Tests: Misc package manager test improvements (heroku#1738)

Backports some test naming/strategy improvements from the
CNB, along with some general classic-specific clean-ups.

Towards heroku#1616.
GUS-W-17679633.

Author: edmorley

spec/fixtures/ci_requirements/.python-version spec/fixtures/ci_pip/.python-version

@@ -4,9 +4,3 @@ verify_ssl = true
 name = "pypi"
 
 [packages]
-urllib3 = "*"
-
-[dev-packages]
-
-[requires]
-python_version = "3.13"

spec/fixtures/ci_requirements/app.json spec/fixtures/ci_pip/app.json

@@ -0,0 +1,2 @@
+# This shouldn't be installed, since requirements-test.txt should only be used on Heroku CI.
+pytest

spec/fixtures/ci_requirements/bin/compile spec/fixtures/ci_pip/bin/compile

@@ -0,0 +1,2 @@
+# This tests that the setup.py fallback is not used when other package manager files exist.
+raise RuntimeError("setup.py should not be run!")

spec/fixtures/ci_requirements/bin/detect spec/fixtures/ci_pip/bin/detect

@@ -0,0 +1,2 @@
+# A quick to install package that relies on the Python headers from the base image.
+git+https://github.com/pypa/[email protected]#egg=extension.dist&subdirectory=tests/testdata/extension.dist

spec/fixtures/ci_requirements/bin/post_compile spec/fixtures/ci_pip/bin/post_compile

@@ -0,0 +1 @@
+pysqlite3

spec/fixtures/ci_requirements/bin/print-env-vars.sh spec/fixtures/ci_pip/bin/print-env-vars.sh

@@ -1,9 +1,2 @@
-# This file is here to confirm we don't try and create the fallback requirements
-# file containing '-e .' when using Pipenv.
-
-from setuptools import setup
-
-setup(
-  name='test',
-  install_requires=['six'],
-)
+# This tests that the setup.py fallback is not used when other package manager files exist.
+raise RuntimeError("setup.py should not be run!")

spec/fixtures/ci_requirements/requirements-test.txt spec/fixtures/ci_pip/requirements-test.txt

@@ -0,0 +1,2 @@
+# This tests that the setup.py fallback is not used when other package manager files exist.
+raise RuntimeError("setup.py should not be run!")

spec/fixtures/ci_requirements/requirements.txt spec/fixtures/ci_pip/requirements.txt

@@ -6,7 +6,7 @@
   let(:buildpacks) { [:default, 'heroku-community/inline'] }
 
   context 'when using pip' do
-    let(:app) { Hatchet::Runner.new('spec/fixtures/ci_requirements', buildpacks:) }
+    let(:app) { Hatchet::Runner.new('spec/fixtures/ci_pip', buildpacks:) }
 
     it 'installs both normal and test dependencies and uses cache on subsequent runs' do
       app.run_ci do |test_run|

spec/fixtures/requirements_django_latest/requirements.txt spec/fixtures/django_latest/requirements.txt

@@ -32,7 +32,7 @@
     end
 
     context 'when Django is installed but manage.py does not exist' do
-      let(:app) { Hatchet::Runner.new('spec/fixtures/requirements_django_latest') }
+      let(:app) { Hatchet::Runner.new('spec/fixtures/django_latest') }
 
       it 'skips collectstatic' do
         app.deploy do |app|
@@ -44,7 +44,7 @@
 
     context 'when DISABLE_COLLECTSTATIC=1' do
       let(:app) do
-        Hatchet::Runner.new('spec/fixtures/requirements_django_latest', config: { 'DISABLE_COLLECTSTATIC' => '1' })
+        Hatchet::Runner.new('spec/fixtures/django_latest', config: { 'DISABLE_COLLECTSTATIC' => '1' })
       end
 
       it 'skips collectstatic' do

spec/fixtures/requirements_basic/.python-version spec/fixtures/multiple_package_managers/.python-version

