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###	S U B V E R S I O N   T A S K S   A N D   H E L P E R S

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require 'pp'

require 'yaml'

require 'English'

# Strftime format for tags/releases

TAG_TIMESTAMP_FORMAT = '%Y%m%d-%H%M%S'

TAG_TIMESTAMP_PATTERN = /\d{4}\d{2}\d{2}-\d{6}/

RELEASE_VERSION_PATTERN = /\d+\.\d+\.\d+/

DEFAULT_EDITOR = 'vi'

DEFAULT_KEYWORDS = %w[Date Rev Author URL Id]

KEYWORDED_FILEDIRS = %w[applets bin etc lib misc]

KEYWORDED_FILEPATTERN = /^(?:Rakefile|.*\.(?:rb|js|html|template))$/i

COMMIT_MSG_FILE = 'commit-msg.txt'

###

### Subversion-specific Helpers

###

### Return a new tag for the given time

def make_new_tag( time=Time.now )

	return time.strftime( TAG_TIMESTAMP_FORMAT )

end

### Get the subversion information for the current working directory as

### a hash.

def get_svn_info( dir='.' )

	info = IO.read( '|-' ) or exec 'svn', 'info', dir

	return YAML.load( info ) # 'svn info' outputs valid YAML! Yay!

end

### Get a list of the objects registered with subversion under the specified directory and

### return them as an Array of Pathame objects.

def get_svn_filelist( dir='.' )

	list = IO.read( '|-' ) or exec 'svn', 'st', '-v', '--ignore-externals', dir

	# Split into lines, filter out the unknowns, and grab the filenames as Pathnames

	# :FIXME: This will break if we ever put in a file with spaces in its name. This

	# will likely be the least of our worries if we do so, however, so it's not worth

	# the additional complexity to make it handle that case. If we do need that, there's

	# always the --xml output for 'svn st'...

	return list.split( $/ ).

		reject {|line| line =~ /^\?/ }.

		collect {|fn| Pathname(fn[/\S+$/]) }

end

### Return the URL to the repository root for the specified +dir+.

def get_svn_repo_root( dir='.' )

	info = get_svn_info( dir )

	return info['URL'].sub( %r{/trunk$}, '' )

end

### Return the Subversion URL to the given +dir+.

def get_svn_url( dir='.' )

	info = get_svn_info( dir )

	return info['URL']

end

### Return the path of the specified +dir+ under the svn root of the 

### checkout.

def get_svn_path( dir='.' )

	root = get_svn_repo_root( dir )

	url = get_svn_url( dir )

	return url.sub( root + '/', '' )

end

### Return the keywords for the specified array of +files+ as a Hash keyed by filename.

def get_svn_keyword_map( files )

	cmd = ['svn', 'pg', 'svn:keywords', *files]

	# trace "Executing: svn pg svn:keywords " + files.join(' ')

	output = IO.read( '|-' ) or exec( 'svn', 'pg', 'svn:keywords', *files )

	kwmap = {}

	output.split( "\n" ).each do |line|

		next if line !~ /\s+-\s+/

		path, keywords = line.split( /\s+-\s+/, 2 )

		kwmap[ path ] = keywords.split

	end

	return kwmap

end

### Return the latest revision number of the specified +dir+ as an Integer.

def get_svn_rev( dir='.' )

	info = get_svn_info( dir )

	return info['Revision']

end

### Return a list of the entries at the specified Subversion url. If

### no +url+ is specified, it will default to the list in the URL

### corresponding to the current working directory.

def svn_ls( url=nil )

	url ||= get_svn_url()

	list = IO.read( '|-' ) or exec 'svn', 'ls', url

	trace 'svn ls of %s: %p' % [url, list] if $trace

	return [] if list.nil? || list.empty?

	return list.split( $INPUT_RECORD_SEPARATOR )

end

### Return the URL of the latest timestamp in the tags directory.

def get_latest_svn_timestamp_tag

	rooturl = get_svn_repo_root()

	tagsurl = rooturl + '/tags'

	tags = svn_ls( tagsurl ).grep( TAG_TIMESTAMP_PATTERN ).sort

	return nil if tags.nil? || tags.empty?

	return tagsurl + '/' + tags.last

end

### Get a subversion diff of the specified targets and return it. If no targets are

### specified, the current directory will be diffed instead.

def get_svn_diff( *targets )

	targets << BASEDIR if targets.empty?

	trace "Getting svn diff for targets: %p" % [targets]

	log = IO.read( '|-' ) or exec 'svn', 'diff', *(targets.flatten)

	return log

end

### Return the URL of the latest timestamp in the tags directory.

def get_latest_release_tag

	rooturl    = get_svn_repo_root()

	releaseurl = rooturl + '/releases'

	tags = svn_ls( releaseurl ).grep( RELEASE_VERSION_PATTERN ).sort_by do |tag|

		tag.split('.').collect {|i| Integer(i) }

	end

	return nil if tags.empty?

	return releaseurl + '/' + tags.last

end

### Extract a diff from the specified subversion working +dir+, rewrite its

### file lines as Trac links, and return it.

def make_svn_commit_log( dir='.' )

	editor_prog = ENV['EDITOR'] || ENV['VISUAL'] || DEFAULT_EDITOR

	diff = IO.read( '|-' ) or exec 'svn', 'diff'

	fail "No differences." if diff.empty?

