Add support for Python 3.14.6 and 3.13.14 (#2105)

Release announcement:
https://blog.python.org/2026/06/python-3146-31314/

Changelogs:
https://docs.python.org/release/3.14.6/whatsnew/changelog.html#python-3-14-6-final
https://docs.python.org/release/3.13.14/whatsnew/changelog.html#python-3-13-14-final

Binary builds:
https://github.com/heroku/heroku-buildpack-python/actions/runs/27281631125
https://github.com/heroku/heroku-buildpack-python/actions/runs/27289906221

GUS-W-20590506.
GUS-W-20590551.

Author: edmorley

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## [Unreleased]
 
+- The Python 3.14 version alias now resolves to Python 3.14.6. ([#2105](https://github.com/heroku/heroku-buildpack-python/pull/2105))
+- The Python 3.13 version alias now resolves to Python 3.13.14. ([#2105](https://github.com/heroku/heroku-buildpack-python/pull/2105))
 
 ## [v345] - 2026-06-04
 

lib/python_version.sh

@@ -7,8 +7,8 @@ set -euo pipefail
 LATEST_PYTHON_3_10="3.10.20"
 LATEST_PYTHON_3_11="3.11.15"
 LATEST_PYTHON_3_12="3.12.13"
-LATEST_PYTHON_3_13="3.13.13"
-LATEST_PYTHON_3_14="3.14.5"
+LATEST_PYTHON_3_13="3.13.14"
+LATEST_PYTHON_3_14="3.14.6"
 
 OLDEST_SUPPORTED_PYTHON_3_MINOR_VERSION=10
 NEWEST_SUPPORTED_PYTHON_3_MINOR_VERSION=14

spec/hatchet/python_version_spec.rb

@@ -88,19 +88,15 @@
       end
     end
 
-    # TODO: Enable on Heroku-26 after the default Python version next changes (for the 3.14.5
-    # release), since for now there isn't a historic buildpack version we can use in this test
-    # whose stack check permits Heroku-26 and also has a different default Python version so
-    # that we can test the sticky versions feature.
-    context 'with an app last built using an older default Python version', stacks: %w[heroku-22 heroku-24] do
+    context 'with an app last built using an older default Python version' do
       # This test performs an initial build using an older buildpack version, followed
       # by a build using the current version. This ensures that:
       # - The current buildpack can successfully read the version metadata
       #   written to the build cache by older buildpack versions.
       # - If no Python version is specified, the same major version as the
       #   last build is used (sticky major versioning).
       # - Changes in the pip version are handled correctly.
-      let(:buildpacks) { ['https://github.com/heroku/heroku-buildpack-python#v267'] }
+      let(:buildpacks) { ['https://github.com/heroku/heroku-buildpack-python#v342'] }
 
       it 'builds with the same major Python version as the last build' do
         app.deploy do |app|
@@ -109,7 +105,7 @@
           app.push!
           expect(clean_output(app.output)).to include(<<~OUTPUT)
             remote: -----> Python app detected
-            remote: -----> No Python version was specified. Using the same major version as the last build: Python 3.12
+            remote: -----> No Python version was specified. Using the same major version as the last build: Python 3.14
             remote: 
             remote:  !     Warning: No Python version was specified.
             remote:  !     
@@ -131,9 +127,9 @@
             remote:  !     In the new file, specify your app's major Python version number
             remote:  !     only. Don't include quotes or a 'python-' prefix.
             remote:  !     
-            remote:  !     For example, to request the latest version of Python 3.12,
+            remote:  !     For example, to request the latest version of Python 3.14,
             remote:  !     update your .python-version file so it contains exactly:
-            remote:  !     3.12
+            remote:  !     3.14
             remote:  !     
             remote:  !     We strongly recommend that you don't specify the Python patch
             remote:  !     version number, since it will pin your app to an exact Python
@@ -152,13 +148,12 @@
             remote:  !     file and this warning will be made an error.
             remote: 
             remote: -----> Discarding cache since:
-            remote:        - The Python version has changed from 3.12.7 to #{LATEST_PYTHON_3_12}
-            remote:        - The pip version has changed from 24.0 to #{PIP_VERSION}
-            remote:        - The legacy SQLite3 headers and CLI binary need to be uninstalled
-            remote: -----> Installing Python #{LATEST_PYTHON_3_12}
-            remote: -----> Installing pip #{PIP_VERSION} and setuptools #{SETUPTOOLS_VERSION}
+            remote:        - The Python version has changed from 3.14.4 to #{LATEST_PYTHON_3_14}
+            remote:        - The pip version has changed from 26.0.1 to #{PIP_VERSION}
+            remote: -----> Installing Python #{LATEST_PYTHON_3_14}
+            remote: -----> Installing pip #{PIP_VERSION}
           OUTPUT
-          expect(app.run('python -V')).to eq("Python #{LATEST_PYTHON_3_12}\n")
+          expect(app.run('python -V')).to eq("Python #{LATEST_PYTHON_3_14}\n")
           expect($CHILD_STATUS.exitstatus).to eq(0)
         end
       end

spec/spec_helper.rb

@@ -13,8 +13,8 @@
 LATEST_PYTHON_3_10 = '3.10.20'
 LATEST_PYTHON_3_11 = '3.11.15'
 LATEST_PYTHON_3_12 = '3.12.13'
-LATEST_PYTHON_3_13 = '3.13.13'
-LATEST_PYTHON_3_14 = '3.14.5'
+LATEST_PYTHON_3_13 = '3.13.14'
+LATEST_PYTHON_3_14 = '3.14.6'
 DEFAULT_PYTHON_FULL_VERSION = LATEST_PYTHON_3_14
 DEFAULT_PYTHON_MAJOR_VERSION = DEFAULT_PYTHON_FULL_VERSION.gsub(/\.\d+$/, '')