Pushy lacks a simple remote "exec" method

[Andrew Wilkins]

Currently to execute a non-trivial piece of code you must compile a code object and evaluate it, e.g.:-
    conn = pushy.connect(...)
    code_obj = conn.eval("compile")(source, "<filename>", "exec")
    conn.eval(code_obj, locals=..., globals=...)

This should be made simpler, by introducing a function that wraps these steps.

[Andrew Wilkins (axwalk)]

I will add two new methods to pushy.client.Client: execute, and compile.

The execute method will simply be a shortcut for eval(compile(source)). e.g.:-
    conn.execute("print 123")
= conn.eval(conn.compile("print 123"))

The compile method will do two things:
 - Compile source code to a remote code object, which can be used with the remote eval builtin.
 - If given a locally defined function. will get its source (via inspect.getsource), define it in the remote interpreter, and return the function to the caller.

e.g.
    >>> print conn.compile("print 123")
    >>> <code object <module> at 0x94101d0, file "<pushy>", line 1>

e.g. (Non-interactive; inspect.getsource only works for functions defined in files.)
    def sleep(sec):
        import time
        time.sleep(sec)
    remote_sleep = conn.compile(sleep)
    remote_sleep(0.5)

[Andrew Wilkins (axwalk)]

An option for compiling dynamically defined functions (e.g. in an interactive session) is to manually create a "code" object in the remote interpreter, and wrap it in a types.FunctionType. I have tested this and it works. The caveat would be that the remote Python interpreter would have to support the byte code emitted by the local one, since it would/could not be recompiled from source.

[Andrew Wilkins (axwalk)]

Done. I have added "execute" and "compile" methods as described above. The compile method will attempt first to use inspect.getsource, and, failing that, will clone the code/function object in the remote interpreter.