	return diff

end

###

### Tasks

###

desc "Subversion tasks"

namespace :svn do

	desc "Copy the HEAD revision of the current trunk/ to tags/ with a " +

		 "current timestamp."

	task :tag do

		svninfo   = get_svn_info()

		tag       = make_new_tag()

		svntrunk  = svninfo['URL']

		svntagdir = svninfo['URL'].sub( %r{trunk$}, 'tags' )

		svntag    = svntagdir + '/' + tag

		desc = "Tagging trunk as #{svntag}"

		ask_for_confirmation( desc ) do

			msg = prompt_with_default( "Commit log: ", "Tagging for code push" )

			run 'svn', 'cp', '-m', msg, svntrunk, svntag

		end

	end

	desc "Copy the most recent tag to releases/#{PKG_VERSION}"

	task :release do

		last_tag    = get_latest_svn_timestamp_tag()

		svninfo     = get_svn_info()

		release     = PKG_VERSION

		svnrel      = svninfo['URL'] + '/releases'

		svnrelease  = svnrel + '/' + release

		if last_tag.nil?

			error "There are no tags in the repository"

			fail

		end

		releases = svn_ls( svnrel )

		trace "Releases: %p" % [releases]

		if releases.include?( release )

			error "Version #{release} already has a branch (#{svnrelease}). Did you mean" +

				"to increment the version in #{PKG_VERSION_FROM}?"

			fail

		else

			trace "No #{svnrel} version currently exists"

		end

		desc = "Release tag\n  #{last_tag}\nto\n  #{svnrelease}"

		ask_for_confirmation( desc ) do

			msg = prompt_with_default( "Commit log: ", "Branching for release" )

			run 'svn', 'cp', '-m', msg, last_tag, svnrelease

		end

	end

	### Task for debugging the #get_target_args helper

	task :show_targets do

		$stdout.puts "Targets from ARGV (%p): %p" % [ARGV, get_target_args()]

	end

	desc "Generate a commit log"

	task :commitlog => [COMMIT_MSG_FILE]

	desc "Show the (pre-edited) commit log for the current directory"

	task :show_commitlog => [COMMIT_MSG_FILE] do

		ask_for_confirmation( "Confirm? " ) do

			args = get_target_args()

			puts get_svn_diff( *args )

		end

	end

	file COMMIT_MSG_FILE do

		args = get_target_args()

		diff = get_svn_diff( *args )

		File.open( COMMIT_MSG_FILE, File::WRONLY|File::EXCL|File::CREAT ) do |fh|

			fh.print( diff )

		end

		editor = ENV['EDITOR'] || ENV['VISUAL'] || DEFAULT_EDITOR

		system editor, COMMIT_MSG_FILE

		unless $?.success?

			fail "Editor exited uncleanly."

		end

	end

	desc "Update from Subversion"

	task :update do

		run 'svn', 'up', '--ignore-externals'

	end

	desc "Check in all the changes in your current working copy"

	task :checkin => ['svn:update', 'coverage:verify', 'svn:fix_keywords', COMMIT_MSG_FILE] do

		targets = get_target_args()

		$deferr.puts '---', File.read( COMMIT_MSG_FILE ), '---'

		ask_for_confirmation( "Continue with checkin?" ) do

			run 'svn', 'ci', '-F', COMMIT_MSG_FILE, targets

			rm_f COMMIT_MSG_FILE

		end

	end

	task :commit => :checkin

	task :ci => :checkin

	task :clean do

		rm_f COMMIT_MSG_FILE

	end

	desc "Check and fix any missing keywords for any files in the project which need them"

	task :fix_keywords do

		log "Checking subversion keywords..."

		paths = get_svn_filelist( BASEDIR ).

			select {|path| path.file? && path.to_s =~ KEYWORDED_FILEPATTERN }

		trace "Looking at %d paths for keywords:\n  %p" % [paths.length, paths]

		kwmap = get_svn_keyword_map( paths )

		buf = ''

		PP.pp( kwmap, buf, 132 )

		trace "keyword map is: %s" % [buf]

		files_needing_fixups = paths.find_all do |path|

			(kwmap[path.to_s] & DEFAULT_KEYWORDS) != DEFAULT_KEYWORDS

		end

		unless files_needing_fixups.empty?

			$deferr.puts "Files needing keyword fixes: ",

				files_needing_fixups.collect {|f|

					"  %s: %s" % [f, kwmap[f] ? kwmap[f].join(' ') : "(no keywords)"]

				}

			ask_for_confirmation( "Will add default keywords to these files." ) do

				run 'svn', 'ps', 'svn:keywords', DEFAULT_KEYWORDS.join(' '), *files_needing_fixups

			end

		else

			log "Keywords are all up to date."

		end

	end

	task :debug_helpers do

		methods = [

			:make_new_tag,

			:get_svn_info,

			:get_svn_repo_root,

			:get_svn_url,

			:get_svn_path,

			:svn_ls,

			:get_latest_svn_timestamp_tag,

		]

		maxlen = methods.collect {|sym| sym.to_s.length }.max

		methods.each do |meth|

			res = send( meth )

			puts "%*s => %p" % [ maxlen, colorize(meth.to_s, :cyan), res ]

		end

	end

end