diffs: fixed outdated files in pull-requests re-using the filediff raw_id for anchor generation.

In some cases when there are no longer any files this caused error since filediff wasn't present.
In addition this generated wrong ids since it used a last-defined attribute on a for loop.

Fixes  #5567

rhodecode/api/tests/test_get_repo_changeset.py

@@ -54,7 +54,7 b' class TestGetRepoChangeset(object):'
             details=details,
         )
         response = api_call(self.app, params)
-        expected = 'commit_id must be a string value'
+        expected = "commit_id must be a string value got <type 'int'> instead"
         assert_error(id_, expected, given=response.body)
 
     @pytest.mark.parametrize("details", ['basic', 'extended', 'full'])
@@ -137,5 +137,5 b' class TestGetRepoChangeset(object):'
             details=details,
         )
         response = api_call(self.app, params)
-        expected = 'commit_id must be a string value'
+        expected = "commit_id must be a string value got <type 'int'> instead"
         assert_error(id_, expected, given=response.body)

rhodecode/lib/vcs/backends/base.py

@@ -735,7 +735,7 b' class BaseRepository(object):'
 
     def _validate_commit_id(self, commit_id):
         if not isinstance(commit_id, compat.string_types):
-            raise TypeError("commit_id must be a string value")
+            raise TypeError("commit_id must be a string value got {} instead".format(type(commit_id)))
 
     def _validate_commit_idx(self, commit_idx):
         if not isinstance(commit_idx, (int, long)):

rhodecode/templates/codeblocks/diffs.mako

@@ -367,15 +367,17 b" return '%s_%s_%i' % (h.md5_safe(commit+f"
 
     ## outdated comments that are made for a file that has been deleted
     % for filename, comments_dict in (deleted_files_comments or {}).items():
+
         <%
             display_state = 'display: none'
             open_comments_in_file = [x for x in comments_dict['comments'] if x.outdated is False]
             if open_comments_in_file:
                 display_state = ''
+            fid = str(id(filename))
         %>
         <div class="filediffs filediff-outdated" style="${display_state}">
             <input ${(collapse_all and 'checked' or '')} class="filediff-collapse-state collapse-${diffset_container_id}" id="filediff-collapse-${id(filename)}" type="checkbox" onchange="updateSticky();">
-            <div class="filediff" data-f-path="${filename}"  id="a_${h.FID(filediff.raw_id, filename)}">
+            <div class="filediff" data-f-path="${filename}"  id="a_${h.FID(fid, filename)}">
                 <label for="filediff-collapse-${id(filename)}" class="filediff-heading">
                     <div class="filediff-collapse-indicator icon-"></div>
 
@@ -387,7 +389,7 b" return '%s_%s_%i' % (h.md5_safe(commit+f"
                         ## file op, doesn't need translation
                         <span class="pill" op="removed">removed in this version</span>
                     </span>
-                    <a class="pill filediff-anchor" href="#a_${h.FID(filediff.raw_id, filename)}">¶</a>
+                    <a class="pill filediff-anchor" href="#a_${h.FID(fid, filename)}">¶</a>
                     <span class="pill-group pull-right">
                         <span class="pill" op="deleted">-${comments_dict['stats']}</span>
                     </span>