Fix case-insensitive XML media type formatting

CHANGELOG.md

@@ -3,6 +3,10 @@
 This document records all notable changes to [HTTPie](https://httpie.io).
 This project adheres to [Semantic Versioning](https://semver.org/).
 
+## Unreleased
+
+- Format XML responses with uppercase or mixed-case media types.
+
 ## [3.2.4](https://github.com/httpie/cli/compare/3.2.3...3.2.4) (2024-11-01)
 
 - Fix default certs loading and unpin `requests`. ([#1596](https://github.com/httpie/cli/issues/1596))

docs/README.md

@@ -1892,7 +1892,7 @@ Formatting has the following effects:
 - HTTP headers are sorted by name.
 - JSON data is indented, sorted by keys, and unicode escapes are converted
   to the characters they represent.
-- XML and XHTML data is indented.
+- XML and XHTML data is indented. XML media types are matched case-insensitively.
 
 Please note that sometimes there might be changes made by formatters on the actual response body (e.g.,
 collapsing empty tags on XML) but the end result will always be semantically indistinguishable. Some of

httpie/output/formatters/xml.py

@@ -57,7 +57,7 @@ def __init__(self, **kwargs):
         self.enabled = self.format_options['xml']['format']
 
     def format_body(self, body: str, mime: str):
-        if 'xml' not in mime:
+        if 'xml' not in mime.lower():
             return body
 
         from xml.parsers.expat import ExpatError

tests/test_xml.py

@@ -97,3 +97,20 @@ def test_invalid_xml(file):
     # No formatting done, data is simply printed as-is.
     r = http(DUMMY_URL)
     assert xml_data in r
+
+
+@pytest.mark.parametrize('content_type', [
+    'APPLICATION/XML',
+    'Application/Atom+XML; charset=utf-8',
+])
+@responses.activate
+def test_xml_media_type_is_case_insensitive(content_type):
+    responses.add(
+        responses.GET,
+        DUMMY_URL,
+        body=XML_DATA_RAW,
+        content_type=content_type,
+    )
+
+    r = http('--pretty=format', '--body', DUMMY_URL)
+    assert XML_DATA_FORMATTED in r