Implement the HIE Bios

.gitmodules

@@ -34,6 +34,11 @@
 
 [submodule "submodules/floskell"]
 	path = submodules/floskell
-	url = https://github.com/ennocramer/floskell
 	# url = https://github.com/alanz/floskell
-
+  url = https://github.com/ennocramer/floskell
+[submodule "haskell-lsp"]
+	path = haskell-lsp
+	url = https://github.com/mpickering/haskell-lsp.git
+[submodule "lsp-test"]
+	path = lsp-test
+	url = https://github.com/mpickering/lsp-test

app/MainHie.hs

@@ -27,7 +27,7 @@ import           Haskell.Ide.Engine.Plugin.Base
 import           Haskell.Ide.Engine.Plugin.Brittany
 import           Haskell.Ide.Engine.Plugin.Build
 import           Haskell.Ide.Engine.Plugin.Example2
-import           Haskell.Ide.Engine.Plugin.GhcMod
+import           Haskell.Ide.Engine.Plugin.Bios
 import           Haskell.Ide.Engine.Plugin.HaRe
 import           Haskell.Ide.Engine.Plugin.Haddock
 import           Haskell.Ide.Engine.Plugin.HfaAlign
@@ -37,6 +37,7 @@ import           Haskell.Ide.Engine.Plugin.Liquid
 import           Haskell.Ide.Engine.Plugin.Package
 import           Haskell.Ide.Engine.Plugin.Pragmas
 import           Haskell.Ide.Engine.Plugin.Floskell
+import           Haskell.Ide.Engine.Plugin.Generic
 
 -- ---------------------------------------------------------------------
 
@@ -52,7 +53,7 @@ plugins includeExamples = pluginDescToIdePlugins allPlugins
       , baseDescriptor        "base"
       , brittanyDescriptor    "brittany"
       , buildPluginDescriptor "build"
-      , ghcmodDescriptor      "ghcmod"
+      -- , ghcmodDescriptor      "ghcmod"
       , haddockDescriptor     "haddock"
       , hareDescriptor        "hare"
       , hoogleDescriptor      "hoogle"
@@ -61,6 +62,8 @@ plugins includeExamples = pluginDescToIdePlugins allPlugins
       , packageDescriptor     "package"
       , pragmasDescriptor     "pragmas"
       , floskellDescriptor    "floskell"
+      , biosDescriptor        "bios"
+      , genericDescriptor     "generic"
       ]
     examplePlugins =
       [example2Descriptor "eg2"

cabal.project

@@ -1,10 +1,17 @@
 packages:
          ./
          ./hie-plugin-api/
+         ./hie-bios/
+         ./haskell-lsp/
+         ./lsp-test
 
          ./submodules/HaRe
          ./submodules/brittany
          ./submodules/cabal-helper/
          ./submodules/floskell
          ./submodules/ghc-mod/
          ./submodules/ghc-mod/core/
+         ./submodules/floskell
+
+allow-newer: floskell:all
+

haskell-ide-engine.cabal

@@ -32,6 +32,7 @@ library
                        Haskell.Ide.Engine.Plugin.Floskell
                        Haskell.Ide.Engine.Plugin.Fuzzy
                        Haskell.Ide.Engine.Plugin.GhcMod
+                       Haskell.Ide.Engine.Plugin.Bios
                        Haskell.Ide.Engine.Plugin.HaRe
                        Haskell.Ide.Engine.Plugin.Haddock
                        Haskell.Ide.Engine.Plugin.HieExtras
@@ -42,6 +43,7 @@ library
                        Haskell.Ide.Engine.Plugin.Package
                        Haskell.Ide.Engine.Plugin.Package.Compat
                        Haskell.Ide.Engine.Plugin.Pragmas
+                       Haskell.Ide.Engine.Plugin.Generic
                        Haskell.Ide.Engine.Transport.JsonStdio
                        Haskell.Ide.Engine.Transport.LspStdio
                        Haskell.Ide.Engine.Types
@@ -94,6 +96,8 @@ library
                      , vector
                      , yaml >= 0.8.31
                      , yi-rope
+                     , hie-bios
+                     , bytestring-trie
   ghc-options:         -Wall -Wredundant-constraints
   if flag(pedantic)
      ghc-options:      -Werror

