bitbake: svn.py: Stop SVN from directly pulling from an external layer w/o fetcher

Add a new option to the svn fetcher url "externals=allowed".  This will allow
a user to enable svn co w/ externals.  However, this does avoid the fetcher,
network access and mirror systems.

By default we no longer allow externals in the checkout.  This ensures a
deterministic download.  The system does attempt to identify SVN repos that
have externals enabled, and will warn the user.  It is up to the user to
determine if these are necessary for the recipe.  They may disable the warning
by adding "externals=nowarn" to the url.

In the future we would like to parse this list and see if the items are already
in the SRC_URI for that recipe, but with SVN being in limited use these days
that extra work is likely not worth the trouble.

Add test cases that generated a local SVN tree, with an external source
set to github bitbake in svn format.  One test case checks that externals are
ignored, and one checks that they in downloaded.

(Bitbake rev: bf53f07c3647e57d8452a7743a2b04bcb72c80d6)

Signed-off-by: Mark Hatle <mark.hatle@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/fetch2/svn.py

@@ -91,6 +91,13 @@ class Svn(FetchMethod):
             svncmd = "%s log --limit 1 %s %s://%s/%s/" % (ud.basecmd, " ".join(options), proto, svnroot, ud.module)
         else:
             suffix = ""
+
+            # externals may be either 'allowed' or 'nowarn', but not both.  Allowed
+            # will not issue a warning, but will log to the debug buffer what has likely
+            # been downloaded by SVN.
+            if not ("externals" in ud.parm and ud.parm["externals"] == "allowed"):
+                options.append("--ignore-externals")
+
             if ud.revision:
                 options.append("-r %s" % ud.revision)
                 suffix = "@%s" % (ud.revision)
@@ -136,6 +143,18 @@ class Svn(FetchMethod):
                 bb.fetch2.check_network_access(d, svnfetchcmd, ud.url)
                 runfetchcmd(svnfetchcmd, d, workdir=ud.pkgdir)
 
+            if not ("externals" in ud.parm and ud.parm["externals"] == "nowarn"):
+                # Warn the user if this had externals (won't catch them all)
+                output = runfetchcmd("svn propget svn:externals", d, workdir=ud.moddir)
+                if output:
+                    if "--ignore-externals" in svnfetchcmd.split():
+                        bb.warn("%s contains svn:externals." % ud.url)
+                        bb.warn("These should be added to the recipe SRC_URI as necessary.")
+                        bb.warn("svn fetch has ignored externals:\n%s" % output)
+                        bb.warn("To disable this warning add ';externals=nowarn' to the url.")
+                    else:
+                        bb.debug(1, "svn repository has externals:\n%s" % output)
+
             scmdata = ud.parm.get("scmdata", "")
             if scmdata == "keep":
                 tar_flags = ""