feat: add scan --replace to take over tags removed in other apps

tests/test_cmd.py

@@ -57,3 +57,10 @@ def test_purge_keeps_config(otag, tmp_path):
     otag('p')
     assert not (tmp_path / orvani.CONTEXT_FILE).exists()
     assert (tmp_path / orvani.CONFIG_FILE).exists()
+
+
+def test_scan_replace(otag, tmp_path):
+    (tmp_path / 'a.py').write_text('# otag: #one\n')
+    (tmp_path / orvani.CONTEXT_FILE).write_text('a.py --- #one #gone\n')
+    otag('s', '--replace')
+    assert (tmp_path / orvani.CONTEXT_FILE).read_text() == 'a.py --- #one\n'

tests/test_frontmatter.py

@@ -71,3 +71,13 @@ def test_rst_is_not_handled(cwd):
     with pytest.raises(UnsupportedType):
         o.write_metadata('doc.rst', 'frontmatter')
     assert (cwd / 'doc.rst').read_text() == 'Title\n=====\n'
+
+
+def test_scan_replace_drops_tags_the_file_no_longer_has(cwd):
+    (cwd / 'a.md').write_text('---\ntags: [one]\n---\n')
+    (cwd / 'b.md').write_text('no front matter\n')
+    (cwd / orvani.CONTEXT_FILE).write_text('a.md --- #one #gone\nb.md --- #kept\n')
+    OrvaniTag().scan('.', False)
+    assert (cwd / orvani.CONTEXT_FILE).read_text() == 'a.md --- #one #gone\nb.md --- #kept\n'
+    OrvaniTag().scan('.', False, replace=True)
+    assert (cwd / orvani.CONTEXT_FILE).read_text() == 'a.md --- #one\nb.md --- #kept\n'