Fail with excplicit message when unable to load results file

Previously, we would simply show an empty results window. Not very
helpful.

core/app.py

@@ -148,7 +148,7 @@ class DupeGuru(Broadcaster):
         self.stats_label = StatsLabel(self)
         self.result_table = None
         self.deletion_options = DeletionOptions()
-        self.progress_window = ProgressWindow(self._job_completed)
+        self.progress_window = ProgressWindow(self._job_completed, self._job_error)
         children = [self.directory_tree, self.stats_label, self.details_panel]
         for child in children:
             child.connect()
@@ -307,6 +307,14 @@ class DupeGuru(Broadcaster):
                 }[jobid]
                 self.view.show_message(msg)
 
+    def _job_error(self, jobid, err):
+        if jobid == JobType.Load:
+            msg = tr("Could not load file: {}").format(err)
+            self.view.show_message(msg)
+            return False
+        else:
+            raise err
+
     @staticmethod
     def _remove_hardlink_dupes(files):
         seen_inodes = set()

core/results.py

@@ -222,10 +222,7 @@ class Results(Markable):
             do_match(other_files[0], other_files[1:], group)
 
         self.apply_filter(None)
-        try:
-            root = ET.parse(infile).getroot()
-        except Exception:
-            return
+        root = ET.parse(infile).getroot()
         group_elems = list(root.getiterator('group'))
         groups = []
         marked = set()

core/tests/results_test.py

@@ -9,6 +9,7 @@ import os.path as op
 
 from xml.etree import ElementTree as ET
 
+from pytest import raises
 from hscommon.testutil import eq_
 from hscommon.util import first
 
@@ -614,16 +615,15 @@ class TestCaseResultsXML:
         f.seek(0)
         app = DupeGuru()
         r = Results(app)
-        r.load_from_xml(f, None)
+        with raises(ET.ParseError):
+            r.load_from_xml(f, None)
         eq_(0, len(r.groups))
 
     def test_load_non_existant_xml(self):
         app = DupeGuru()
         r = Results(app)
-        try:
+        with raises(IOError):
             r.load_from_xml('does_not_exist.xml', None)
-        except IOError:
-            self.fail()
         eq_(0, len(r.groups))
 
     def test_remember_match_percentage(self):

hscommon

@@ -1 +1 @@
-Subproject commit 316af1bca53915f99b9bb874064cba6bee881cc1
+Subproject commit fd90d2e601752b9bf9cdd32bb6b7613fa05ec097