Implement 'Attempt to fill hole' code action (#431)

* [WIP] Start work on 'auto'

* Get current binding

* Fix currentBindingName for class methods

* Proper impl of getDefiningBindings

* Forgot to checkin bindsites

* [WIP] Update version of refinery

* Bind all tyvars if possible

* WIP: Instantiate polymorphic functions

* Split out fresh type variables when instantiating

* Make everything compile

* Separate out tactics

* oneWayUnifyRule

* [WIP] Add 'TacticState'

* [WIP] Tweak 'unify' and 'unifyOneWayRule'

* [WIP] Start work on skolem tracking

* [WIP] Fix 'checkSkolemUnification'

* Update judgement type

* Add a Context to TacticM

* Don't destruct already destructed

* Remove the internal lib

* Cleanup warnings

* Move debug machinery into *.Debug

* Rip types out of machinery

* Cleanup warnings

* Continue splitting Machinery

* Rip out GHC and Naming

* Get it all compiling

* Stop re-exporting from Machinery

* Split out codegen/rules

* Remove gross/unused tactics

* Make newSubgoal derive from an existing judgement

* remove newJudgement

* Disallow current function from auto

* Cleanup auto

* Stop using the Judgement ctor

* Track pattern value

* Better showAstData

* Get module-scoped funcs

* Split all data constructors

* assumption -> assume

* Don't destruct if there are zero datacons

* Lambda case destruct tactics

* Fix the tests

* Rip out debug stuff since it fails CI

* Tests for lambda case actions

* Golden testing machinery

* Attempt to fill hole

* [WIP] Use 'refinery-0.2.0.0'

* [WIP] Update refinery in all stack.yaml files

* Bump version in cabal file

* Bump cabal index state

* Sort goals by heuristic

* Naming for unit types

* Heuristic for auto

* Penalize holes more

* Naming for unit types

* Give the name "unit" to units

* Fallback names for symbols and punctuation

* Get "good" name for symbolic names

* Update plugins/tactics/src/Ide/Plugin/Tactic/CodeGen.hs

Co-authored-by: wz1000 <zubin@cmi.ac.in>

* Make the TacticState strict

* Make the judgement strict

* Simplify when we use position mapping

* Move bindsites to ghcide

Co-authored-by: Sandy Maguire <sandy@sandymaguire.me>
Co-authored-by: wz1000 <zubin@cmi.ac.in>

Author: 3 people

cabal.project

@@ -20,6 +20,6 @@ package ghcide
 
 write-ghc-environment-files: never
 
-index-state: 2020-09-23T17:24:43Z
+index-state: 2020-09-30T21:52:43Z
 
 allow-newer: data-tree-print:base

ghcide

@@ -80,7 +80,7 @@ library
 executable haskell-language-server
   import:           agpl, common-deps
   main-is:          Main.hs
-  hs-source-dirs:   exe plugins/default/src
+  hs-source-dirs:   exe plugins/default/src plugins/tactics/src
   other-modules:
     Ide.Plugin.Eval
     Ide.Plugin.Example
@@ -93,9 +93,17 @@ executable haskell-language-server
     Ide.Plugin.Retrie
     Ide.Plugin.StylishHaskell
     Ide.Plugin.Tactic
-    Ide.Plugin.Tactic.Types
+    Ide.Plugin.Tactic.CodeGen
+    Ide.Plugin.Tactic.Context
+    Ide.Plugin.Tactic.Debug
+    Ide.Plugin.Tactic.GHC
+    Ide.Plugin.Tactic.Judgements
     Ide.Plugin.Tactic.Machinery
+    Ide.Plugin.Tactic.Naming
+    Ide.Plugin.Tactic.Range
     Ide.Plugin.Tactic.Tactics
+    Ide.Plugin.Tactic.Types
+    Ide.Plugin.Tactic.TestTypes
     Ide.TreeTransform
 
   ghc-options:
@@ -147,8 +155,9 @@ executable haskell-language-server
     , transformers
     , unordered-containers
     , ghc-source-gen
-    , refinery
+    , refinery                 >=0.2.0.0
     , ghc-exactprint
+    , fingertree
 
   if flag(agpl)
     build-depends: brittany
@@ -237,7 +246,8 @@ test-suite func-test
     , tasty-golden
     , tasty-rerun
 
-  hs-source-dirs:     test/functional plugins/default/src
+  hs-source-dirs:     test/functional plugins/tactics/src
+
   main-is:            Main.hs
   other-modules:
     Command
@@ -258,7 +268,7 @@ test-suite func-test
     Symbol
     TypeDefinition
     Tactic
-    Ide.Plugin.Tactic.Types
+    Ide.Plugin.Tactic.TestTypes
 
   ghc-options:
     -Wall -Wno-name-shadowing -threaded -rtsopts -with-rtsopts=-N