@@ -46,4 +46,96 @@
       end
     end
   end
+
+  # TODO: Deprecate/sunset the setup.py file fallback.
+  context 'when there is only a setup.py' do
+    let(:app) { Hatchet::Runner.new('spec/fixtures/setup_py_only') }
+
+    it 'installs packages from setup.py using pip' do
+      app.deploy do |app|
+        expect(clean_output(app.output)).to match(Regexp.new(<<~REGEX, Regexp::MULTILINE))
+          remote: -----> Python app detected
+          remote: -----> Using Python #{DEFAULT_PYTHON_MAJOR_VERSION} specified in .python-version
+          remote: -----> Installing Python #{DEFAULT_PYTHON_FULL_VERSION}
+          remote: -----> Installing pip #{PIP_VERSION}
+          remote: -----> Installing dependencies using 'pip install --editable .'
+          remote:        Obtaining file:///tmp/build_.*
+          remote:        .+
+          remote:        Installing collected packages: six, test
+          remote:        Successfully installed six-.+ test-0.0.0
+        REGEX
+      end
+    end
+  end
+
+  # This case will be turned into an error in the future.
+  context 'when there are multiple package manager files' do
+    let(:app) { Hatchet::Runner.new('spec/fixtures/multiple_package_managers') }
+
+    it 'outputs a warning and builds with the first listed' do
+      app.deploy do |app|
+        expect(clean_output(app.output)).to match(Regexp.new(<<~REGEX))
+          remote: -----> Python app detected
+          remote: 
+          remote:  !     Warning: Multiple Python package manager files were found.
+          remote:  !     
+          remote:  !     Exactly one package manager file should be present in your app's
+          remote:  !     source code, however, several were found:
+          remote:  !     
+          remote:  !     Pipfile.lock \\(Pipenv\\)
+          remote:  !     requirements.txt \\(pip\\)
+          remote:  !     poetry.lock \\(Poetry\\)
+          remote:  !     
+          remote:  !     For now, we will build your app using the first package manager
+          remote:  !     listed above, however, in the future this warning will become
+          remote:  !     an error.
+          remote:  !     
+          remote:  !     Decide which package manager you want to use with your app, and
+          remote:  !     then delete the file\\(s\\) and any config from the others.
+          remote: 
+          remote: 
+          remote:  !     Note: We recently added support for the package manager Poetry.
+          remote:  !     If you are using a third-party Poetry buildpack you must remove
+          remote:  !     it, otherwise the requirements.txt file it generates will cause
+          remote:  !     the warning above.
+          remote: 
+          remote: -----> Using Python #{DEFAULT_PYTHON_MAJOR_VERSION} specified in .python-version
+          remote: -----> Installing Python #{DEFAULT_PYTHON_FULL_VERSION}
+          remote: -----> Installing pip #{PIP_VERSION}
+          remote: -----> Installing Pipenv #{PIPENV_VERSION}
+          remote: -----> Installing dependencies using 'pipenv install --deploy'
+          remote:        Installing dependencies from Pipfile.lock \\(.+\\)...
+        REGEX
+      end
+    end
+  end
+
+  context 'when the package manager has changed since the last build' do
+    let(:app) { Hatchet::Runner.new('spec/fixtures/pip_basic') }
+
+    it 'clears the cache before installing with the new package manager' do
+      app.deploy do |app|
+        FileUtils.rm('requirements.txt')
+        FileUtils.cp(FIXTURE_DIR.join('poetry_basic/pyproject.toml'), '.')
+        FileUtils.cp(FIXTURE_DIR.join('poetry_basic/poetry.lock'), '.')
+        app.commit!
+        app.push!
+        expect(clean_output(app.output)).to include(<<~OUTPUT)
+          remote: -----> Python app detected
+          remote: -----> Using Python #{DEFAULT_PYTHON_MAJOR_VERSION} specified in .python-version
+          remote: -----> Discarding cache since:
+          remote:        - The package manager has changed from pip to poetry
+          remote: -----> Installing Python #{DEFAULT_PYTHON_FULL_VERSION}
+          remote: -----> Installing Poetry #{POETRY_VERSION}
+          remote: -----> Installing dependencies using 'poetry sync --only main'
+          remote:        Installing dependencies from lock file
+          remote:        
+          remote:        Package operations: 1 install, 0 updates, 0 removals
+          remote:        
+          remote:          - Installing typing-extensions (4.12.2)
+          remote: -----> Discovering process types
+        OUTPUT
+      end
+    end
+  end
 end