Commit Graph

9 Commits

Author SHA1 Message Date
Alisdair McDiarmid d7ef123c12 refactoring: Move nested modules
When applying module `moved` statements by iterating through modules in
state, we previously required an exact match from the `moved`
statement's `from` field and the module address. This permitted moving
resources directly inside a module, but did not recur into module calls
within those moved modules.

This commit moves that exact match requirement so that it only applies
to `moved` statements targeting resources. In turn this allows nested
modules to be moved.
2021-12-21 16:25:06 -05:00
James Bardin cac1f5c264 refactoring: exhaustive NestedWithin checks
When checking dependencies between statements, we need to check all
combinations of To and From addresses.
2021-09-27 12:48:17 -04:00
Martin Atkins 83f0376673 refactoring: ApplyMoves new return type
When we originally stubbed ApplyMoves we didn't know yet how exactly we'd
be using the result, so we made it a double-indexed map allowing looking
up moves in both directions.

However, in practice we only actually need to look up old addresses by new
addresses, and so this commit first removes the double indexing so that
each move is only represented by one element in the map.

We also need to describe situations where a move was blocked, because in
a future commit we'll generate some warnings in those cases. Therefore
ApplyMoves now returns a MoveResults object which contains both a map of
changes and a map of blocks. The map of blocks isn't used yet as of this
commit, but we'll use it in a later commit to produce warnings within
the "terraform" package.
2021-09-22 09:01:10 -07:00
Martin Atkins ee9e346039 refactoring: ApplyMoves skips moving when destination address occupied
Per our rule that the content of the state can never make a move statement
invalid, our behavior for two objects trying to occupy the same address
will be to just ignore that and let the object already at the address
take priority.

For the moment this is silent from an end-user perspective and appears
only in our internal logs. However, I'm hoping that our future planned
adjustment to the interface of this function will include some way to
allow reporting these collisions in some end-user-visible way, either as
a separate warning per collision or as a single warning that collects
together all of the collisions into a single message somehow.

This situation can arise both because the previous run state already
contained an object at the target address of a move and because more than
one move ends up trying to target the same location. In the latter case,
which one "wins" is decided by our depth-first traversal order, which is
in turn derived from our chaining and nesting rules and is therefore
arbitrary but deterministic.
2021-09-20 09:06:22 -07:00
James Bardin 30afb492ab fix ApplyMove test with nested modules working
The addrs package can now correctly handle the combinations of nested
module endpoints, which fixes these 2 tests.
2021-08-20 15:17:06 -04:00
James Bardin 553d6525d2 more move tests 2021-08-19 12:05:53 -04:00
James Bardin 789317dc05 additional test 2021-08-10 10:11:57 -04:00
James Bardin 09ab952683 fix ApplyMoves tests
Add empty result value, since ApplyMoves does not return nil.
Fix the desired addresses for moves.
2021-08-02 17:23:35 -04:00
Martin Atkins 3e5bfa7364 refactoring: Stubbing of the logic for handling moves
This is a whole lot of nothing right now, just stubbing out some control
flow that ultimately just leads to TODOs that cause it to do nothing at
all.

My intent here is to get this cross-cutting skeleton in place and thus
make it easier for us to collaborate on adding the meat to it, so that
it's more likely we can work on different parts separately and still get
a result that tessellates.
2021-07-14 17:37:48 -07:00