Fixes#323
Let's now all go an a little rant about spaghetti code...
The result of this code is that the missing paths are not printed
anymore. The basic issue was that the parent class of this command is
StorePathsCommand, which inherits from BuiltPathsCommand, and their
purpose is to work on path that are clearly in the store, building them
if needed (and ofc telling the user about what's missing), the sequance
of calls is:
- BuiltPathsCommand::run(ref<Store> store, Installables && installables)
- Installable::toBuiltPaths( *getEvaluator()->begin(aio()),
getEvalStore(), store, realiseMode, operateOn, installables);
where operateOn is Output by default, realiseMode is Derivation, so
the only thing that can be built are the derivations for the required
installables
- Installable::build(state, evalStore, store, mode, installables)
- Installable::build2(state, evalStore, store, mode, installables,
bMode)
And that final call has the following:
```
switch (mode) {
case Realise::Nothing:
case Realise::Derivation:
state.aio.blockOn(printMissing(store, pathsToBuild, lvlError));
```
So there were two options, hack a new spaghetti in the existing
spaghetti code, or condense all those calls that are actually useless in
our case because they mostly transform a list of installables into a map
from installables to their BuiltPath which are then iterated to retrieve
the final outputs, whereas it is possible to directly get the required
paths in a much more efficient manner and without printing unrequired
stuff through a multitude of intertwined function calls by simply
replacing one method that was previously inherited from the grandparent
class
Change-Id: I1d2baaef5a099cd98b63b5346f2613914c6cd2ac
Tom Hubrecht
7d764670c8