Before, results from `dca` would look something like
## + py/meta/alerts/remote-flow-sources-reach
- django/django@c2250cf_cb8f: tests/messages_tests/urls.py:38:16:38:48
reachable with taint-tracking from RemoteFlowSource
- django/django@c2250cf_cb8f: tests/messages_tests/urls.py:38:9:38:12
reachable with taint-tracking from RemoteFlowSource
now it should make it easier to spot _what_ it is that actually changed,
since we pretty-print the node.
I debated whether to add a
`MISSING: use=moduleImport("builtins").getMember("print").getReturn()`
annotation to the last line.
Ultimately, I decided to add it, as we likely _do_ want this information
to propagate into inner functions (even if the value of `var2` may
change before `func4` is called).
Unsurprisingly, the only thing affected by this was the `import-helper`
tests. These have lost all of the results relating to `ImportMember`s,
but apart from that the underlying behaviour should be the same.
I also limited the test to only `CfgNode`s, as a bunch of `EssaNode`s
suddenly appeared when I switched to API graphs.
Finally, I used `API::moduleImport` with a dotted name in the type
tracking tests. This goes against the API graphs interface, but I think
it's more correct for this use case, as these type trackers are doing
the "module attribute lookup" bit manually.
Moves the current test out of `test.py`, as otherwise any unknown global
(like, say, `sink`) would _also_ be considered to be something
potentially defined in `unknown`.
Splits `ModuleVariableNode` away from `LocalSourceNode`, instead
creating a class `TypeTrackingNode` that encapsulates both of these.
This means we no longer have module variable nodes as part of
`LocalSourceNode` (which is good, since they have no "local" aspect to
them), and hence we can have `LocalSourceNode` inherit directly from
`ExprNode` (which makes the API a bit nicer).
Unfortunately these are breaking changes, so we can't actually fulfil
the above two desiderata until the `track` and `backtrack` methods on
`LocalSourceNode` have been fully deprecated. For this reason, we
preserve the present implementation of `LocalSourceNode`, and instead
lay the foundation for switching over in the future, by deprecating
`track` and `backtrack` on `LocalSourceNode`.
