Merge branch 'PR/197'

Closes #197, #185, #196

.gitattributes

@@ -0,0 +1,2 @@
+# Set the default behavior, in case people don't have core.autocrlf set.
+* text=auto

.gitignore

@@ -1,2 +1,4 @@
+*.orig
 *.pyc
 .dotest
+.idea/

README-SUBMODULES.md

@@ -0,0 +1,75 @@
+# How to convert Mercurial Repositories with subrepos
+
+## Introduction
+
+hg-fast-export supports migrating mercurial subrepositories in the
+repository being converted into git submodules in the converted repository.
+
+Git submodules must be git repositories while mercurial's subrepositories can
+be git, mercurial or subversion repositories. hg-fast-export will handle any
+git subrepositories automatically, any other kinds must first be converted
+to git repositories. Currently hg-fast-export does not support the conversion
+of subversion subrepositories. The rest of this page covers the conversion of
+mercurial subrepositories which require some manual steps:
+
+The first step for mercurial subrepositories involves converting the
+subrepository into a git repository using hg-fast-export.  When all
+subrepositories have been converted, a mapping file that maps the mercurial
+subrepository path to a converted git submodule path must be created. The
+format for this file is:
+
+"<mercurial subrepo path>"="<git submodule path>"
+"<mercurial subrepo path2>"="<git submodule path2>"
+...
+
+The path of this mapping file is then provided with the --subrepo-map
+command line option.
+
+## Example
+
+Example mercurial repo folder structure (~/mercurial):
+    src/...
+    subrepo/subrepo1
+    subrepo/subrepo2
+
+### Setup
+Create an empty new folder where all the converted git modules will be imported:
+    mkdir ~/imported-gits
+    cd ~/imported-gits
+
+### Convert all submodules to git:
+    mkdir submodule1
+    cd submodule1
+    git init
+    hg-fast-export.sh -r ~/mercurial/subrepo1
+    cd ..
+    mkdir submodule2
+    cd submodule2
+    git init
+    hg-fast-export.sh -r ~/mercurial/subrepo2
+
+### Create mapping file
+    cd ~/imported-gits
+    cat > submodule-mappings << EOF
+    "subrepo/subrepo1"="../submodule1"
+    "subrepo/subrepo2"="../submodule2"
+    EOF
+
+### Convert main repository
+    cd ~/imported-gits
+    mkdir git-main-repo
+    cd git-main-repo
+    git init
+    hg-fast-export.sh -r ~/mercurial --subrepo-map=../submodule-mappings
+
+### Result
+The resulting repository will now contain the subrepo/subrepo1 and
+subrepo/subrepo1 submodules. The created .gitmodules file will look
+like:
+
+    [submodule "subrepo/subrepo1"]
+          path = subrepo/subrepo1
+          url = ../submodule1
+    [submodule "subrepo/subrepo2"]
+          path = subrepo/subrepo2
+          url = ../submodule2

README.md

@@ -4,14 +4,38 @@ hg-fast-export.(sh|py) - mercurial to git converter using git-fast-import
 Legal
 -----
 
-Most hg-* scripts are licensed under the [MIT license]
-(http://www.opensource.org/licenses/mit-license.php) and were written
+Most hg-* scripts are licensed under the [MIT license] and were written
 by Rocco Rutte <pdmef@gmx.net> with hints and help from the git list and
 \#mercurial on freenode. hg-reset.py is licensed under GPLv2 since it
 copies some code from the mercurial sources.
 
 The current maintainer is Frej Drejhammar <frej.drejhammar@gmail.com>.
 
+[MIT license]: http://www.opensource.org/licenses/mit-license.php
+
+Support
+-------
+
+If you have problems with hg-fast-export or have found a bug, please
+create an issue at the [github issue tracker]. Before creating a new
+issue, check that your problem has not already been addressed in an
+already closed issue. Do not contact the maintainer directly unless
+you want to report a security bug. That way the next person having the
+same problem can benefit from the time spent solving the problem the
+first time.
+
+[github issue tracker]: https://github.com/frej/fast-export/issues
+
+System Requirements
+-------------------
+
+This project depends on Python 2.7 and the Mercurial >= 4.6
+package. If Python is not installed, install it before proceeding. The
+Mercurial package can be installed with `pip install mercurial`.
+
+On windows the bash that comes with "Git for Windows" is known to work
+well.
+
 Usage
 -----
 
@@ -21,7 +45,8 @@ Using hg-fast-export is quite simple for a mercurial repository <repo>:
 mkdir repo-git # or whatever
 cd repo-git
 git init
-hg-fast-export.sh -r <repo>
+hg-fast-export.sh -r <local-repo>
+git checkout HEAD
 ```
 
 Please note that hg-fast-export does not automatically check out the
@@ -53,12 +78,18 @@ As mercurial appears to be much less picky about the syntax of the
 author information than git, an author mapping file can be given to
 hg-fast-export to fix up malformed author strings. The file is
 specified using the -A option. The file should contain lines of the
-form `FromAuthor=ToAuthor`. The example authors.map below will
-translate `User <garbage<user@example.com>` to `User <user@example.com>`.
+form `"<key>"="<value>"`. Inside the key and value strings, all escape
+sequences understood by the python `string_escape` encoding are
+supported. (Versions of fast-export prior to v171002 had a different
+syntax, the old syntax can be enabled by the flag
+`--mappings-are-raw`.)
+
+The example authors.map below will translate `User
+<garbage<tab><user@example.com>` to `User <user@example.com>`.
 
 ```
 -- Start of authors.map --
-User <garbage<user@example.com>=User <user@example.com>
+"User <garbage\t<user@example.com>"="User <user@example.com>"
 -- End of authors.map --
 ```
 
@@ -70,6 +101,94 @@ name the -B and -T options allow a mapping file to be specified to
 rename branches and tags (respectively). The syntax of the mapping
 file is the same as for the author mapping.
 
+When the -B and -T flags are used, you will probably want to use the
+-n flag to disable the built-in (broken in many cases) sanitizing of
+branch/tag names. In the future -n will become the default, but in
+order to not break existing incremental conversions, the default
+remains with the old behavior.
+
+By default, the `default` mercurial branch is renamed to the `master` 
+branch on git. If your mercurial repo contains both `default` and 
+`master` branches, you'll need to override this behavior. Use
+`-M <newName>` to specify what name to give the `default` branch.
