Chrismwendt support hole fill via auto

lib/completion-backend/completion-backend.coffee

@@ -343,16 +343,26 @@ class CompletionBackend
     position = Range.fromPointWithDelta(position, 0, 0) if position?
     prefix = prefix.slice 1 if prefix.startsWith '_'
     @process.getTypeInBuffer(buffer, position).then ({type}) =>
-      @getSymbolsForBuffer(buffer).then (symbols) ->
+      @getSymbolsForBuffer(buffer).then (symbols) =>
         ts = symbols.filter (s) ->
           return false unless s.typeSignature?
           tl = s.typeSignature.split(' -> ').slice(-1)[0]
           return false if tl.match(/^[a-z]$/)
           ts = tl.replace(/[.?*+^$[\]\\(){}|-]/g, "\\$&")
           rx = RegExp ts.replace(/\b[a-z]\b/g, '.+'), ''
           rx.test(type)
-        if prefix.length is 0
-          ts.sort (a, b) ->
-            FZ.score(b.typeSignature, type) - FZ.score(a.typeSignature, type)
-        else
-          FZ.filter ts, prefix, key: 'qname'
+        ts2 =
+          if prefix.length is 0
+            ts.sort (a, b) ->
+              FZ.score(b.typeSignature, type) - FZ.score(a.typeSignature, type)
+          else
+            FZ.filter ts, prefix, key: 'qname'
+        @process.doHoleFill(buffer, position).then ({suggestions}) ->
+          return ts2 unless suggestions?
+          ts2.unshift (suggestions.map (text) ->
+            name: text
+            qname: text
+            typeSignature: type
+            symbolType: 'snippet'
+            )...
+          return ts2

lib/ghc-mod/ghc-modi-process-real.coffee

@@ -3,14 +3,18 @@ CP = require('child_process')
 InteractiveProcess = require './interactive-process'
 {debug, warn, mkError, withTempFile, EOT} = Util = require '../util'
 {EOL} = require('os')
+_ = require 'underscore-plus'
 
 module.exports =
 class GhcModiProcessReal
   constructor: (@caps, @rootDir, @options) ->
     @disposables = new CompositeDisposable
     @disposables.add @emitter = new Emitter
 
-  run: ({interactive, command, text, uri, dashArgs, args, suppressErrors}) ->
+  run: ({interactive, command, text, uri, dashArgs, args, suppressErrors, timeout}) ->
+    if timeout? and interactive
+      throw new Error('Can not have interactive action with set timeout! This
+                       is an error in haskell-ghc-mod. Please report it.')
     args ?= []
     dashArgs ?= []
     if atom.config.get('haskell-ghc-mod.lowMemorySystem')
@@ -25,9 +29,9 @@ class GhcModiProcessReal
     P =
       if text? and not @caps.fileMap
         withTempFile text, uri, (tempuri) ->
-          fun {command, uri: tempuri, args}
+          fun {command, uri: tempuri, args, timeout}
       else
-        fun {command, text, uri, args}
+        fun {command, text, uri, args, timeout}
     P.catch (err) =>
       debug err
       if err.name is 'InteractiveActionTimeout'
@@ -44,6 +48,10 @@ class GhcModiProcessReal
             """
           stack: err.stack
           dismissable: true
+        return []
+      else if err.name is 'NonInteractiveActionTimeout'
+        warn err
+        return []
       else if not suppressErrors
         atom.notifications.addFatalError "
           Haskell-ghc-mod: ghc-mod
@@ -77,7 +85,7 @@ class GhcModiProcessReal
       @proc = null
     return @proc
 
-  runModCmd: ({command, text, uri, args}) =>
+  runModCmd: ({command, text, uri, args, timeout}) =>
     modPath = atom.config.get('haskell-ghc-mod.ghcModPath')
     result = []
     err = []
@@ -88,7 +96,7 @@ class GhcModiProcessReal
     if text?
       cmd = ['--map-file', uri].concat cmd
     stdin = "#{text}#{EOT}" if text?
-    Util.execPromise modPath, cmd, @options, stdin
+    Util.execPromise modPath, cmd, _.extend({timeout}, @options), stdin
     .then (stdout) ->
       stdout.split(EOL).slice(0, -1).map (line) -> line.replace /\0/g, '\n'
 

lib/ghc-mod/ghc-modi-process.coffee

@@ -338,6 +338,28 @@ class GhcModiProcess
           ]
         replacement: text
 
+  doHoleFill: (buffer, crange) =>
+    return Promise.resolve [] unless buffer.getUri()?
+    crange = Util.tabShiftForRange(buffer, crange)
+    @queueCmd 'typeinfo',
+      interactive: false
+      buffer: buffer
+      command: 'auto'
+      uri: buffer.getUri()
+      text: buffer.getText() if buffer.isModified()
+      args: [crange.start.row + 1, crange.start.column + 1]
+      timeout: 5000 # TODO: Make configurable
+    .then (lines) ->
+      return {} if lines.length == 0 or lines[1] == ""
+
+      [line_, rowstart, colstart, rowend, colend, text] = lines[0].match(/^(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/)
+
+      range: Range.fromObject [
+        [parseInt(rowstart) - 1, parseInt(colstart) - 1],
+        [parseInt(rowend) - 1, parseInt(colend) - 1]
+      ]
+      suggestions: lines[1..]
+
   doSigFill: (buffer, crange) =>
     return Promise.resolve [] unless buffer.getUri()?
     crange = Util.tabShiftForRange(buffer, crange)

lib/util.coffee

@@ -58,6 +58,8 @@ module.exports = Util =
           Util.warn("Running #{cmd} #{args} failed with ", error)
           Util.warn stdout if stdout
           error.stack = (new Error).stack
+          if child.killed and opts.timeout?
+            error.name = 'NonInteractiveActionTimeout'
           reject error
         else
           Util.debug "Got response from #{cmd} #{args}", stdout: stdout, stderr: stderr