Merge pull request #1335 from github/1318-local

1318 local

.travis.yml

@@ -1,4 +1,6 @@
 before_install: 
+  - git fetch origin master:master
+  - git fetch origin v2.0.0:v2.0.0
   - sudo apt-get install libicu-dev -y
   - gem update --system 2.1.11
 rvm:

bin/linguist

@@ -5,6 +5,7 @@
 
 require 'linguist/file_blob'
 require 'linguist/repository'
+require 'rugged'
 
 path = ARGV[0] || Dir.pwd
 
@@ -18,7 +19,8 @@ ARGV.shift
 breakdown = true if ARGV[0] == "--breakdown"
 
 if File.directory?(path)
-  repo = Linguist::Repository.from_directory(path)
+  rugged = Rugged::Repository.new(path)
+  repo = Linguist::Repository.new(rugged, rugged.head.target_id)
   repo.languages.sort_by { |_, size| size }.reverse.each do |language, size|
     percentage = ((size / repo.size.to_f) * 100)
     percentage = sprintf '%.2f' % percentage

github-linguist.gemspec

@@ -17,6 +17,7 @@ Gem::Specification.new do |s|
   s.add_dependency 'escape_utils',    '~> 1.0.1'
   s.add_dependency 'mime-types',      '~> 1.19'
   s.add_dependency 'pygments.rb',     '~> 0.6.0'
+  s.add_dependency 'rugged',          '~> 0.21.0'
 
   s.add_development_dependency 'json'
   s.add_development_dependency 'mocha'

lib/linguist/blob_helper.rb

@@ -313,15 +313,7 @@ def generated?
     #
     # Returns a Language or nil if none is detected
     def language
-      return @language if defined? @language
-
-      if defined?(@data) && @data.is_a?(String)
-        data = @data
-      else
-        data = lambda { (binary_mime_type? || binary?) ? "" : self.data }
-      end
-
-      @language = Language.detect(name.to_s, data, mode)
+      @language ||= Language.detect(self)
     end
 
     # Internal: Get the lexer of the blob.

lib/linguist/language.rb

@@ -92,18 +92,17 @@ def self.create(attributes = {})
 
     # Public: Detects the Language of the blob.
     #
-    # name - String filename
-    # data - String blob data. A block also maybe passed in for lazy
-    #        loading. This behavior is deprecated and you should always
-    #        pass in a String.
-    # mode - Optional String mode (defaults to nil)
+    # blob - an object that implements the Linguist `Blob` interface;
+    #       see Linguist::LazyBlob and Linguist::FileBlob for examples
     #
     # Returns Language or nil.
-    def self.detect(name, data, mode = nil)
+    def self.detect(blob)
+      name = blob.name.to_s
+
       # A bit of an elegant hack. If the file is executable but extensionless,
       # append a "magic" extension so it can be classified with other
       # languages that have shebang scripts.
-      if File.extname(name).empty? && mode && (mode.to_i(8) & 05) == 05
+      if File.extname(name).empty? && blob.mode && (blob.mode.to_i(8) & 05) == 05
         name += ".script!"
       end
 
@@ -114,7 +113,7 @@ def self.detect(name, data, mode = nil)
       # extension at all, in the case of extensionless scripts), we need to continue
       # our detection work
       if possible_languages.length > 1
-        data = data.call() if data.respond_to?(:call)
+        data = blob.data
         possible_language_names = possible_languages.map(&:name)
 