+
+Content filtering
+-----------------
+
+hg-fast-export supports filtering the content of exported files.
+The filter is supplied to the --filter-contents option. hg-fast-export
+runs the filter for each exported file, pipes its content to the filter's
+standard input, and uses the filter's standard output in place
+of the file's original content. The prototypical use of this feature
+is to convert line endings in text files from CRLF to git's preferred LF:
+
+```
+-- Start of crlf-filter.sh --
+#!/bin/sh
+# $1 = pathname of exported file relative to the root of the repo
+# $2 = Mercurial's hash of the file
+# $3 = "1" if Mercurial reports the file as binary, otherwise "0"
+
+if [ "$3" == "1" ]; then cat; else dos2unix; fi
+-- End of crlf-filter.sh --
+```
+
+
+Plugins
+-----------------
+
+hg-fast-export supports plugins to manipulate the file data and commit
+metadata. The plugins are enabled with the --plugin option. The value
+of said option is a plugin name (by folder in the plugins directory),
+and optionally, and equals-sign followed by an initialization string.
+
+There is a readme accompanying each of the bundled plugins, with a
+description of the usage. To create a new plugin, one must simply
+add a new folder under the `plugins` directory, with the name of the
+new plugin. Inside, there must be an `__init__.py` file, which contains
+at a minimum:
+
+```
+def build_filter(args):
+    return Filter(args)
+
+class Filter:
+    def __init__(self, args):
+        pass
+        #Or don't pass, if you want to do some init code here
+```
+
+Beyond the boilerplate initialization, you can see the two different
+defined filter methods in the [dos2unix](./plugins/dos2unix) and
+[branch_name_in_commit](./plugins/branch_name_in_commit) plugins.
+
+```
+commit_data = {'branch': branch, 'parents': parents, 'author': author, 'desc': desc}
+
+def commit_message_filter(self,commit_data):
+```
+The `commit_message_filter` method is called for each commit, after parsing
+from hg, but before outputting to git. The dictionary `commit_data` contains the
+above attributes about the commit, and can be modified by any filter. The
+values in the dictionary after filters have been run are used to create the git
+commit.
+
+```
+file_data = {'filename':filename,'file_ctx':file_ctx,'d':d}
+
+def file_data_filter(self,file_data):
+```
+The `file_data_filter` method is called for each file within each commit.
+The dictionary `file_data` contains the above attributes about the file, and
+can be modified by any filter. `file_ctx` is the filecontext from the
+mercurial python library.  After all filters have been run, the values
+are used to add the file to the git commit.
+
+Submodules
+----------
+See README-SUBMODULES.md for how to convert subrepositories into git
+submodules.
+
 Notes/Limitations
 -----------------
 
@@ -77,6 +196,11 @@ hg-fast-export supports multiple branches but only named branches with
 exactly one head each. Otherwise commits to the tip of these heads
 within the branch will get flattened into merge commits.
 
+hg-fast-export will ignore any files or directories tracked by mercurial
+called `.git`, and will print a warning if it encounters one. Git cannot
+track such files or directories. This is not to be confused with submodules,
+which are described in README-SUBMODULES.md.
+
 As each git-fast-import run creates a new pack file, it may be
 required to repack the repository quite often for incremental imports
 (especially when importing a small number of changesets per
@@ -99,6 +223,54 @@ saw never get modified.
 Submitting Patches
 ------------------
 
-Please use the issue-tracker at github
-https://github.com/frej/fast-export to report bugs and submit
-patches.
+Please use the [issue-tracker](https://github.com/frej/fast-export) at
+github to report bugs and submit patches.
+
+Please read
+[https://chris.beams.io/posts/git-commit/](https://chris.beams.io/posts/git-commit/)
+on how to write a good commit message before submitting a pull request
+for review. Although the article recommends at most 50 characters for
+the subject, up to 72 characters are frequently accepted for
+fast-export.
+
+Frequent Problems
+=================
+
+* git fast-import crashes with: `error: cannot lock ref 'refs/heads/...`
+
+  Branch names in git behave as file names (as they are just files and
+  sub-directories under `refs/heads/`, and a path cannot name both a
+  file and a directory, i.e. the branches `a` and `a/b` can never
+  exist at the same time in a git repo.
+
+  Use a mapping file to rename the troublesome branch names.
+
+* `Branch [<branch-name>] modified outside hg-fast-export` but I have
+  not touched the repo!
+
+  If you are running fast-export on a case-preserving but
+  case-insensitive file system (Windows and OSX), this will make git
+  treat `A` and `a` as the same branch. The solution is to use a
+  mapping file to rename branches which only differ in case.
+
+* My mapping file does not seem to work when I rename the branch `git
+  fast-import` crashes on!
+
+  fast-export (imperfectly) mangles branch names it thinks won't be
+  valid. The mechanism cannot be removed as it would break already
+  existing incremental imports that expects it. When fast export
+  mangles a name, it prints out a warning of the form `Warning:
+  sanitized branch [<unmangled>] to [<mangled>]`. If `git fast-import`
+  crashes on `<mangled>`, you need to put `<unmangled>` into the
+  mapping file.
+
+* fast-import mangles valid git branch names which I have remapped!
+
+  Use the `-n` flag to hg-fast-export.sh.
+
+* `git status` reports that all files are scheduled for deletion after
+  the initial conversion.
+
+  By design fast export does not touch your working directory, so to
+  git it looks like you have deleted all files, when in fact they have
+  never been checked out. Just do a checkout of the branch you want.

hg-fast-export.py

@@ -1,15 +1,17 @@
-#!/usr/bin/env python
+#!/usr/bin/env python2
 
 # Copyright (c) 2007, 2008 Rocco Rutte <pdmef@gmx.net> and others.
 # License: MIT <http://www.opensource.org/licenses/mit-license.php>
 
 from mercurial import node
+from mercurial.scmutil import revsymbol
 from hg2git import setup_repo,fixup_user,get_branch,get_changeset
 from hg2git import load_cache,save_cache,get_git_sha1,set_default_branch,set_origin_name
 from optparse import OptionParser
 import re
 import sys
 import os
+import pluginloader
 
 if sys.platform == "win32":
   # On Windows, sys.stdout is initially opened in text mode, which means that
@@ -26,6 +28,13 @@ cfg_checkpoint_count=0
 # write some progress message every this many file contents written
 cfg_export_boundary=1000
 
+subrepo_cache={}
+submodule_mappings=None
+
+# True if fast export should automatically try to sanitize
+# author/branch/tag names.
