optimism 2.6.6

Very simple testing framework suitable for beginner programmers, with easy functions for accomplishing most common testing tasks like providing input. Use with Python >=3.9 for best results, but it should be compatible with Python >=3.6.

optimism

A very small & simple unit-testing framework designed to provide all the basic necessities to beginner programmers as simply as possible.

Designed by Peter Mawhorter.

Dependencies

Works on Python versions 3.8 and up, with 3.9+ recommended.

Installing

To install from PyPI, run the following command on the command-line:

python3 -m pip install optimism

Once it's installed, you can run the tests using:

pytest optimism.py
pytest test_examples.py

Usage

Use the testCase function to establish an expression as a test case. Then use the expectResult, expectOutputContains, and/or expectCustom functions to establish expectations for that test. Use provideInput and/or captureOutput and related functions to deal with input/output testing. Use runFile to create a test for an entire file.

See the documentation for more details on how to use it and what each function does.

Changelog

• Version 2.0 creates a less fragile test-case API while streamlining the expectations API to focus on values only. expect now takes an expression and expected value together as two arguments, and testCase isn't needed. expectType was also added to encourage thinking about types. These functions are now intended to be used for debugging rather than testing. There are new testFunction, testFile, and testBlock functions which create TestManager objects that have a case method to derive TestCase objects. Those objects have checkResult and checkOutputLines methods, as well as provideInputs. Now that we're in control of running tests, the old input/output capturing/mocking functions are mostly removed (they were quite confusing to students). The new test case API does require the use of methods, but as a result it can avoid the following: 1. The use of tuples to specify arguments 2. The specification of arguments where one argument is an extra argument to specify the test case 3. The use of behind-the-scenes magic to remember the current test case (students were confused and it encourages bad mental models). 4. The use of triple-quoted strings for specifying input or output (too hard to get newlines right at the start and end).
• Version 2.2.0 changes some method names in the new API to make them more explicit: checkResult becomes checkReturnValue, and checkOutputLines becomes checkPrintedLines.
• Version 2.5.0 adds automatic skipping of checks for a case after one check fails, and includes a global setting to apply this at the manager level or disable it.
• Version 2.5.1 fixes a bug with comparisons on recursive structures.
• Version 2.6.0 upgrades checkCustom to include a 'case' key in the dictionary supplied to the checker whose value is the TestCase object that checkCustom was called on. This allows custom checkers to do things like access the arguments given to a FunctionCase.
• Version 2.6.1 Upgrades checkCustom again; it now accepts additional arguments to be passed on to the custom checker, which vastly improves usability!
• Version 2.6.2 Fixes a bug in the comparison code that would cause crashes when comparing dictionaries with different key sets. It also adds unit tests for the compare function.
• Version 2.6.3 introduces the checkFileContainsLines method, and also standardizes the difference-finding code and merges it with equality-checking code, removing checkEquality and introducing findFirstDifference instead (compare) remains but just calls findFirstDifference internally. Also fixes a bug w/ printing tracebacks for come checkers (need to standardize that!). Also adds global skip-on-failure and sets that as the default!
• Version 2.6.4 immediately changes checkFileContainsLines to checkFileLines to avoid confusion about whether we're checking against the whole file (we are).
• Version 2.6.5 fixes a bug with displaying filenames when a file does not exist and checkFileLines is used, and also sets the default length higher for printing first differing lines in findFirstDifference since those lines are displayed on their own line anyways. Fixes a bug where list differences were not displayed correctly, and improves the usefulness of first differences displayed for dictionaries w/ different lengths. Also fixes a bug where strings which were equivalent modulo trailing whitespace would not be treated as equivalent.
• Version 2.6.6 changes from splitlines to split('\n') in a few places because the latter is more robust to extra carriage returns. This changes how some error messages look and it means that in some places the newline at the end of a file actually counts as having a blank line there in terms of output (behavior is mostly unchanged). Also escaped carriage returns in displayed strings so they're more visible. From this version we do NOT support files that use just '\r' as a newline as easily. But IGNORE_TRAILING_WHITESPACE will properly get rid of any extra '\r' before a newline, so when that's on (the default) this shouldn't change much. A test of this behavior was added to the file test example.