patman: Update to use absolute imports

Use absolute imports in patman so that installing patman is easier and it
can run with its modules being in the 'patman' subdirectory.

Rename patman.py since Python does not like the Python module name being
the same as the module directory.

Add the required path to sys.path() so that running patman locally works.

Change-Id: Ia00f61964f3e38a72f4eef24878c0756cda8bf9e
Signed-off-by: Simon Glass <sjg@chromium.org>
BUG=chromium:1048179
TEST=sudo emerge patman
Then run 'patman'
(tests do not pass as they need quite a bit more work for portage)
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/u-boot/+/2037907
Reviewed-by: Mike Frysinger <vapier@chromium.org>
diff --git a/tools/patman/checkpatch.py b/tools/patman/checkpatch.py
index d47ea43..795b519 100644
--- a/tools/patman/checkpatch.py
+++ b/tools/patman/checkpatch.py
@@ -3,12 +3,14 @@
 #
 
 import collections
-import command
-import gitutil
 import os
 import re
 import sys
-import terminal
+
+from patman import command
+from patman import gitutil
+from patman import terminal
+from patman import tools
 
 def FindCheckPatch():
     top_level = gitutil.GetTopLevel()
diff --git a/tools/patman/command.py b/tools/patman/command.py
index 5fbd2c4..e67ac15 100644
--- a/tools/patman/command.py
+++ b/tools/patman/command.py
@@ -3,8 +3,9 @@
 #
 
 import os
-import cros_subprocess
-import tools
+
+from patman import cros_subprocess
+from patman import tools
 
 """Shell command ease-ups for Python."""
 
diff --git a/tools/patman/func_test.py b/tools/patman/func_test.py
index 76319ff..b8dee18 100644
--- a/tools/patman/func_test.py
+++ b/tools/patman/func_test.py
@@ -17,10 +17,10 @@
 except ImportError:
     from io import StringIO
 
-import gitutil
-import patchstream
-import settings
-import tools
+from patman import gitutil
+from patman import patchstream
+from patman import settings
+from patman import tools
 
 
 @contextlib.contextmanager
diff --git a/tools/patman/get_maintainer.py b/tools/patman/get_maintainer.py
index 0ffb55a..473f0fe 100644
--- a/tools/patman/get_maintainer.py
+++ b/tools/patman/get_maintainer.py
@@ -2,10 +2,11 @@
 # Copyright (c) 2012 The Chromium OS Authors.
 #
 
-import command
-import gitutil
 import os
 
+from patman import command
+from patman import gitutil
+
 def FindGetMaintainer():
     """Look for the get_maintainer.pl script.
 
diff --git a/tools/patman/gitutil.py b/tools/patman/gitutil.py
index a2a225c..770a051 100644
--- a/tools/patman/gitutil.py
+++ b/tools/patman/gitutil.py
@@ -2,17 +2,17 @@
 # Copyright (c) 2011 The Chromium OS Authors.
 #
 
-import command
 import re
 import os
-import series
 import subprocess
 import sys
-import terminal
 
-import checkpatch
-import settings
-import tools
+from patman import checkpatch
+from patman import command
+from patman import series
+from patman import settings
+from patman import terminal
+from patman import tools
 
 # True to use --no-decorate - we check this in Setup()
 use_no_decorate = True
diff --git a/tools/patman/patman.py b/tools/patman/main.py
similarity index 93%
rename from tools/patman/patman.py
rename to tools/patman/main.py
index cf53e53..8cce567 100755
--- a/tools/patman/patman.py
+++ b/tools/patman/main.py
@@ -12,19 +12,20 @@
 import sys
 import unittest
 