+auto_sanitize = None
+
 def gitmode(flags):
   return 'l' in flags and '120000' or 'x' in flags and '100755' or '100644'
 
@@ -78,7 +87,7 @@ def get_filechanges(repo,revision,parents,mleft):
   l,c,r=[],[],[]
   for p in parents:
     if p<0: continue
-    mright=repo.changectx(p).manifest()
+    mright=revsymbol(repo,str(p)).manifest()
     l,c,r=split_dict(mleft,mright,l,c,r)
   l.sort()
   c.sort()
@@ -122,19 +131,93 @@ def get_author(logmessage,committer,authors):
       return r
   return committer
 
-def export_file_contents(ctx,manifest,files,hgtags,encoding=''):
+def remove_gitmodules(ctx):
+  """Removes all submodules of ctx parents"""
+  # Removing all submoduies coming from all parents is safe, as the submodules
+  # of the current commit will be re-added below. A possible optimization would
+  # be to only remove the submodules of the first parent.
+  for parent_ctx in ctx.parents():
+    for submodule in parent_ctx.substate.keys():
+      wr('D %s' % submodule)
+  wr('D .gitmodules')
+
+def refresh_git_submodule(name,subrepo_info):
+  wr('M 160000 %s %s' % (subrepo_info[1],name))
+  sys.stderr.write("Adding/updating submodule %s, revision %s\n"
+                   % (name,subrepo_info[1]))
+  return '[submodule "%s"]\n\tpath = %s\n\turl = %s\n' % (name,name,
+    subrepo_info[0])
+
+def refresh_hg_submodule(name,subrepo_info):
+  gitRepoLocation=submodule_mappings[name] + "/.git"
+
+  # Populate the cache to map mercurial revision to git revision
+  if not name in subrepo_cache:
+    subrepo_cache[name]=(load_cache(gitRepoLocation+"/hg2git-mapping"),
+                         load_cache(gitRepoLocation+"/hg2git-marks",
+                                    lambda s: int(s)-1))
+
+  (mapping_cache,marks_cache)=subrepo_cache[name]
+  subrepo_hash=subrepo_info[1]
+  if subrepo_hash in mapping_cache:
+    revnum=mapping_cache[subrepo_hash]
+    gitSha=marks_cache[int(revnum)]
+    wr('M 160000 %s %s' % (gitSha,name))
+    sys.stderr.write("Adding/updating submodule %s, revision %s->%s\n"
+                     % (name,subrepo_hash,gitSha))
+    return '[submodule "%s"]\n\tpath = %s\n\turl = %s\n' % (name,name,
+      submodule_mappings[name])
+  else:
+    sys.stderr.write("Warning: Could not find hg revision %s for %s in git %s\n" %
+      (subrepo_hash,name,gitRepoLocation))
+    return ''
+
+def refresh_gitmodules(ctx):
+  """Updates list of ctx submodules according to .hgsubstate file"""
+  remove_gitmodules(ctx)
+  gitmodules=""
+  # Create the .gitmodules file and all submodules
+  for name,subrepo_info in ctx.substate.items():
+    if subrepo_info[2]=='git':
+      gitmodules+=refresh_git_submodule(name,subrepo_info)
+    elif submodule_mappings and name in submodule_mappings:
+      gitmodules+=refresh_hg_submodule(name,subrepo_info)
+
+  if len(gitmodules):
+    wr('M 100644 inline .gitmodules')
+    wr('data %d' % (len(gitmodules)+1))
+    wr(gitmodules)
+
+def export_file_contents(ctx,manifest,files,hgtags,encoding='',plugins={}):
   count=0
   max=len(files)
+  is_submodules_refreshed=False
   for file in files:
+    if not is_submodules_refreshed and (file=='.hgsub' or file=='.hgsubstate'):
+      is_submodules_refreshed=True
+      refresh_gitmodules(ctx)
     # Skip .hgtags files. They only get us in trouble.
     if not hgtags and file == ".hgtags":
       sys.stderr.write('Skip %s\n' % (file))
       continue
-    d=ctx.filectx(file).data()
     if encoding:
       filename=file.decode(encoding).encode('utf8')
     else:
       filename=file
+    if '.git' in filename.split(os.path.sep):
+      sys.stderr.write('Ignoring file %s which cannot be tracked by git\n' % filename)
+      continue
+    file_ctx=ctx.filectx(file)
+    d=file_ctx.data()
+
+    if plugins and plugins['file_data_filters']:
+      file_data = {'filename':filename,'file_ctx':file_ctx,'data':d}
+      for filter in plugins['file_data_filters']:
+        filter(file_data)
+      d=file_data['data']
+      filename=file_data['filename']
+      file_ctx=file_data['file_ctx']
+
     wr('M %s inline %s' % (gitmode(manifest.flags(file)),
                            strip_leading_slash(filename)))
     wr('data %d' % len(d)) # had some trouble with size()
@@ -153,14 +236,21 @@ def sanitize_name(name,what="branch", mapping={}):
   # modifying names which previously were not touched it will break
   # preexisting setups which are doing incremental imports.
   #
-  # Use the -B and -T options to mangle branch and tag names
-  # instead. If you have a source repository where this is too much
-  # work to do manually, write a tool that does it for you.
+  # Fast-export tries to not inflict arbitrary naming policy on the
+  # user, instead it aims to provide mechanisms allowing the user to
+  # apply their own policy. Therefore do not add a transform which can
+  # already be implemented with the -B and -T options to mangle branch
+  # and tag names. If you have a source repository where this is too
+  # much work to do manually, write a tool that does it for you.
