Allow more than one version of the same software

In SlapOS we do in fact support/allow different versions for different
dependencies, so there isn't a reason why this should be disallowed.

----

kirr: added TODO regarding general multiversion support.

See merge-request for more context and discussion.

/reviewed-on nexedi/nxd-bom!3
/reviewed-by @jerome, @luke, @kirr

nxdbom/__init__.py

@@ -83,7 +83,7 @@ def bom_software(installed_software_path): # -> {} (name,kind) -> PkgInfo
 
 
         info = PkgInfo(name, ver, kind, url)
-        bkey = (name, kind)
+        bkey = (name, kind, ver)
         if bkey in bom:
             assert bom[bkey] == info,  (bom[bkey], info)
         else:
@@ -371,6 +371,7 @@ def namever(url, failonerr=True): # -> (name, ver)  | None if !failonerr
     # XXX hack: ERP5 SR uses both readline8 and readline-5
     # XXX       Cloudooo SR ----//---- libpng16 and libpng12
     # XXX       Cloudooo SR ----//---- python2 and python3
+    # TODO -> general multiversion support
     if name == 'readline' and ver.startswith('5'):    name += '5'
     if name == 'libpng'   and ver.startswith('1.2'):  name += '12'
     if name == 'Python'   and ver.startswith('3'):    name += '3'

nxdbom/nxdbom_test.py

@@ -456,6 +456,20 @@ url = http://snowball.tartarus.org/dist/libstemmer_c.tgz
 libstemmer_c                            http://snowball.tartarus.org/dist/libstemmer_c.tgz
 """)
 
+# two different versions of the same software are ok
+case1("""\
+[scons-0]
+recipe = slapos.recipe.build:download-unpacked
+url = https://prdownloads.sourceforge.net/scons/scons-local-2.3.0.tar.gz
+
+[scons-1]
+recipe = slapos.recipe.build:download-unpacked
+url = https://prdownloads.sourceforge.net/scons/scons-local-2.3.1.tar.gz
+""", """\
+scons-local                  2.3.0      https://prdownloads.sourceforge.net/scons/scons-local-2.3.0.tar.gz
+scons-local                  2.3.1      https://prdownloads.sourceforge.net/scons/scons-local-2.3.1.tar.gz
+""")
+
 
 @pytest.mark.parametrize('build,bomok', testv)
 def test_bom_software(tmpdir, build, bomok):