description: nil) ⇒ Changeset

Returns a new instance of Changeset.



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# File 'lib/refinement/changeset.rb', line 26

def initialize(repository:, modifications:, description: nil)
  @repository = repository
  @modifications = self.class.add_directories(modifications).uniq.freeze
  @description = description

  @modified_paths = {}
  @modifications
    .each { |mod| @modified_paths[mod.path] = mod }
    .each { |mod| @modified_paths[mod.prior_path] ||= mod if mod.prior_path }
  @modified_paths.freeze

  @modified_absolute_paths = {}
  @modified_paths
    .each { |path, mod| @modified_absolute_paths[path.expand_path(repository).freeze] = mod }
  @modified_absolute_paths.freeze
end

Instance Attribute Details

#description ⇒ String (readonly)

Returns a desciption of the changeset.

Returns:

  • (String) —

    a desciption of the changeset



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# File 'lib/refinement/changeset.rb', line 22

def description
  @description
end

#repository ⇒ Pathname (readonly)

Returns the path to the repository.

Returns:

  • (Pathname) —

    the path to the repository



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# File 'lib/refinement/changeset.rb', line 14

def repository
  @repository
end

Class Method Details

.from_git(repository:, base_revision:) ⇒ Changeset

Returns the changes in the given git repository between the given revision and HEAD.

Parameters:

  • repository (Pathname)
  • base_revision (String)

Returns:

  • (Changeset) —

    the changes in the given git repository between the given revision and HEAD

Raises:

  • (ArgumentError) 


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# File 'lib/refinement/changeset.rb', line 143

def self.from_git(repository:, base_revision:)
  raise ArgumentError, "must be given a Pathname for repository, got #{repository.inspect}" unless repository.is_a?(Pathname)
  raise ArgumentError, "must be given a String for base_revision, got #{base_revision.inspect}" unless base_revision.is_a?(String)

  merge_base = git!('merge-base', base_revision, 'HEAD', chdir: repository).strip
  diff = git!('diff', '--raw', '-z', merge_base, chdir: repository)
  modifications = parse_raw_diff(diff, repository: repository, base_revision: merge_base).freeze

  new(repository: repository, modifications: modifications, description: "since #{base_revision}")
end

.parse_raw_diff(diff, repository:, base_revision:) ⇒ Array<FileModification>

Parses the raw diff into FileModification objects

Parameters:

  • diff (String) —

    a diff generated by ‘git diff –raw -z`

  • repository (Pathname) —

    the path to the repository

  • base_revision (String) —

    the base revision the diff was constructed agains

Returns:



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# File 'lib/refinement/changeset.rb', line 174

def self.parse_raw_diff(diff, repository:, base_revision:)
  # since we're null separating the chunks (to avoid dealing with path escaping) we have to reconstruct
  # the chunks into individual diff entries. entries always start with a colon so we can use that to signal if
  # we're on a new entry
  parsed_lines = diff.split("\0").each_with_object([]) do |chunk, lines|
    lines << [] if chunk.start_with?(':')
    lines.last << chunk
  end

  parsed_lines.map do |split_line|
    # change chunk (letter + optional similarity percentage) will always be the last part of first line chunk
    change_chunk = split_line[0].split(/\s/).last

    new_path = Pathname(split_line[2]).freeze if split_line[2]
    old_path = Pathname(split_line[1]).freeze
    prior_path = old_path if new_path
    # new path if one exists, else existing path. new path only exists for rename and copy
    changed_path = new_path || old_path

    change_character = change_chunk[0]
    # returns 0 when a similarity percentage isn't specified by git.
    _similarity = change_chunk[1..3].to_i

    FileModification.new(
      path: changed_path,
      type: CHANGE_CHARACTERS[change_character],
      prior_path: prior_path,
      contents_reader: -> { repository.join(changed_path).read },
      prior_contents_reader: lambda {
        git!('show', "#{base_revision}:#{prior_path || changed_path}", chdir: repository)
      }
    )
  end
end

Instance Method Details

#find_modification_for_glob(absolute_glob:) ⇒ FileModification, Nil

Note:

Will only return a single (arbitrary) matching modification, even if there are multiple modifications that match the glob

Returns the modification for the given absolute glob, or ‘nil` if no files matching the glob were modified.

Parameters:

  • absolute_glob (String) —

    a glob pattern for absolute paths, suitable for an invocation of ‘Dir.glob`

Returns:

  • (FileModification, Nil) —

    the modification for the given absolute glob, or ‘nil` if no files matching the glob were modified



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# File 'lib/refinement/changeset.rb', line 117

def find_modification_for_glob(absolute_glob:)
  absolute_globs = dir_glob_equivalent_patterns(absolute_glob)
  _path, modification = modified_absolute_paths.find do |absolute_path, _modification|
    absolute_globs.any? do |glob|
      File.fnmatch?(glob, absolute_path, File::FNM_CASEFOLD | File::FNM_PATHNAME)
    end
  end
  modification
end

#find_modification_for_path(absolute_path:) ⇒ FileModification, Nil

Returns the changeset for the given absolute path, or ‘nil` if the given path is un-modified.

Parameters:

  • absolute_path (Pathname)

Returns:

  • (FileModification, Nil) —

    the changeset for the given absolute path, or ‘nil` if the given path is un-modified



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# File 'lib/refinement/changeset.rb', line 65

def find_modification_for_path(absolute_path:)
  modified_absolute_paths[absolute_path]
end

#find_modification_for_yaml_keypath(absolute_path:, keypath:) ⇒ FileModification, Nil

Returns a modification and yaml diff for the keypath at the given absolute path, or ‘nil` if the value at the given keypath is un-modified.

Parameters:

  • absolute_path (Pathname)
  • keypath (Array)

Returns:

  • (FileModification, Nil) —

    a modification and yaml diff for the keypath at the given absolute path, or ‘nil` if the value at the given keypath is un-modified



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# File 'lib/refinement/changeset.rb', line 131

def find_modification_for_yaml_keypath(absolute_path:, keypath:)
  return unless (file_modification = find_modification_for_path(absolute_path: absolute_path))

  diff = file_modification.yaml_diff(keypath)
  return unless diff

  [file_modification, diff]
end