+  #
 
   def dot(name):
+    if not name: return name
     if name[0] == '.': return '_'+name[1:]
     return name
 
+  if not auto_sanitize:
+    return mapping.get(name,name)
   n=mapping.get(name,name)
   p=re.compile('([[ ~^:?\\\\*]|\.\.)')
   n=p.sub('_', n)
@@ -179,7 +269,8 @@ def strip_leading_slash(filename):
   return filename
 
 def export_commit(ui,repo,revision,old_marks,max,count,authors,
-                  branchesmap,sob,brmap,hgtags,encoding='',fn_encoding=''):
+                  branchesmap,sob,brmap,hgtags,encoding='',fn_encoding='',
+                  plugins={}):
   def get_branchname(name):
     if brmap.has_key(name):
       return brmap[name]
@@ -188,10 +279,22 @@ def export_commit(ui,repo,revision,old_marks,max,count,authors,
     return n
 
   (revnode,_,user,(time,timezone),files,desc,branch,_)=get_changeset(ui,repo,revision,authors,encoding)
+  if repo[revnode].hidden():
+    return count
 
   branch=get_branchname(branch)
 
   parents = [p for p in repo.changelog.parentrevs(revision) if p >= 0]
+  author = get_author(desc,user,authors)
+
+  if plugins and plugins['commit_message_filters']:
+    commit_data = {'branch': branch, 'parents': parents, 'author': author, 'desc': desc}
+    for filter in plugins['commit_message_filters']:
+      filter(commit_data)
+    branch = commit_data['branch']
+    parents = commit_data['parents']
+    author = commit_data['author']
+    desc = commit_data['desc']
 
   if len(parents)==0 and revision != 0:
     wr('reset refs/heads/%s' % branch)
@@ -199,13 +302,13 @@ def export_commit(ui,repo,revision,old_marks,max,count,authors,
   wr('commit refs/heads/%s' % branch)
   wr('mark :%d' % (revision+1))
   if sob:
-    wr('author %s %d %s' % (get_author(desc,user,authors),time,timezone))
+    wr('author %s %d %s' % (author,time,timezone))
   wr('committer %s %d %s' % (user,time,timezone))
   wr('data %d' % (len(desc)+1)) # wtf?
   wr(desc)
   wr()
 
-  ctx=repo.changectx(str(revision))
+  ctx=revsymbol(repo,str(revision))
   man=ctx.manifest()
   added,changed,removed,type=[],[],[],''
 
@@ -220,8 +323,8 @@ def export_commit(ui,repo,revision,old_marks,max,count,authors,
       # later non-merge revision: feed in changed manifest
       # if we have exactly one parent, just take the changes from the
       # manifest without expensively comparing checksums
-      f=repo.status(repo.lookup(parents[0]),revnode)[:3]
-      added,changed,removed=f[1],f[0],f[2]
+      f=repo.status(parents[0],revnode)
+      added,changed,removed=f.added,f.modified,f.removed
       type='simple delta'
     else: # a merge with two parents
       wr('merge %s' % revnum_to_revref(parents[1], old_marks))
@@ -234,20 +337,24 @@ def export_commit(ui,repo,revision,old_marks,max,count,authors,
   sys.stderr.write('%s: Exporting %s revision %d/%d with %d/%d/%d added/changed/removed files\n' %
       (branch,type,revision+1,max,len(added),len(changed),len(removed)))
 
-  if fn_encoding:
-    removed=[r.decode(fn_encoding).encode('utf8') for r in removed]
+  for filename in removed:
+    if fn_encoding:
+      filename=filename.decode(fn_encoding).encode('utf8')
+    filename=strip_leading_slash(filename)
+    if filename=='.hgsub':
+      remove_gitmodules(ctx)
+    wr('D %s' % filename)
 
-  removed=[strip_leading_slash(x) for x in removed]
-
-  map(lambda r: wr('D %s' % r),removed)
-  export_file_contents(ctx,man,added,hgtags,fn_encoding)
-  export_file_contents(ctx,man,changed,hgtags,fn_encoding)
+  export_file_contents(ctx,man,added,hgtags,fn_encoding,plugins)
+  export_file_contents(ctx,man,changed,hgtags,fn_encoding,plugins)
   wr()
 
   return checkpoint(count)
 
 def export_note(ui,repo,revision,count,authors,encoding,is_first):
   (revnode,_,user,(time,timezone),_,_,_,_)=get_changeset(ui,repo,revision,authors,encoding)
+  if repo[revnode].hidden():
+    return count
 
   parents = [p for p in repo.changelog.parentrevs(revision) if p >= 0]
 
@@ -257,7 +364,7 @@ def export_note(ui,repo,revision,count,authors,encoding,is_first):
   if is_first:
     wr('from refs/notes/hg^0')
   wr('N inline :%d' % (revision+1))
-  hg_hash=repo.changectx(str(revision)).hex()
+  hg_hash=revsymbol(repo,str(revision)).hex()
   wr('data %d' % (len(hg_hash)))
   wr_no_nl(hg_hash)
   wr()
@@ -293,7 +400,24 @@ def export_tags(ui,repo,old_marks,mapping_cache,count,authors,tagsmap):
     count=checkpoint(count)
   return count
 
-def load_mapping(name, filename):
+def load_mapping(name, filename, mapping_is_raw):
+  raw_regexp=re.compile('^([^=]+)[ ]*=[ ]*(.+)$')
+  string_regexp='"(((\\.)|(\\")|[^"])*)"'
+  quoted_regexp=re.compile('^'+string_regexp+'[ ]*=[ ]*'+string_regexp+'$')
+
+  def parse_raw_line(line):
+    m=raw_regexp.match(line)
+    if m==None:
+      return None
+    return (m.group(1).strip(), m.group(2).strip())
+
+  def parse_quoted_line(line):
+    m=quoted_regexp.match(line)
+    if m==None:
+      return None
+    return (m.group(1).decode('string_escape'),
+            m.group(5).decode('string_escape'))
+
   cache={}
   if not os.path.exists(filename):
     sys.stderr.write('Could not open mapping file [%s]\n' % (filename))
@@ -301,18 +425,19 @@ def load_mapping(name, filename):
   f=open(filename,'r')
   l=0
   a=0
-  lre=re.compile('^([^=]+)[ ]*=[ ]*(.+)$')
   for line in f.readlines():
     l+=1
     line=line.strip()
-    if line=='' or line[0]=='#':
+    if l==1 and line[0]=='#' and line=='# quoted-escaped-strings':
       continue
-    m=lre.match(line)
+    elif line=='' or line[0]=='#':
+      continue
+    m=parse_raw_line(line) if mapping_is_raw else parse_quoted_line(line)
     if m==None:
       sys.stderr.write('Invalid file format in [%s], line %d\n' % (filename,l))
       continue
     # put key:value in cache, key without ^:
-    cache[m.group(1).strip()]=m.group(2).strip()
+    cache[m[0]]=m[1]
     a+=1
   f.close()
   sys.stderr.write('Loaded %d %s\n' % (a, name))
@@ -347,7 +472,7 @@ def verify_heads(ui,repo,cache,force,branchesmap):
 
   # verify that branch has exactly one head
   t={}
-  for h in repo.heads():
+  for h in repo.filtered('visible').heads():
     (_,_,_,_,_,_,branch,_)=get_changeset(ui,repo,h)
     if t.get(branch,False):
