This class allows much more expressive sound synthesis:
* tremolo & vibrato
* arbitrary frequency
* different evelope & waveform per note
* all properties dynamically settable from Python code
In contrast to MidiTrack, this can be controlled from Python code,
turning notes on/off as desired.
Not tested on real HW yet, just the acceptance test based on checking
which notes it thinks are held internally.
* use a virtual fat filesystem during the test
* this makes the file I/O part more closely patch runtime which is nice
* side-steps the need to add a special function for testing
* but test still can't be run on a device, because the vfs calls
are incompatible, and you intentionally can't remount "/" anyway
* and side-steps problems with storing 'bad' toml files
This adds the __cause__, __context__ and __suppress_context__
members to exception objects and makes e.g., `raise exc from cause`
set them in the same way as standard Python.
.. it needs to operate on a FILE* rather than FIL depending on
the build.
Note that this is comparing output to expected, not to cpython dotenv
package. Because run-tests.py starts the CPython interpreter with the
'-S' (skip site initialization) flag, pip-installed packages are
not available for import inside a test file. Instead, the exp
file is generated manually:
```
circuitpython/tests$ python3 circuitpython/dotenv_test.py > circuitpython/dotenv_test.py.exp
```
Unfortunately, the test fails on test e15:
```diff
FAILURE /home/jepler/src/circuitpython/tests/results/circuitpython_dotenv_test.py
--- /home/jepler/src/circuitpython/tests/results/circuitpython_dotenv_test.py.exp 2022-10-04 09:48:16.307703128 -0500
+++ /home/jepler/src/circuitpython/tests/results/circuitpython_dotenv_test.py.out 2022-10-04 09:48:16.307703128 -0500
@@ -14,7 +14,7 @@
line
e13 e13value
e14 None
-e15 e15value
+e15 None
e16 #
e17 def
e18 #has a hash
```