hie-bios/.travis.yml

@@ -0,0 +1,34 @@
+# NB: don't set `language: haskell` here
+
+# The following enables several GHC versions to be tested; often it's enough to test only against the last release in a major GHC version. Feel free to omit lines listings versions you don't need/want testing for.
+env:
+ - CABALVER=1.24 GHCVER=8.0.2
+ - CABALVER=2.0  GHCVER=8.2.2
+ - CABALVER=2.2  GHCVER=8.4.4
+ - CABALVER=2.4  GHCVER=8.6.3
+ - CABALVER=head GHCVER=head   # see section about GHC HEAD snapshots
+
+matrix:
+  allow_failures:
+   - env: CABALVER=head GHCVER=head
+
+# Note: the distinction between `before_install` and `install` is not important.
+before_install:
+ - travis_retry sudo add-apt-repository -y ppa:hvr/ghc
+ - travis_retry sudo apt-get update
+ - travis_retry sudo apt-get install cabal-install-$CABALVER ghc-$GHCVER happy alex
+ - export PATH=/opt/ghc/$GHCVER/bin:/opt/cabal/$CABALVER/bin:$PATH
+
+install:
+ - cabal --version
+ - echo "$(ghc --version) [$(ghc --print-project-git-commit-id 2> /dev/null || echo '?')]"
+ - travis_retry cabal update
+ - cabal install --only-dependencies --enable-tests --enable-benchmarks
+
+# Here starts the actual work to be performed for the package under test; any command which exits with a non-zero exit code causes the build to fail.
+script:
+ - if [ -f configure.ac ]; then autoreconf -i; fi
+ - cabal configure --enable-tests --enable-benchmarks -v2  # -v2 provides useful information for debugging
+ - cabal build   # this builds all libraries and executables (including tests/benchmarks)
+ - cabal test
+ - cabal check

hie-bios/ChangeLog

@@ -0,0 +1,2 @@
+2018-12-18 v0.0.0
+	* First release

hie-bios/LICENSE

@@ -0,0 +1,29 @@
+Copyright (c) 2009, IIJ Innovation Institute Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+
+  * Redistributions of source code must retain the above copyright
+    notice, this list of conditions and the following disclaimer.
+  * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in
+    the documentation and/or other materials provided with the
+    distribution.
+  * Neither the name of the copyright holders nor the names of its
+    contributors may be used to endorse or promote products derived
+    from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.

hie-bios/README.md

@@ -0,0 +1,132 @@
+# hie-bios
+
+`hie-bios` is the way which `hie` sets up a GHC API session.
+
+Its design is motivated by the guiding principle:
+
+> It is the responsibility of the build tool to describe the environment
+>  which a package should be built in.
+
+This means that it is possible
+to easily support a wide range of tools including `cabal-install`, `stack`,
+`rules_haskell`, `hadrian` and `obelisk` without major contortions.
+`hie-bios` does not depend on the `Cabal` library nor does not
+read any complicated build products and so on.
+
+How does a tool specify a session? A session is fully specified by a set of
+standard GHC flags. Most tools already produce this information if they support
+a `repl` command. Launching a repl is achieved by calling `ghci` with the
+right flags to specify the package database. `hie-bios` needs a way to get
+these flags and then it can set up GHC API session correctly.
+
+Futher it means that any failure to set up the API session is the responsibility
+of the build tool. It is up to them to provide the correct information if they
+want HIE to work correctly.
+
+## Explicit Configuration
+
+The user can place a `hie.dhall` file in the root of the workspace which
+describes how to setup the environment. For example, to explicitly state
+that you want to use `stack` then the configuration file would look like:
+
+```
+{ cradle = CradleConfig.Stack {=} }
+```
+
+If you use `cabal` then you probably need to specify which component you want
+to use.
+
+```
+{ cradle = CradleConfig.Cabal { component = Some "lib:haskell-ide-engine" } }
+```
+
+Or you can explicitly state the program which should be used to collect
+the options by supplying the path to the program. It is interpreted
+relative to the current working directory if it is not an absolute path.
+
+```
+{ cradle = CradleConfig.Bios { prog = ".hie-bios" } }
+```
+
+The complete dhall configuration is described by the following type
+
+```
+< cradle :
+< Cabal : { component : Optional Text }
+  | Stack : {}
+  | Bazel : {}
+  | Obelisk : {}
+  | Bios : { prog : Text}
+  | Default : {} > >
+```
+
+## Implicit Configuration
+
+There are several built in modes which captures most common Haskell development
+scenarios. If no `hie.dhall` configuration file is found then an implicit
+configuration is searched for.
+
+### Priority
+
+The targets are searched for in following order.
+
+1. A specific `hie-bios` file.
+2. An `obelisk` project
+3. A `rules_haskell` project
+4. A `stack` project
+4. A `cabal` project
+5. The default cradle which has no specific options.
+
+### `cabal-install`
+
+The workspace root is the first folder containing a `cabal.project` file.
+
+The arguments are collected by running `cabal v2-repl`.
+
+If `cabal v2-repl` fails, then the user needs to configure the correct
+target to use by writing a `hie.dhall` file.
+
+### `rules_haskell`
+
+The workspace root is the folder containing a `WORKSPACE` file.
+
+The options are collected by querying `bazel`.
+
+### `obelisk`
+
+The workspace root is the folder containing a `.obelisk` directory.
+
+The options are collected by running `ob ide-args`.
+
+### `bios`
+
+The most general form is the `bios` mode which allows a user to specify themselves
+which flags to provide.
+
+In this mode, an executable file called `.hie-bios` is placed in the root
+of the workspace directory. The script takes one argument, the filepath
+to the current file we want to load into the session. The script returns
+the correct arguments in order to load that file successfully.
+
+A good guiding specification for this file is that the following command
+should work for any file in your project.
+
+```
+ghci $(./hie-bios /path/to/foo.hs) /path/to/foo.hs
+```
+
+This is useful if you are designing a new build system or the other modes
+fail to setup the correct session for some reason. For example, this is
+how hadrian (GHC's build system) is integrated into HIE.
+
+
+## Relationship with `ghcid`
+
+The design of `hie-bios` is inspired by `ghcid`. Like `ghcid`, it does not depend
+on any of the tools it supports. The success of `ghcid` is that it works reliably
+in many situations. This is because of the fact that it delegates complicated
+decisions about a build to the build tool.
+
+`ghcid` could be implemented using `hie-bios` using the `ghci $(./hie-bios Main.hs) Main.hs`
+idiom described earlier.
+

