[formatter] add 'i' and 'f' conversions (#6582)

https://github.com/mikf/gallery-dl/issues/6582#issuecomment-2792166608

docs/formatting.md

@@ -176,6 +176,18 @@ Conversion specifiers allow to *convert* the value to a different form or type.
     <td></td>
     <td></td>
 </tr>
+<tr>
+    <td align="center"><code>i</code></td>
+    <td>Convert value to <a href="https://docs.python.org/3/library/functions.html#int"><code>int</code></a></td>
+    <td></td>
+    <td></td>
+</tr>
+<tr>
+    <td align="center"><code>f</code></td>
+    <td>Convert value to <a href="https://docs.python.org/3/library/functions.html#float"><code>float</code></a></td>
+    <td></td>
+    <td></td>
+</tr>
 </tbody>
 </table>
 
@@ -233,7 +245,7 @@ Format specifiers can be used for advanced formatting by using the options provi
     <td><code>Foo&nbsp;Bar</code></td>
 </tr>
 <tr>
-    <td><code>{foo:L6/&nbsp;.../}</code></td>
+    <td><code>{foo:X6/&nbsp;.../}</code></td>
     <td><code>Fo&nbsp;...</code></td>
 </tr>
 <tr>

gallery_dl/formatter.py

@@ -495,6 +495,8 @@ _CONVERSIONS = {
     "s": str,
     "r": repr,
     "a": ascii,
+    "i": int,
+    "f": float,
 }
 _FORMAT_SPECIFIERS = {
     "?": _parse_optional,

test/test_formatter.py

@@ -35,6 +35,8 @@ class TestFormatter(unittest.TestCase):
         "ds": "2010-01-01T01:00:00+0100",
         "dt": datetime.datetime(2010, 1, 1),
         "dt_dst": datetime.datetime(2010, 6, 1),
+        "i_str": "12345",
+        "f_str": "12.45",
         "name": "Name",
         "title1": "Title",
         "title2": "",
@@ -70,6 +72,9 @@ class TestFormatter(unittest.TestCase):
         self._run_test("{a!L}", 11)
         self._run_test("{l!L}", 3)
         self._run_test("{d!L}", 3)
+        self._run_test("{i_str!i}", 12345)
+        self._run_test("{i_str!f}", 12345.0)
+        self._run_test("{f_str!f}", 12.45)
 
         with self.assertRaises(KeyError):
             self._run_test("{a!q}", "hello world")
@@ -483,10 +488,10 @@ def noarg():
             fmt4 = formatter.parse("\fM " + path + ":lengths")
 
         self.assertEqual(fmt1.format_map(self.kwdict), "'Title' by Name")
-        self.assertEqual(fmt2.format_map(self.kwdict), "126")
+        self.assertEqual(fmt2.format_map(self.kwdict), "136")
 
         self.assertEqual(fmt3.format_map(self.kwdict), "'Title' by Name")
-        self.assertEqual(fmt4.format_map(self.kwdict), "126")
+        self.assertEqual(fmt4.format_map(self.kwdict), "136")
 
         with self.assertRaises(TypeError):
             self.assertEqual(fmt0.format_map(self.kwdict), "")