+if __name__ == "__main__":
+    # Allow 'from patman import xxx to work'
+    our_path = os.path.dirname(os.path.realpath(__file__))
+    sys.path.append(os.path.join(our_path, '..'))
+
 # Our modules
-try:
-    from patman import checkpatch, command, gitutil, patchstream, \
-        project, settings, terminal, test
-except ImportError:
-    import checkpatch
-    import command
-    import gitutil
-    import patchstream
-    import project
-    import settings
-    import terminal
-    import test
+from patman import checkpatch
+from patman import command
+from patman import gitutil
+from patman import patchstream
+from patman import project
+from patman import settings
+from patman import terminal
+from patman import test
 
 
 parser = OptionParser()
@@ -85,7 +86,7 @@
 # Run our meagre tests
 elif options.test:
     import doctest
-    import func_test
+    from patman import func_test
 
     sys.argv = [sys.argv[0]]
     result = unittest.TestResult()
diff --git a/tools/patman/patchstream.py b/tools/patman/patchstream.py
index df3eb74..4052975 100644
--- a/tools/patman/patchstream.py
+++ b/tools/patman/patchstream.py
@@ -9,10 +9,10 @@
 import shutil
 import tempfile
 
-import command
-import commit
-import gitutil
-from series import Series
+from patman import command
+from patman import commit
+from patman import gitutil
+from patman.series import Series
 
 # Tags that we detect and remove
 re_remove = re.compile('^BUG=|^TEST=|^BRANCH=|^Review URL:'
diff --git a/tools/patman/patman b/tools/patman/patman
index 6cc3d7a..11a5d8e 120000
--- a/tools/patman/patman
+++ b/tools/patman/patman
@@ -1 +1 @@
-patman.py
\ No newline at end of file
+main.py
\ No newline at end of file
diff --git a/tools/patman/project.py b/tools/patman/project.py
index 1d9cfc0..2dfc303 100644
--- a/tools/patman/project.py
+++ b/tools/patman/project.py
@@ -4,7 +4,7 @@
 
 import os.path
 
-import gitutil
+from patman import gitutil
 
 def DetectProject():
     """Autodetect the name of the current project.
diff --git a/tools/patman/series.py b/tools/patman/series.py
index a15f762..9baf5ce 100644
--- a/tools/patman/series.py
+++ b/tools/patman/series.py
@@ -7,11 +7,11 @@
 import itertools
 import os
 
-import get_maintainer
-import gitutil
-import settings
-import terminal
-import tools
+from patman import get_maintainer
+from patman import gitutil
+from patman import settings
+from patman import terminal
+from patman import tools
 
 # Series-xxx tags that we understand
 valid_series = ['to', 'cc', 'version', 'changes', 'prefix', 'notes', 'name',
diff --git a/tools/patman/settings.py b/tools/patman/settings.py
index 5dc83a8..8acfb92 100644
--- a/tools/patman/settings.py
+++ b/tools/patman/settings.py
@@ -12,9 +12,9 @@
 import os
 import re
 
-import command
-import gitutil
-import tools
+from patman import command
+from patman import gitutil
+from patman import tools
 
 """Default settings per-project.
 
diff --git a/tools/patman/test.py b/tools/patman/test.py
index 889e186..e7f709e 100644
--- a/tools/patman/test.py
+++ b/tools/patman/test.py
@@ -8,11 +8,11 @@
 import tempfile
 import unittest
 
-import checkpatch
-import gitutil
-import patchstream
-import series
-import commit
+from patman import checkpatch
+from patman import gitutil
+from patman import patchstream
+from patman import series
+from patman import commit
 
 
 class TestPatch(unittest.TestCase):
diff --git a/tools/patman/tools.py b/tools/patman/tools.py
index 3feddb2..7b0840d 100644
--- a/tools/patman/tools.py
+++ b/tools/patman/tools.py
@@ -5,7 +5,6 @@
 
 from __future__ import print_function
 
-import command
 import glob
 import os
 import shutil
@@ -13,7 +12,8 @@
 import sys
 import tempfile
 
-import tout
+from patman import command
+from patman import tout
 
 # Output directly (generally this is temporary)
 outdir = None
diff --git a/tools/patman/tout.py b/tools/patman/tout.py
index 2a38485..834d4f4 100644
--- a/tools/patman/tout.py
+++ b/tools/patman/tout.py
@@ -8,7 +8,7 @@
 
 import sys
 
-import terminal
+from patman import terminal
 
 # Output verbosity levels that we support
 ERROR, WARNING, NOTICE, INFO, DETAIL, DEBUG = range(6)