hie-bios/Setup.hs

@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain

hie-bios/cabal.project

@@ -0,0 +1 @@
+packages: .

hie-bios/default.nix

@@ -0,0 +1 @@
+let pkgs = import ./nix {}; in pkgs.packages

hie-bios/exe/biosc.hs

@@ -0,0 +1,82 @@
+{-# LANGUAGE DeriveDataTypeable #-}
+
+module Main where
+
+import Config (cProjectVersion)
+
+import Control.Exception (Exception, Handler(..), ErrorCall(..))
+import qualified Control.Exception as E
+import Data.Typeable (Typeable)
+import Data.Version (showVersion)
+import System.Directory (getCurrentDirectory)
+import System.Environment (getArgs)
+import System.Exit (exitFailure)
+import System.IO (hPutStr, hPutStrLn, stdout, stderr, hSetEncoding, utf8)
+
+import HIE.Bios
+import HIE.Bios.Types
+import HIE.Bios.Check
+import HIE.Bios.Debug
+import Paths_hie_bios
+
+----------------------------------------------------------------
+
+progVersion :: String
+progVersion = "biosc version " ++ showVersion version ++ " compiled by GHC " ++ cProjectVersion ++ "\n"
+
+ghcOptHelp :: String
+ghcOptHelp = " [-g GHC_opt1 -g GHC_opt2 ...] "
+
+usage :: String
+usage =    progVersion
+        ++ "Usage:\n"
+        ++ "\t biosc check" ++ ghcOptHelp ++ "<HaskellFiles...>\n"
+        ++ "\t biosc version\n"
+        ++ "\t biosc help\n"
+
+----------------------------------------------------------------
+
+data HhpcError = SafeList
+               | TooManyArguments String
+               | NoSuchCommand String
+               | CmdArg [String]
+               | FileNotExist String deriving (Show, Typeable)
+
+instance Exception HhpcError
+
+----------------------------------------------------------------
+
+main :: IO ()
+main = flip E.catches handlers $ do
+    hSetEncoding stdout utf8
+    args <- getArgs
+    cradle <- getCurrentDirectory >>= findCradle
+    let cmdArg0 = args !. 0
+        remainingArgs = tail args
+        opt = defaultOptions
+    res <- case cmdArg0 of
+      "check"   -> checkSyntax opt cradle remainingArgs
+      "expand"  -> expandTemplate opt cradle remainingArgs
+      "debug"   -> debugInfo opt cradle
+      "root"    -> rootInfo opt cradle
+      "version" -> return progVersion
+      cmd       -> E.throw (NoSuchCommand cmd)
+    putStr res
+  where
+    handlers = [Handler (handleThenExit handler1), Handler (handleThenExit handler2)]
+    handleThenExit handler e = handler e >> exitFailure
+    handler1 :: ErrorCall -> IO ()
+    handler1 = print -- for debug
+    handler2 :: HhpcError -> IO ()
+    handler2 SafeList = return ()
+    handler2 (TooManyArguments cmd) = do
+        hPutStrLn stderr $ "\"" ++ cmd ++ "\": Too many arguments"
+    handler2 (NoSuchCommand cmd) = do
+        hPutStrLn stderr $ "\"" ++ cmd ++ "\" not supported"
+    handler2 (CmdArg errs) = do
+        mapM_ (hPutStr stderr) errs
+    handler2 (FileNotExist file) = do
+        hPutStrLn stderr $ "\"" ++ file ++ "\" not found"
+    xs !. idx
+      | length xs <= idx = E.throw SafeList
+      | otherwise = xs !! idx