I recently answered a questionanswered a question that did not include a main method or any tests. The code provided was a just a handful of methods. Without any obvious way to drive the code, I had to guess at how each method would be used and how it should operate.
In my particular case, the question centered around porting code from one language to another, and the original implementation included documentation and tests for each method. However, these tests were not trivially runnable as I would have needed to rewrite them in the new language.
Should we expect people asking for review to provide a way to run the code, just as we expect a description of what the code does? Should the way to exercise the code be provided in the same language as the code under review?