bitbake: fetch2/git: Allow git fetcher to support subdir param

The git fetcher is odd in that it supports destsuffix as a parameter but not
the default documented subdir parameter. destsuffix is more limited as it can't
take absolute paths. Rework the code to correctly support subdir.

Also cleanup to use the None default .get() values and be a bit more pythonic
and use subpath as the variable name for subpath for code clarity.

We could consider dropping destsuffix as a parameter as some future point.

Also fix the tests not to pass in a subdir parameter which was never used
but now causes errors.

(Bitbake rev: 66953f06fe822e4001efabd9fc1c985ea2b03f96)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/fetch2/git.py

@@ -516,13 +516,24 @@ class Git(FetchMethod):
     def unpack(self, ud, destdir, d):
         """ unpack the downloaded src to destdir"""
 
-        subdir = ud.parm.get("subpath", "")
-        if subdir != "":
-            readpathspec = ":%s" % subdir
-            def_destsuffix = "%s/" % os.path.basename(subdir.rstrip('/'))
-        else:
-            readpathspec = ""
-            def_destsuffix = "git/"
+        subdir = ud.parm.get("subdir")
+        subpath = ud.parm.get("subpath")
+        readpathspec = ""
+        def_destsuffix = "git/"
+
+        if subpath:
+            readpathspec = ":%s" % subpath
+            def_destsuffix = "%s/" % os.path.basename(subpath.rstrip('/'))
+
+        if subdir:
+            # If 'subdir' param exists, create a dir and use it as destination for unpack cmd
+            if os.path.isabs(subdir):
+                if not os.path.realpath(subdir).startswith(os.path.realpath(destdir)):
+                    raise bb.fetch2.UnpackError("subdir argument isn't a subdirectory of unpack root %s" % destdir, ud.url)
+                destdir = subdir
+            else:
+                destdir = os.path.join(destdir, subdir)
+            def_destsuffix = ""
 
         destsuffix = ud.parm.get("destsuffix", def_destsuffix)
         destdir = ud.destdir = os.path.join(destdir, destsuffix)
@@ -569,7 +580,7 @@ class Git(FetchMethod):
                 bb.note("Repository %s has LFS content but it is not being fetched" % (repourl))
 
         if not ud.nocheckout:
-            if subdir != "":
+            if subpath:
                 runfetchcmd("%s read-tree %s%s" % (ud.basecmd, ud.revisions[ud.names[0]], readpathspec), d,
                             workdir=destdir)
                 runfetchcmd("%s checkout-index -q -f -a" % ud.basecmd, d, workdir=destdir)

bitbake/lib/bb/tests/fetch.py

@@ -2157,7 +2157,7 @@ class GitLfsTest(FetcherTest):
     def test_lfs_enabled(self):
         import shutil
 
-        uri = 'git://%s;protocol=file;subdir=${S};lfs=1' % self.srcdir
+        uri = 'git://%s;protocol=file;lfs=1' % self.srcdir
         self.d.setVar('SRC_URI', uri)
 
         # Careful: suppress initial attempt at downloading until
@@ -2182,7 +2182,7 @@ class GitLfsTest(FetcherTest):
     def test_lfs_disabled(self):
         import shutil
 
-        uri = 'git://%s;protocol=file;subdir=${S};lfs=0' % self.srcdir
+        uri = 'git://%s;protocol=file;lfs=0' % self.srcdir
         self.d.setVar('SRC_URI', uri)
 
         # In contrast to test_lfs_enabled(), allow the implicit download