Ed Morley eb6ee49dfe Emit metrics for how the Python version was chosen (#1069) ...

Currently an app's Python version can be set via a few different means:
- explicitly by the user (via `runtime.txt` or `Pipfile.lock`)
- implicitly via the sticky versions feature (for existing apps)
- implicitly via default version for new apps / those with empty cache

In order to determine the priority of features like automatic Python
patch version upgrades for sticky-versioned apps, it's useful to have
metrics for these.

There were previously no tests for either the sticky versions feature,
or changing the Python version by updating the `runtime.txt` file, so
I've added some now (given that I updated the conditional to add the
metrics, so useful to have coverage).

I've also removed the confusing overwrite of `DEFAULT_PYTHON_VERSION`
with the cached version, and kept them as two separate variables.

Closes @W-8099632@.
Closes @W-8099645@.

2020-09-18 18:48:57 +01:00

..

fixtures

Emit metrics for how the Python version was chosen (#1069)

2020-09-18 18:48:57 +01:00

run-deps

Tests: Run detect/compile/release in a clean environment (#1016)

2020-07-24 18:10:11 +01:00

run-features

Update pip to 20.1.1 (#1030)

2020-08-03 19:45:41 +01:00

run-versions

Emit metrics for how the Python version was chosen (#1069)

2020-09-18 18:48:57 +01:00

shunit2

Fix some Bash issues (#491)

2017-12-15 09:19:03 -05:00

utils

Tests: Delete redundant detect(), compile() and release() (#1017)

2020-07-24 18:19:01 +01:00