Fixes #767.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

* Properly render both depends and exe-depends in components. (by @ezyang)
* Import ComponentDeps qualified to avoid clashes
* Make ComponentDeps.zip compatible with containers<0.5

- New "exe-depends" field
- Dropped "depends" when it's a package; you can use
  "components" to get the information

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Actually we could probably do this a bit more properly with
UnitId in the Backpack patchset.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

This fixes #220: new-build now builds, installs and adds executables to
PATH automatically if they show up in 'build-tools'.  However, there is
still more that could be done: the new behavior only applies to a
specific list of 'build-tools' (alex, happy, etc) which Cabal recognizes
out of the box.  The plan is to introduce a new 'tool-depends' field to
allow dependencies on other executables as well.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

As requested by Duncan, the majority of fields that originally
lived in ElaboratedPackage now are moved to ElaboratedConfiguredPackage
under the prefix 'elab'.  Some code has gotten simpler as a result.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

This causes strange output when we output the install plan.
Thanks @hvr for reporting.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Two big ideas:

    * @--dependency@ takes a ComponentId, not UnitId.
      I used to think it should be a UnitId but it is
      now clear that you want to finger the indefinite
      unit id, which can be uniquely identified with
      a ComponentId

    * When hashing for an InstalledPackageId in
      new-build, we should produce a ComponentId,
      not a UnitId.

While cleaning up the results, for any codepaths which we don't plan on
implementing Backpack (Distribution.Client.Install, I'm looking at you),
just coerce ComponentId into UnitIds as necessary.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

A bit of a megapatch.  Here's what's in it:

* First, a few miscellaneous utility functions and reexports
  in Cabal.  I could have split these into a separate commit
  but I was too lazy to.

* Distribution.Client.Install got refactored:
  instead of using PackageFixedDeps, it uses IsUnit
  instead.  This is because we weren't using ComponentDeps
  in a nontrivial way; we just need some graph structure
  and IsNode (with UnitId keys) fulfills that. I also removed the
  invariant checking and error reporting because it was
  being annoying (we check the invariants already in
  SolverInstallPlan).

* Look at Distribution.Client.ProjectPlanning.Types.
  This contains the primary type change: ElaboratedConfiguredPackage
  is now EITHER a monolithic ElaboratedPackage, or a per-component
  ElaboratedComponent (it should get renamed but I didn't do that
  in this patch.)  These are what we're going to store in our
  plans: if a package we're building has a Setup script which supports
  per-component builds, we'll explode it into a component.  Otherwise
  we'll keep it as a package.  We'll see codepaths for both
  throughout.

* OK, so the expansion happens in ProjectPlanning, mostly in
  'elaborateAndExpandSolverPackage'.  You should review the
  package hash computation code closely.  When we can separate
  components, we compute a hash for each INDEPENDENTLY.  This
  is good: we get more sharing.

* We need to adjust the target resolution and pruning code
  in ProjectOrchestration and ProjectPlanning.  I did a dumb
  but easy idea: if a user mentions 'packagename' in a
  target name, I spray the PackageTarget on every
  possibly relevant IPID in buildTargets', and then pare
  it down later.

* And of course there's code in ProjectBuilding to actual
  do a configure and then build.

* We change the layout of build directories so that we can
  track each component separately.  While I was doing that,
  I also added compiler and platform information.

Custom doesn't work yet because I need to give them their own
separate component, and teach Cabal how to build them specially.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

The previous approach I took, though correct, was quite
confusing.  If I refactor InstallPlan to operate on a
per-component basis, then we'll automatically get support
for convenience libraries, which will ultimately cleaner.
(While we won't be able to get rid of support for whole
package installs, it will be safe to assume packages
using convenience libraries also support one-shot
configure.)

I didn't revert the support in cabal install; I'm not
planning on componentizing it.

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Described in: https://github.com/ghc-proposals/ghc-proposals/pull/4



./Setup configure now takes an argument to specify a specific
component name that should solely be configured.

Most of the gyrations in Configure are all about making it so that
we can feed in internal dependencies via --dependency.

I dropped the package name match sanity check to handle convenience
library package name munging.  Consider an internal library named
'q' in package 'p'.  When we install it to the package database,
we munged the package name into 'z-p-z-q', so that it doesn't
conflict with the actual package named 'q'.  Now consider when
we feed it in with --dependency q=p-0.1-hash-q.  Previously,
Cabal checked that the 'q' in --dependency matched the package
name in the database... which it doesn't. So I dropped the check.

I also had to make register/copy unconditionally install internal
libraries; otherwise you can't refer to them from later builds.

Also a miscellaneous refactor: convenience libraries are printed with a
"header" stanza now (not really a stanza header).

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Signed-off-by: Edward Z. Yang <ezyang@cs.stanford.edu>

Make annotateFailure take a maybe log file, and add a
annotateFailureNoLog for the other case. This is a little more future
proof and simplifies things at the call sites.

Reporting build logs is important as we otherwise have no real info for
why deps failed to build. It does make the presentation more difficult
however because build logs can be long and in principle there can be
several, which means it can take up more than a single screen in a
console. The first thing users notice is typically the last few
messages, so in the case that we're presenting long build logs then its
important to also include a short summary at the end.

So our approach is this: for packages where we want to show a build log,
we dump those first, in full, each with a header to indicate which
package it is, log file name (for later reference), plus any extra
detail we have from the phase of the failure or the exception. Then
after all build logs we end with a short summary of the failure(s). For
packages where we do not show a build log (e.g. local packages that dump
live to the console) we only present a summary at the end, but we
include a little more detail than for the packages that had a build log
since this is the only thing we report for them. So we include details
of the exception.

The PlanningFailed case does not happen. The ReplFailed, HaddocksFailed
cases were previously covered by BuildFailed but they're worth
disinguishing.

In both cases it's optional and only added when the log file is used.
This will be used later in reporting the build outcomes.

We're going to alter and extend the BuildResult and BuildFailure types
for the new-build code, so we cannot share those types with the old
install code.

This patch doesn't change the structure, just redefines them locally and
switches uses to record style so we can add new fields easily.

I think these names are now a bit more induitive / less confusing and a
bit more consistent.

We now have BuildOutcome(s) to mean either failure or a build result,
and BuildResult to mean the result of a non-failing build.

[ci skip]