       sys.stderr.write('Error: repository has at least one unnamed head: hg r%s\n' %
@@ -359,7 +484,8 @@ def verify_heads(ui,repo,cache,force,branchesmap):
 
 def hg2git(repourl,m,marksfile,mappingfile,headsfile,tipfile,
            authors={},branchesmap={},tagsmap={},
-           sob=False,force=False,hgtags=False,notes=False,encoding='',fn_encoding=''):
+           sob=False,force=False,hgtags=False,notes=False,encoding='',fn_encoding='',
+           plugins={}):
   def check_cache(filename, contents):
     if len(contents) == 0:
       sys.stderr.write('Warning: %s does not contain any data, this will probably make an incremental import fail\n' % filename)
@@ -394,14 +520,28 @@ def hg2git(repourl,m,marksfile,mappingfile,headsfile,tipfile,
 
   for rev in range(0,max):
   	(revnode,_,_,_,_,_,_,_)=get_changeset(ui,repo,rev,authors)
+  	if repo[revnode].hidden():
+  		continue
   	mapping_cache[revnode.encode('hex_codec')] = str(rev)
 
+  if submodule_mappings:
+    # Make sure that all submodules are registered in the submodule-mappings file
+    for rev in range(0,max):
+      ctx=revsymbol(repo,str(rev))
+      if ctx.hidden():
+        continue
+      if ctx.substate:
+        for key in ctx.substate:
+          if key not in submodule_mappings:
+            sys.stderr.write("Error: %s not found in submodule-mappings\n" % (key))
+            return 1
 
   c=0
   brmap={}
   for rev in range(min,max):
     c=export_commit(ui,repo,rev,old_marks,max,c,authors,branchesmap,
-                    sob,brmap,hgtags,encoding,fn_encoding)
+                    sob,brmap,hgtags,encoding,fn_encoding,
+                    plugins)
   if notes:
     for rev in range(min,max):
       c=export_note(ui,repo,rev,c,authors, encoding, rev == min and min != 0)
@@ -425,6 +565,9 @@ if __name__=='__main__':
 
   parser=OptionParser()
 
+  parser.add_option("-n", "--no-auto-sanitize",action="store_false",
+      dest="auto_sanitize",default=True,
+      help="Do not perform built-in (broken in many cases) sanitizing of names")
   parser.add_option("-m","--max",type="int",dest="max",
       help="Maximum hg revision to import")
   parser.add_option("--mapping",dest="mappingfile",
@@ -459,10 +602,21 @@ if __name__=='__main__':
       help="Assume commit and author strings retrieved from Mercurial are encoded in <encoding>")
   parser.add_option("--fe",dest="fn_encoding",
       help="Assume file names from Mercurial are encoded in <filename_encoding>")
+  parser.add_option("--mappings-are-raw",dest="raw_mappings", default=False,
+      help="Assume mappings are raw <key>=<value> lines")
+  parser.add_option("--filter-contents",dest="filter_contents",
+      help="Pipe contents of each exported file through FILTER_CONTENTS <file-path> <hg-hash> <is-binary>")
+  parser.add_option("--plugin-path", type="string", dest="pluginpath",
+      help="Additional search path for plugins ")
+  parser.add_option("--plugin", action="append", type="string", dest="plugins",
+      help="Add a plugin with the given init string <name=init>")
+  parser.add_option("--subrepo-map", type="string", dest="subrepo_map",
+      help="Provide a mapping file between the subrepository name and the submodule name")
 
   (options,args)=parser.parse_args()
 
   m=-1
+  auto_sanitize = options.auto_sanitize
   if options.max!=None: m=options.max
 
   if options.marksfile==None: bail(parser,'--marks')
@@ -471,17 +625,25 @@ if __name__=='__main__':
   if options.statusfile==None: bail(parser,'--status')
   if options.repourl==None: bail(parser,'--repo')
 
+  if options.subrepo_map:
+      if not os.path.exists(options.subrepo_map):
+        sys.stderr.write('Subrepo mapping file not found %s\n'
+                         % options.subrepo_map)
+        sys.exit(1)
+      submodule_mappings=load_mapping('subrepo mappings',
+                                      options.subrepo_map,False)
+
   a={}
   if options.authorfile!=None:
-    a=load_mapping('authors', options.authorfile)
+    a=load_mapping('authors', options.authorfile, options.raw_mappings)
 
   b={}
   if options.branchesfile!=None:
-    b=load_mapping('branches', options.branchesfile)
+    b=load_mapping('branches', options.branchesfile, options.raw_mappings)
 
   t={}
   if options.tagsfile!=None:
-    t=load_mapping('tags', options.tagsfile)
+    t=load_mapping('tags', options.tagsfile, options.raw_mappings)
 
   if options.default_branch!=None:
     set_default_branch(options.default_branch)
@@ -497,8 +659,34 @@ if __name__=='__main__':
   if options.fn_encoding!=None:
     fn_encoding=options.fn_encoding
 
+  plugins=[]
+  if options.plugins!=None:
+    plugins+=options.plugins
+
+  if options.filter_contents!=None:
+    plugins+=['shell_filter_file_contents='+options.filter_contents]
+
+  plugins_dict={}
+  plugins_dict['commit_message_filters']=[]
+  plugins_dict['file_data_filters']=[]
+
+  if plugins and options.pluginpath:
+    sys.stderr.write('Using additional plugin path: ' + options.pluginpath + '\n')
+
+  for plugin in plugins:
+    split = plugin.split('=')
+    name, opts = split[0], '='.join(split[1:])
+    i = pluginloader.get_plugin(name,options.pluginpath)
+    sys.stderr.write('Loaded plugin ' + i['name'] + ' from path: ' + i['path'] +' with opts: ' + opts + '\n')
+    plugin = pluginloader.load_plugin(i).build_filter(opts)
+    if hasattr(plugin,'file_data_filter') and callable(plugin.file_data_filter):
+      plugins_dict['file_data_filters'].append(plugin.file_data_filter)
+    if hasattr(plugin, 'commit_message_filter') and callable(plugin.commit_message_filter):
+      plugins_dict['commit_message_filters'].append(plugin.commit_message_filter)
+
   sys.exit(hg2git(options.repourl,m,options.marksfile,options.mappingfile,
                   options.headsfile, options.statusfile,
                   authors=a,branchesmap=b,tagsmap=t,
                   sob=options.sob,force=options.force,hgtags=options.hgtags,
-                  notes=options.notes,encoding=encoding,fn_encoding=fn_encoding))
+                  notes=options.notes,encoding=encoding,fn_encoding=fn_encoding,
+                  plugins=plugins_dict))

hg-fast-export.sh