         # Don't bother with emptiness

lib/linguist/lazy_blob.rb

@@ -0,0 +1,37 @@
+require 'linguist/blob_helper'
+require 'rugged'
+
+module Linguist
+  class LazyBlob
+    include BlobHelper
+
+    MAX_SIZE = 128 * 1024
+
+    attr_reader :repository
+    attr_reader :oid
+    attr_reader :name
+    attr_reader :mode
+
+    def initialize(repo, oid, name, mode = nil)
+      @repository = repo
+      @oid = oid
+      @name = name
+      @mode = mode
+    end
+
+    def data
+      load_blob!
+      @data
+    end
+
+    def size
+      load_blob!
+      @size
+    end
+
+    protected
+    def load_blob!
+      @data, @size = Rugged::Blob.to_buffer(repository, oid, MAX_SIZE) if @data.nil?
+    end
+  end
+end

lib/linguist/repository.rb

@@ -1,4 +1,5 @@
-require 'linguist/file_blob'
+require 'linguist/lazy_blob'
+require 'rugged'
 
 module Linguist
   # A Repository is an abstraction of a Grit::Repo or a basic file
@@ -7,100 +8,146 @@ module Linguist
   # Its primary purpose is for gathering language statistics across
   # the entire project.
   class Repository
-    # Public: Initialize a new Repository from a File directory
+    attr_reader :repository
+
+    # Public: Create a new Repository based on the stats of
+    # an existing one
+    def self.incremental(repo, commit_oid, old_commit_oid, old_stats)
+      repo = self.new(repo, commit_oid)
+      repo.load_existing_stats(old_commit_oid, old_stats)
+      repo
+    end
+
+    # Public: Initialize a new Repository to be analyzed for language
+    # data
     #
-    # base_path - A path String
+    # repo - a Rugged::Repository object
+    # commit_oid - the sha1 of the commit that will be analyzed;
+    #              this is usually the master branch
     #
     # Returns a Repository
-    def self.from_directory(base_path)
-      new Dir["#{base_path}/**/*"].
-        select { |f| File.file?(f) }.
-        map { |path| FileBlob.new(path, base_path) }
+    def initialize(repo, commit_oid)
+      @repository = repo
+      @commit_oid = commit_oid
+
+      raise TypeError, 'commit_oid must be a commit SHA1' unless commit_oid.is_a?(String)
     end
 
-    # Public: Initialize a new Repository
+    # Public: Load the results of a previous analysis on this repository
+    # to speed up the new scan.
     #
-    # enum - Enumerator that responds to `each` and
-    #        yields Blob objects
+    # The new analysis will be performed incrementally as to only take
+    # into account the file changes since the last time the repository
+    # was scanned
     #
-    # Returns a Repository
-    def initialize(enum)
-      @enum = enum
-      @computed_stats = false
-      @language = @size = nil
-      @sizes = Hash.new { 0 }
-      @file_breakdown = Hash.new { |h,k| h[k] = Array.new }
+    # old_commit_oid - the sha1 of the commit that was previously analyzed
+    # old_stats - the result of the previous analysis, obtained by calling
+    #             Repository#cache on the old repository
+    #
+    # Returns nothing
+    def load_existing_stats(old_commit_oid, old_stats)
+      @old_commit_oid = old_commit_oid
+      @old_stats = old_stats
+      nil
     end
 
     # Public: Returns a breakdown of language stats.
     #
     # Examples
     #
-    #   # => { Language['Ruby'] => 46319,
-    #          Language['JavaScript'] => 258 }
+    #   # => { 'Ruby' => 46319,
+    #          'JavaScript' => 258 }
     #
-    # Returns a Hash of Language keys and Integer size values.
+    # Returns a Hash of language names and Integer size values.
     def languages
-      compute_stats
-      @sizes
+      @sizes ||= begin
+        sizes = Hash.new { 0 }
+        cache.each do |_, (language, size)|
+          sizes[language] += size
+        end
+        sizes
+      end
     end
 
     # Public: Get primary Language of repository.
     #
-    # Returns a Language
+    # Returns a language name
     def language
-      compute_stats
-      @language
+      @language ||= begin
+        primary = languages.max_by { |(_, size)| size }
+        primary && primary[0]
+      end
     end
 
     # Public: Get the total size of the repository.
     #
     # Returns a byte size Integer
     def size
-      compute_stats
-      @size
+      @size ||= languages.inject(0) { |s,(_,v)| s + v }
     end
 
