[core] Raise minimum recommended Python version to 3.8 (#8183)

Authored by: Grub4K

devscripts/changelog_override.json

@@ -88,5 +88,10 @@
         "when": "59e92b1f1833440bb2190f847eb735cf0f90bc85",
         "short": "[rh:urllib] Simplify gzip decoding (#7611)",
         "authors": ["Grub4K"]
+    },
+    {
+        "action": "add",
+        "when": "c1d71d0d9f41db5e4306c86af232f5f6220a130b",
+        "short": "[priority] **The minimum *recommended* Python version has been raised to 3.8**\nSince Python 3.7 has reached end-of-life, support for it will be dropped soon. [Read more](https://github.com/yt-dlp/yt-dlp/issues/7803)"
     }
 ]

test/test_execution.py

@@ -45,6 +45,9 @@ def test_lazy_extractors(self):
             self.assertTrue(os.path.exists(LAZY_EXTRACTORS))
 
             _, stderr = self.run_yt_dlp(opts=('-s', 'test:'))
+            # `MIN_RECOMMENDED` emits a deprecated feature warning for deprecated python versions
+            if stderr and stderr.startswith('Deprecated Feature: Support for Python'):
+                stderr = ''
             self.assertFalse(stderr)
 
             subprocess.check_call([sys.executable, 'test/test_all_urls.py'], cwd=rootDir, stdout=subprocess.DEVNULL)

yt_dlp/YoutubeDL.py

@@ -60,7 +60,7 @@
     get_postprocessor,
 )
 from .postprocessor.ffmpeg import resolve_mapping as resolve_recode_mapping
-from .update import REPOSITORY, current_git_head, detect_variant
+from .update import REPOSITORY, _get_system_deprecation, current_git_head, detect_variant
 from .utils import (
     DEFAULT_OUTTMPL,
     IDENTITY,
@@ -640,17 +640,9 @@ def process_color_policy(stream):
             for name, stream in self._out_files.items_ if name != 'console'
         })
 
-        # The code is left like this to be reused for future deprecations
-        MIN_SUPPORTED, MIN_RECOMMENDED = (3, 7), (3, 7)
-        current_version = sys.version_info[:2]
-        if current_version < MIN_RECOMMENDED:
-            msg = ('Support for Python version %d.%d has been deprecated. '
-                   'See  https://github.com/yt-dlp/yt-dlp/issues/3764  for more details.'
-                   '\n                    You will no longer receive updates on this version')
-            if current_version < MIN_SUPPORTED:
-                msg = 'Python version %d.%d is no longer supported'
-            self.deprecated_feature(
-                f'{msg}! Please update to Python %d.%d or above' % (*current_version, *MIN_RECOMMENDED))
+        system_deprecation = _get_system_deprecation()
+        if system_deprecation:
+            self.deprecated_feature(system_deprecation.replace('\n', '\n                    '))
 
         if self.params.get('allow_unplayable_formats'):
             self.report_warning(

yt_dlp/update.py

@@ -112,6 +112,31 @@ def is_non_updateable():
         detect_variant(), _NON_UPDATEABLE_REASONS['unknown' if VARIANT else 'other'])
 
 
+def _get_system_deprecation():
+    MIN_SUPPORTED, MIN_RECOMMENDED = (3, 7), (3, 8)
+
+    if sys.version_info > MIN_RECOMMENDED:
+        return None
+
+    major, minor = sys.version_info[:2]
+    if sys.version_info < MIN_SUPPORTED:
+        msg = f'Python version {major}.{minor} is no longer supported'
+    else:
+        msg = f'Support for Python version {major}.{minor} has been deprecated. '
+        # Temporary until `win_x86_exe` uses 3.8, which will deprecate Vista and Server 2008
+        if detect_variant() == 'win_x86_exe':
+            platform_name = platform.platform()
+            if any(platform_name.startswith(f'Windows-{name}') for name in ('Vista', '2008Server')):
+                msg = 'Support for Windows Vista/Server 2008 has been deprecated. '
+            else:
+                return None
+        msg += ('See  https://github.com/yt-dlp/yt-dlp/issues/7803  for details.'
+                '\nYou may stop receiving updates on this version at any time')
+
+    major, minor = MIN_RECOMMENDED
+    return f'{msg}! Please update to Python {major}.{minor} or above'
+
+
 def _sha256_file(path):
     h = hashlib.sha256()
     mv = memoryview(bytearray(128 * 1024))