@@ -3,7 +3,22 @@
 # Copyright (c) 2007, 2008 Rocco Rutte <pdmef@gmx.net> and others.
 # License: MIT <http://www.opensource.org/licenses/mit-license.php>
 
-ROOT="$(dirname "$(which "$0")")"
+READLINK="readlink"
+if command -v greadlink > /dev/null; then
+  READLINK="greadlink" # Prefer greadlink over readlink
+fi
+
+if ! $READLINK -f "$(which "$0")" > /dev/null 2>&1 ; then
+    ROOT="$(dirname "$(which "$0")")"
+    if [ ! -f "$ROOT/hg-fast-export.py" ] ; then
+	echo "hg-fast-exports requires a readlink implementation which knows" \
+	     " how to canonicalize paths in order to be called via a symlink."
+	exit 1
+    fi
+else
+    ROOT="$(dirname "$($READLINK -f "$(which "$0")")")"
+fi
+
 REPO=""
 PFX="hg2git"
 SFX_MAPPING="mapping"
@@ -11,7 +26,29 @@ SFX_MARKS="marks"
 SFX_HEADS="heads"
 SFX_STATE="state"
 GFI_OPTS=""
-PYTHON=${PYTHON:-python}
+
+if [ -z "${PYTHON}" ]; then
+    # $PYTHON is not set, so we try to find a working python 2.7 to
+    # use. PEP 394 tells us to use 'python2', otherwise try plain
+    # 'python'.
+    if command -v python2 > /dev/null; then
+	PYTHON="python2"
+    elif command -v python > /dev/null; then
+	PYTHON="python"
+    else
+        echo "Could not find any python interpreter, please use the 'PYTHON'" \
+	     "environment variable to specify the interpreter to use."
+        exit 1
+    fi
+fi
+
+# Check that the python specified by the user or autodetected above is
+# >= 2.7 and < 3.
+if ! ${PYTHON} -c 'import sys; v=sys.version_info; exit(0 if v.major == 2 and v.minor >= 7 else 1)' > /dev/null 2>&1 ; then
+    echo "${PYTHON} is not a working python 2.7 interpreter, please use the" \
+	 "'PYTHON' environment variable to specify the interpreter to use."
+    exit 1
+fi
 
 USAGE="[--quiet] [-r <repo>] [--force] [-m <max>] [-s] [--hgtags] [-A <file>] [-B <file>] [-T <file>] [-M <name>] [-o <name>] [--hg-hash] [-e <encoding>]"
 LONG_USAGE="Import hg repository <repo> up to either tip or <max>
@@ -33,6 +70,8 @@ Options:
 	-B <file> Read branch map from file
 	-T <file> Read tags map from file
 	-M <name> Set the default branch name (defaults to 'master')
+	-n        Do not perform built-in (broken in many cases) sanitizing
+                  of branch/tag names.
 	-o <name> Use <name> as branch namespace to track upstream (eg 'origin')
 	--hg-hash Annotate commits with the hg hash as git notes in the
                   hg namespace.
@@ -40,6 +79,11 @@ Options:
 	              Mercurial are encoded in <encoding>
 	--fe <filename_encoding> Assume filenames from Mercurial are encoded 
 	                         in <filename_encoding>
+	--mappings-are-raw Assume mappings are raw <key>=<value> lines
+	--filter-contents <cmd>  Pipe contents of each exported file through <cmd>
+	                         with <file-path> <hg-hash> <is-binary> as arguments
+	--plugin <plugin=init>  Add a plugin with the given init string (repeatable)
+	--plugin-path <plugin-path> Add an additional plugin lookup path
 "
 case "$1" in
     -h|--help)
@@ -49,9 +93,23 @@ case "$1" in
       exit 0
 esac
 
-cd $(git rev-parse --show-toplevel) \
+IS_BARE=$(git rev-parse --is-bare-repository) \
     || (echo "Could not find git repo" ; exit 1)
-GIT_DIR=$(git rev-parse --git-dir) || exit 1
+if test "z$IS_BARE" != ztrue; then
+   # This is not a bare repo, cd to the toplevel
+   TOPLEVEL=$(git rev-parse --show-toplevel) \
+       || (echo "Could not find git repo toplevel" ; exit 1)
+   cd "$TOPLEVEL" || exit 1
+fi
+GIT_DIR=$(git rev-parse --git-dir) || (echo "Could not find git repo" ; exit 1)
+
+
+IGNORECASEWARN=""
+IGNORECASE=`git config core.ignoreCase`
+if [ "true" = "$IGNORECASE" ]; then
+    IGNORECASEWARN="true"
+fi;
+
 
 while case "$#" in 0) break ;; esac
 do
@@ -66,6 +124,7 @@ do
     --force)
       # pass --force to git-fast-import and hg-fast-export.py
       GFI_OPTS="$GFI_OPTS --force"
+      IGNORECASEWARN="";
       break
       ;;
     -*)
@@ -79,6 +138,22 @@ do
   shift
 done
 
+if [ ! -z "$IGNORECASEWARN" ]; then
+    echo "Error: The option core.ignoreCase is set to true in the git"
+    echo "repository. This will produce empty changesets for renames that just"
+    echo "change the case of the file name."
