From 3a2d670aedee44e692132a11e19a69d05555bb49 Mon Sep 17 00:00:00 2001
From: Sam Clegg <sbc@chromium.org>
Date: Wed, 15 Jan 2025 09:34:32 -0800
Subject: [PATCH] Update min python version from 3.6 to 3.8

The reason for picking 3.8 here is that it provides all the features
we currently have need of, and it available in the places we care about:

- debian/stable (bookworm): 3.11
- ubuntu/LTS (focal): 3.8
- emsdk: 3.9.2

Replaces: #23378
Fixes: #23387
---
 ChangeLog.md         |  2 ++
 tools/building.py    | 13 +------------
 tools/shared.py      |  6 +++---
 tools/system_libs.py | 11 +----------
 4 files changed, 7 insertions(+), 25 deletions(-)

diff --git a/ChangeLog.md b/ChangeLog.md
index b8b984af170e5..5e29d7cea758b 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -30,6 +30,8 @@ See docs/process.md for more on how version tagging works.
   a conflict between the `majorVersion` requested and the WebGL support defined
   via linker flags (`MIN_WEBGL_VERSION` and `MAX_WEBGL_VERSION`). This warning
   will be turned into a hard failure in a future release. (#23372, #23416)
+- The version of python required to run emscripten was bumped from 3.6 to 3.8.
+  (#23417)
 
 4.0.0 - 01/14/25
 ----------------
diff --git a/tools/building.py b/tools/building.py
index 3d764fe82d33a..231b810ce4c60 100644
--- a/tools/building.py
+++ b/tools/building.py
@@ -476,17 +476,6 @@ def check_closure_compiler(cmd, args, env, allowed_to_fail):
   return True
 
 
-# Remove this once we require python3.7 and can use std.isascii.
-# See: https://docs.python.org/3/library/stdtypes.html#str.isascii
-def isascii(s):
-  try:
-    s.encode('ascii')
-  except UnicodeEncodeError:
-    return False
-  else:
-    return True
-
-
 def get_closure_compiler_and_env(user_args):
   env = shared.env_with_node_in_path()
   closure_cmd = get_closure_compiler()
@@ -623,7 +612,7 @@ def run_closure_cmd(cmd, filename, env):
   tempfiles = shared.get_temp_files()
 
   def move_to_safe_7bit_ascii_filename(filename):
-    if isascii(filename):
+    if filename.isascii():
       return os.path.abspath(filename)
     safe_filename = tempfiles.get('.js').name  # Safe 7-bit filename
     shutil.copyfile(filename, safe_filename)
diff --git a/tools/shared.py b/tools/shared.py
index 1f4f37f24b5b0..d41af7466ba24 100644
--- a/tools/shared.py
+++ b/tools/shared.py
@@ -20,9 +20,9 @@
 import sys
 import tempfile
 
-# We depend on python 3.6 for fstring support
-if sys.version_info < (3, 6):
-  print('error: emscripten requires python 3.6 or above', file=sys.stderr)
+# We depend on python 3.8 features
+if sys.version_info < (3, 8):
+  print(f'error: emscripten requires python 3.8 or above ({sys.executable} {sys.version})', file=sys.stderr)
   sys.exit(1)
 
 from . import colored_logger
diff --git a/tools/system_libs.py b/tools/system_libs.py
index d2b390d3ee925..31f31924110a7 100644
--- a/tools/system_libs.py
+++ b/tools/system_libs.py
@@ -2435,17 +2435,8 @@ def calculate(args):
   return ret
 
 
-# Once we require python 3.8 we can use shutil.copytree with
-# dirs_exist_ok=True and remove this function.
 def copytree_exist_ok(src, dst):
-  os.makedirs(dst, exist_ok=True)
-  for entry in os.scandir(src):
-    srcname = os.path.join(src, entry.name)
-    dstname = os.path.join(dst, entry.name)
-    if entry.is_dir():
-      copytree_exist_ok(srcname, dstname)
-    else:
-      shared.safe_copy(srcname, dstname)
+  shutil.copytree(src, dst, dirs_exist_ok=True)
 
 
 def install_system_headers(stamp):