avoid name clash in cargo crates downloaded from git repositories

Crates referenced by their git revision have a version but might have
different revisions.
The source filename ignored the revision such that sources from
different revisions were considered the same file which either fails the
checksum verification or the build.
Append the revision if specified to disambiguate them.

easybuild/easyblocks/generic/cargo.py

@@ -81,12 +81,15 @@ def extra_options(extra_vars=None):
         return extra_vars
 
     @staticmethod
-    def crate_src_filename(pkg_name, pkg_version, *args):
-        """Crate tarball filename based on package name and version"""
-        return "{0}-{1}.tar.gz".format(pkg_name, pkg_version)
+    def crate_src_filename(pkg_name, pkg_version, _=None, rev=None):
+        """Crate tarball filename based on package name, version and optionally git revision"""
+        parts = [pkg_name, pkg_version]
+        if rev is not None:
+            parts.append(rev)
+        return '-'.join(parts) + ".tar.gz"
 
     @staticmethod
-    def crate_download_filename(pkg_name, pkg_version, *args):
+    def crate_download_filename(pkg_name, pkg_version):
         """Crate download filename based on package name and version"""
         return "{0}/{1}/download".format(pkg_name, pkg_version)
 
@@ -148,7 +151,7 @@ def __init__(self, *args, **kwargs):
                     repo_name = repo_name[:-4]
                 sources.append({
                     'git_config': {'url': url, 'repo_name': repo_name, 'commit': rev},
-                    'filename': self.crate_src_filename(crate, version),
+                    'filename': self.crate_src_filename(crate, version, rev=rev),
                 })
 
         # copy EasyConfig instance before we make changes to it