+    echo "Use --force to skip this check or change the option with"
+    echo "git config core.ignoreCase false"
+    exit 1
+fi;
+
+# Make a backup copy of each state file
+for i in $SFX_STATE $SFX_MARKS $SFX_MAPPING $SFX_HEADS ; do
+    if [ -f "$GIT_DIR/$PFX-$i" ] ; then
+	cp "$GIT_DIR/$PFX-$i" "$GIT_DIR/$PFX-$i~"
+    fi
+done
+
 # for convenience: get default repo from state file
 if [ x"$REPO" = x -a -f "$GIT_DIR/$PFX-$SFX_STATE" ] ; then
   REPO="`grep '^:repo ' "$GIT_DIR/$PFX-$SFX_STATE" | cut -d ' ' -f 2`"
@@ -106,7 +181,7 @@ $(
   exec 4>&3 3>&1 1>&4 4>&-
   {
     _e1=0
-    GIT_DIR="$GIT_DIR" $PYTHON "$ROOT/hg-fast-export.py" \
+    GIT_DIR="$GIT_DIR" "$PYTHON" "$ROOT/hg-fast-export.py" \
       --repo "$REPO" \
       --marks "$GIT_DIR/$PFX-$SFX_MARKS" \
       --mapping "$GIT_DIR/$PFX-$SFX_MAPPING" \

hg-reset.sh

@@ -24,9 +24,15 @@ Options:
 	-r	Mercurial repository to use
 "
 
-cd $(git rev-parse --show-toplevel) \
+IS_BARE=$(git rev-parse --is-bare-repository) \
     || (echo "Could not find git repo" ; exit 1)
-GIT_DIR=$(git rev-parse --git-dir) || exit 1
+if test "z$IS_BARE" != ztrue; then
+   # This is not a bare repo, cd to the toplevel
+   TOPLEVEL=$(git rev-parse --show-toplevel) \
+       || (echo "Could not find git repo toplevel" ; exit 1)
+   cd $TOPLEVEL || exit 1
+fi
+GIT_DIR=$(git rev-parse --git-dir) || (echo "Could not find git repo" ; exit 1)
 
 while case "$#" in 0) break ;; esac
 do

hg2git.py

@@ -1,9 +1,12 @@
-#!/usr/bin/env python
+#!/usr/bin/env python2
 
 # Copyright (c) 2007, 2008 Rocco Rutte <pdmef@gmx.net> and others.
 # License: MIT <http://www.opensource.org/licenses/mit-license.php>
 
 from mercurial import hg,util,ui,templatefilters
+from mercurial import error as hgerror
+from mercurial.scmutil import revsymbol,binnode
+
 import re
 import os
 import sys
@@ -32,7 +35,9 @@ def setup_repo(url):
   except TypeError:
     myui=ui.ui()
     myui.setconfig('ui', 'interactive', 'off')
-  return myui,hg.repository(myui,url)
+    # Avoids a warning when the repository has obsolete markers
+    myui.setconfig('experimental', 'evolution.createmarkers', True)
+  return myui,hg.repository(myui,url).unfiltered()
 
 def fixup_user(user,authors):
   user=user.strip("\"")
@@ -46,7 +51,7 @@ def fixup_user(user,authors):
     # and mail from hg helpers. this seems to work pretty well.
     # if email doesn't contain @, replace it with devnull@localhost
     name=templatefilters.person(user)
-    mail='<%s>' % util.email(user)
+    mail='<%s>' % templatefilters.email(user)
     if '@' not in mail:
       mail = '<devnull@localhost>'
   else:
@@ -69,7 +74,15 @@ def get_branch(name):
   return name
 
 def get_changeset(ui,repo,revision,authors={},encoding=''):
-  node=repo.lookup(revision)
+  # Starting with Mercurial 4.6 lookup no longer accepts raw hashes
+  # for lookups. Work around it by changing our behaviour depending on
+  # how it fails
+  try:
+    node=repo.lookup(revision)
+  except hgerror.ProgrammingError:
+    node=binnode(revsymbol(repo,str(revision))) # We were given a numeric rev
+  except hgerror.RepoLookupError:
+    node=revision # We got a raw hash
   (manifest,user,(time,timezone),files,desc,extra)=repo.changelog.read(node)
   if encoding:
     user=user.decode(encoding).encode('utf8')

pluginloader/__init__.py

@@ -0,0 +1,19 @@
+import os
+import imp
+PluginFolder = os.path.join(os.path.dirname(os.path.realpath(__file__)),"..","plugins")
+MainModule = "__init__"
+
+def get_plugin(name, plugin_path):
+    search_dirs = [PluginFolder]
+    if plugin_path:
+        search_dirs = [plugin_path] + search_dirs
+    for dir in search_dirs:
+        location = os.path.join(dir, name)
+        if not os.path.isdir(location) or not MainModule + ".py" in os.listdir(location):
+            continue
+        info = imp.find_module(MainModule, [location])
+        return {"name": name, "info": info, "path": location}
+    raise Exception("Could not find plugin with name " + name)
+
+def load_plugin(plugin):
+    return imp.load_module(MainModule, *plugin["info"])

plugins/branch_name_in_commit/README.md

@@ -0,0 +1,20 @@
+## Branch Name in Commit Message
+
+Mercurial has a much stronger notion of branches than Git,
+and some parties may not wish to lose the branch information
+during the migration to Git. You can use this plugin to either
+prepend or append the branch name from the mercurial
+commit into the commit message in Git.
+
+Valid arguments are:
+
+- `start`: write the branch name at the start of the commit
+- `end`: write the branch name at the end of the commit
+- `sameline`: if `start` specified, put a colon and a space
+  after the branch name, such that the commit message reads
+  `branch_name: first line of commit message`. Otherwise, the
+  branch name is on the first line of the commit message by itself.
+- `skipmaster`: Don't write the branch name if the branch is `master`.
+
+To use the plugin, add
+`--plugin branch_name_in_commit=<comma_separated_list_of_args>`.

plugins/branch_name_in_commit/__init__.py

@@ -0,0 +1,23 @@
+def build_filter(args):
+    return Filter(args)
+
+class Filter:
+    def __init__(self, args):
+        args = {arg: True for arg in args.split(',')}
+        self.start = args.pop('start', False)
+        self.end = args.pop('end', False)
+        self.sameline = args.pop('sameline', False)
+        self.skip_master = args.pop('skipmaster', False)
+
+        if self.sameline and not self.start:
+            raise ValueError("sameline option only allowed if 'start' given")
+        if args:
+            raise ValueError("Unknown args: " + ','.join(args))
+
+    def commit_message_filter(self, commit_data):
+        if not (self.skip_master and commit_data['branch'] == 'master'):
+            if self.start:
+                sep = ': ' if self.sameline else '\n' 
+                commit_data['desc'] = commit_data['branch'] + sep + commit_data['desc']
+            if self.end:
+                commit_data['desc'] = commit_data['desc'] + '\n' + commit_data['branch']

plugins/dos2unix/README.md

@@ -0,0 +1,9 @@
+## Dos2unix filter
+
+This plugin converts CRLF line ending to LF in text files in the repo.