     # Public: Return the language breakdown of this repository by file
+    #
+    # Returns a map of language names => [filenames...]
     def breakdown_by_file
-      compute_stats
-      @file_breakdown
+      @file_breakdown ||= begin
+        breakdown = Hash.new { |h,k| h[k] = Array.new }
+        cache.each do |filename, (language, _)|
+          breakdown[language] << filename
+        end
+        breakdown
+      end
     end
 
-    # Internal: Compute language breakdown for each blob in the Repository.
+    # Public: Return the cached results of the analysis
     #
-    # Returns nothing
-    def compute_stats
-      return if @computed_stats
+    # This is a per-file breakdown that can be passed to other instances
+    # of Linguist::Repository to perform incremental scans
+    #
+    # Returns a map of filename => [language, size]
+    def cache
+      @cache ||= begin
+        if @old_commit_oid == @commit_oid
+          @old_stats
+        else
+          compute_stats(@old_commit_oid, @commit_oid, @old_stats)
+        end
+      end
+    end
 
-      @enum.each do |blob|
-        # Skip files that are likely binary
-        next if blob.likely_binary?
+    protected
+    def compute_stats(old_commit_oid, commit_oid, cache = nil)
+      file_map = cache ? cache.dup : {}
+      old_tree = old_commit_oid && Rugged::Commit.lookup(repository, old_commit_oid).tree
+      new_tree = Rugged::Commit.lookup(repository, commit_oid).tree
 
-        # Skip vendored or generated blobs
-        next if blob.vendored? || blob.generated? || blob.language.nil?
+      diff = Rugged::Tree.diff(repository, old_tree, new_tree)
 
-        # Only include programming languages and acceptable markup languages
-        if blob.language.type == :programming || Language.detectable_markup.include?(blob.language.name)
+      diff.each_delta do |delta|
+        old = delta.old_file[:path]
+        new = delta.new_file[:path]
 
-          # Build up the per-file breakdown stats
-          @file_breakdown[blob.language.group.name] << blob.name
+        file_map.delete(old)
+        next if delta.binary
 
-          @sizes[blob.language.group] += blob.size
-        end
-      end
+        if [:added, :modified].include? delta.status
+          # Skip submodules
+          mode = delta.new_file[:mode]
+          next if (mode & 040000) != 0
 
-      # Compute total size
-      @size = @sizes.inject(0) { |s,(_,v)| s + v }
+          blob = Linguist::LazyBlob.new(repository, delta.new_file[:oid], new, mode.to_s(8))
 
-      # Get primary language
-      if primary = @sizes.max_by { |(_, size)| size }
-        @language = primary[0]
-      end
+          # Skip vendored or generated blobs
+          next if blob.vendored? || blob.generated? || blob.language.nil?
 
-      @computed_stats = true
+          # Only include programming languages and acceptable markup languages
+          if blob.language.type == :programming || Language.detectable_markup.include?(blob.language.name)
+            file_map[new] = [blob.language.group.name, blob.size]
+          end
+        end
+      end
 
-      nil
+      file_map
     end
   end
 end

lib/linguist/version.rb

@@ -1,3 +1,3 @@
 module Linguist
-  VERSION = "2.12.0"
+  VERSION = "3.0.0"
 end

test/test_heuristics.rb

@@ -1,6 +1,7 @@
 require 'linguist/heuristics'
 require 'linguist/language'
 require 'linguist/samples'
+require 'linguist/file_blob'
 
 require 'test/unit'
 
@@ -35,7 +36,8 @@ def test_cpp_by_heuristics
   end
 
   def test_detect_still_works_if_nothing_matches
-    match = Language.detect("Hello.m", fixture("Objective-C/hello.m"))
+    blob = Linguist::FileBlob.new(File.join(samples_path, "Objective-C/hello.m"))
+    match = Language.detect(blob)
     assert_equal Language["Objective-C"], match
   end