This is a proper replacement for the previous shell-based placeholder hack.
Here is a summary:
- `clerk runtest` (normally run by ninja) is much extended:
* besides generating the test@out file, it checks individual tests for success
and can write a report file containing their status, and the positions for
their (expected/current) outputs (this uses `Marshal`)
* it now handles out-tests directly in addition to inline-tests, for which
it generates the separate output file ; they are included in the report
- ninja is now tasked with building all the test reports (which shouldn't fail);
for directories, individual reports are concatenated (as before).
Removing intermediate report rules, and out-test rules means that the ninja
file is much simplified.
- then, clerk takes back control, reads the final reports and formats them in a
user-friendly way. Printing the reports may imply running `diff` internally.
In particular, the commands to easily reproduce each test are provided.
Resetting the test results if required is also done directly by clerk, at this
stage.
A few switches are available to customise the output, but I am waiting for some
feedback before deciding what to make available from the CLI.
The `clerk report` command is available to manually explore test reports, but
normally the processing is done directly at the end of `clerk test` (i.e. ninja
will no longer call that command)
- Clearly distinguish Exceptions from Errors. The only catchable exception
available in our AST is `EmptyError`, so the corresponding nodes are made less
generic, and a node `FatalError` is added
- Runtime errors are defined as a specific type in the OCaml runtime, with a
carrier exception and printing functions. These are used throughout, and
consistently by the interpreter. They always carry a position, that can be
converted to be printed with the fancy compiler location printer, or in a
simpler way from the backends.
- All operators that might be subject to an error take a position as argument,
in order to print an informative message without relying on backtraces from
the backend