+It is recommended that you have a .gitattributes file that maintains
+the usage of LF endings going forward, for after you have converted your
+repository.
+
+To use the plugin, add
+`--plugin dos2unix`.

plugins/dos2unix/__init__.py

@@ -0,0 +1,11 @@
+def build_filter(args):
+    return Filter(args)
+
+class Filter():
+    def __init__(self, args):
+        pass
+
+    def file_data_filter(self,file_data):
+        file_ctx = file_data['file_ctx']
+        if not file_ctx.isbinary():
+            file_data['data'] = file_data['data'].replace('\r\n', '\n')

plugins/issue_prefix/README.md

@@ -0,0 +1,19 @@
+## Issue Prefix
+
+When migrating to other source code hosting sites, there are cases where a
+project maintainer might want to reset their issue tracker and not have old
+issue numbers in commit messages referring to the wrong issue.  One way around
+this is to prefix issue numbers with some other string.
+
+If migrating to GitHub, this issue prefixing can be paired with GitHub's
+autolinking capabilitiy to link back to a different issue tracker:
+https://help.github.com/en/github/administering-a-repository/configuring-autolinks-to-reference-external-resources
+
+To use this plugin, add:
+`--plugin=issue_prefix=<some_prefix>`
+
+Example:
+`--plugin=issue_prefix=BB-`
+
+This will prefix issue numbers with the string `BB-`.  Example: `#123` will
+change to `#BB-123`.

plugins/issue_prefix/__init__.py

@@ -0,0 +1,15 @@
+# encoding=UTF-8
+"""__init__.py"""
+import re
+
+def build_filter(args):
+    return Filter(args)
+
+class Filter:
+    def __init__(self, args):
+        self.prefix = args
+
+    def commit_message_filter(self, commit_data):
+        for match in re.findall('#[1-9][0-9]+', commit_data['desc']):
+            commit_data['desc'] = commit_data['desc'].replace(
+                match, '#%s%s' % (self.prefix, match[1:]))

plugins/overwrite_null_messages/README.md

@@ -0,0 +1,23 @@
+## Overwrite Null Commit Messages
+
+There are cases (such as when creating a new, empty snippet on bitbucket
+before they deprecated mercurial repositories) where you could create a
+new repo with a single commit in it, but the message would be null.  Then,
+when attempting to convert this repository to a git repo and pushing to 
+a new host, the git push would fail with an error like this:
+
+    error: a NUL byte in commit log message not allowed
+
+To get around this, you may provide a string that will be used in place of
+a null byte in commit messages.
+
+To use the plugin, add
+
+    --plugin overwrite_null_messages=""
+
+This will use the default commit message `"<empty commit message>"`.
+
+Or to specify a different commit message, you may pass this in at the
+command line like so:
+
+    --plugin overwrite_null_messages="use this message instead"

plugins/overwrite_null_messages/__init__.py

@@ -0,0 +1,16 @@
+def build_filter(args):
+    return Filter(args)
+
+class Filter:
+    def __init__(self, args):
+        if args == '':
+            message = '<empty commit message>'
+        else:
+            message = args
+        self.message = message
+
+    def commit_message_filter(self,commit_data):
+        # Only write the commit message if the recorded commit
+        # message is null.
+        if commit_data['desc'] == '\x00':
+            commit_data['desc'] = self.message

plugins/shell_filter_file_contents/README.md

@@ -0,0 +1,30 @@
+## Shell Script File Filter
+
+This plugin uses shell scripts in order to perform filtering of files.
+If your preferred scripting is done via shell, this tool is for you.
+Be noted, though, that this method can cause an order of magnitude slow
+down. For small repositories, this wont be an issue.
+
+To use the plugin, add
+`--plugin shell_filter_file_contents=path/to/shell/script.sh`.
+The filter script is supplied to the plugin option after the plugin name,
+which is in turned passed to the plugin initialization. hg-fast-export
+runs the filter for each exported file, pipes its content to the filter's
+standard input, and uses the filter's standard output in place
+of the file's original content. An example use of this feature
+is to convert line endings in text files from CRLF to git's preferred LF,
+although this task is faster performed using the native plugin.
+
+The script is called with the following syntax:
+`FILTER_CONTENTS <file-path> <hg-hash> <is-binary>`
+
+```
+-- Start of crlf-filter.sh --
+#!/bin/sh
+# $1 = pathname of exported file relative to the root of the repo
+# $2 = Mercurial's hash of the file
+# $3 = "1" if Mercurial reports the file as binary, otherwise "0"
+
+if [ "$3" == "1" ]; then cat; else dos2unix; fi
+-- End of crlf-filter.sh --
+```

plugins/shell_filter_file_contents/__init__.py

@@ -0,0 +1,28 @@
+#Pipe contents of each exported file through FILTER_CONTENTS <file-path> <hg-hash> <is-binary>"
+import subprocess
+import shlex
+import sys
+from mercurial import node
+
+def build_filter(args):
+    return Filter(args)
+
+class Filter:
+    def __init__(self, args):
+        self.filter_contents = shlex.split(args)
+
+    def file_data_filter(self,file_data):
+        d = file_data['data']
+        file_ctx = file_data['file_ctx']
+        filename = file_data['filename']
+        filter_cmd = self.filter_contents + [filename, node.hex(file_ctx.filenode()), '1' if file_ctx.isbinary() else '0']
+        try:
+            filter_proc = subprocess.Popen(filter_cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
+            d, _ = filter_proc.communicate(d)
+        except:
+            sys.stderr.write('Running filter-contents %s:\n' % filter_cmd)
+            raise
+        filter_ret = filter_proc.poll()
+        if filter_ret:
+            raise subprocess.CalledProcessError(filter_ret, filter_cmd)
+        file_data['data'] = d