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ghc-plugs-out (empty) → 1.0.0.0

raw patch · 27 files changed

+1164/−0 lines, 27 filesdep +basedep +ghcdep +ghc-plugs-out

Dependencies added: base, ghc, ghc-plugs-out, th-printf

Files

+ LICENSE.md view
@@ -0,0 +1,373 @@+Mozilla Public License Version 2.0+==================================++1. Definitions+--------------++1.1. "Contributor"+    means each individual or legal entity that creates, contributes to+    the creation of, or owns Covered Software.++1.2. "Contributor Version"+    means the combination of the Contributions of others (if any) used+    by a Contributor and that particular Contributor's Contribution.++1.3. "Contribution"+    means Covered Software of a particular Contributor.++1.4. "Covered Software"+    means Source Code Form to which the initial Contributor has attached+    the notice in Exhibit A, the Executable Form of such Source Code+    Form, and Modifications of such Source Code Form, in each case+    including portions thereof.++1.5. "Incompatible With Secondary Licenses"+    means++    (a) that the initial Contributor has attached the notice described+        in Exhibit B to the Covered Software; or++    (b) that the Covered Software was made available under the terms of+        version 1.1 or earlier of the License, but not also under the+        terms of a Secondary License.++1.6. "Executable Form"+    means any form of the work other than Source Code Form.++1.7. "Larger Work"+    means a work that combines Covered Software with other material, in+    a separate file or files, that is not Covered Software.++1.8. "License"+    means this document.++1.9. "Licensable"+    means having the right to grant, to the maximum extent possible,+    whether at the time of the initial grant or subsequently, any and+    all of the rights conveyed by this License.++1.10. "Modifications"+    means any of the following:++    (a) any file in Source Code Form that results from an addition to,+        deletion from, or modification of the contents of Covered+        Software; or++    (b) any new file in Source Code Form that contains any Covered+        Software.++1.11. "Patent Claims" of a Contributor+    means any patent claim(s), including without limitation, method,+    process, and apparatus claims, in any patent Licensable by such+    Contributor that would be infringed, but for the grant of the+    License, by the making, using, selling, offering for sale, having+    made, import, or transfer of either its Contributions or its+    Contributor Version.++1.12. "Secondary License"+    means either the GNU General Public License, Version 2.0, the GNU+    Lesser General Public License, Version 2.1, the GNU Affero General+    Public License, Version 3.0, or any later versions of those+    licenses.++1.13. "Source Code Form"+    means the form of the work preferred for making modifications.++1.14. "You" (or "Your")+    means an individual or a legal entity exercising rights under this+    License. For legal entities, "You" includes any entity that+    controls, is controlled by, or is under common control with You. For+    purposes of this definition, "control" means (a) the power, direct+    or indirect, to cause the direction or management of such entity,+    whether by contract or otherwise, or (b) ownership of more than+    fifty percent (50%) of the outstanding shares or beneficial+    ownership of such entity.++2. License Grants and Conditions+--------------------------------++2.1. Grants++Each Contributor hereby grants You a world-wide, royalty-free,+non-exclusive license:++(a) under intellectual property rights (other than patent or trademark)+    Licensable by such Contributor to use, reproduce, make available,+    modify, display, perform, distribute, and otherwise exploit its+    Contributions, either on an unmodified basis, with Modifications, or+    as part of a Larger Work; and++(b) under Patent Claims of such Contributor to make, use, sell, offer+    for sale, have made, import, and otherwise transfer either its+    Contributions or its Contributor Version.++2.2. Effective Date++The licenses granted in Section 2.1 with respect to any Contribution+become effective for each Contribution on the date the Contributor first+distributes such Contribution.++2.3. Limitations on Grant Scope++The licenses granted in this Section 2 are the only rights granted under+this License. No additional rights or licenses will be implied from the+distribution or licensing of Covered Software under this License.+Notwithstanding Section 2.1(b) above, no patent license is granted by a+Contributor:++(a) for any code that a Contributor has removed from Covered Software;+    or++(b) for infringements caused by: (i) Your and any other third party's+    modifications of Covered Software, or (ii) the combination of its+    Contributions with other software (except as part of its Contributor+    Version); or++(c) under Patent Claims infringed by Covered Software in the absence of+    its Contributions.++This License does not grant any rights in the trademarks, service marks,+or logos of any Contributor (except as may be necessary to comply with+the notice requirements in Section 3.4).++2.4. Subsequent Licenses++No Contributor makes additional grants as a result of Your choice to+distribute the Covered Software under a subsequent version of this+License (see Section 10.2) or under the terms of a Secondary License (if+permitted under the terms of Section 3.3).++2.5. Representation++Each Contributor represents that the Contributor believes its+Contributions are its original creation(s) or it has sufficient rights+to grant the rights to its Contributions conveyed by this License.++2.6. Fair Use++This License is not intended to limit any rights You have under+applicable copyright doctrines of fair use, fair dealing, or other+equivalents.++2.7. Conditions++Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted+in Section 2.1.++3. Responsibilities+-------------------++3.1. Distribution of Source Form++All distribution of Covered Software in Source Code Form, including any+Modifications that You create or to which You contribute, must be under+the terms of this License. You must inform recipients that the Source+Code Form of the Covered Software is governed by the terms of this+License, and how they can obtain a copy of this License. You may not+attempt to alter or restrict the recipients' rights in the Source Code+Form.++3.2. Distribution of Executable Form++If You distribute Covered Software in Executable Form then:++(a) such Covered Software must also be made available in Source Code+    Form, as described in Section 3.1, and You must inform recipients of+    the Executable Form how they can obtain a copy of such Source Code+    Form by reasonable means in a timely manner, at a charge no more+    than the cost of distribution to the recipient; and++(b) You may distribute such Executable Form under the terms of this+    License, or sublicense it under different terms, provided that the+    license for the Executable Form does not attempt to limit or alter+    the recipients' rights in the Source Code Form under this License.++3.3. Distribution of a Larger Work++You may create and distribute a Larger Work under terms of Your choice,+provided that You also comply with the requirements of this License for+the Covered Software. If the Larger Work is a combination of Covered+Software with a work governed by one or more Secondary Licenses, and the+Covered Software is not Incompatible With Secondary Licenses, this+License permits You to additionally distribute such Covered Software+under the terms of such Secondary License(s), so that the recipient of+the Larger Work may, at their option, further distribute the Covered+Software under the terms of either this License or such Secondary+License(s).++3.4. Notices++You may not remove or alter the substance of any license notices+(including copyright notices, patent notices, disclaimers of warranty,+or limitations of liability) contained within the Source Code Form of+the Covered Software, except that You may alter any license notices to+the extent required to remedy known factual inaccuracies.++3.5. Application of Additional Terms++You may choose to offer, and to charge a fee for, warranty, support,+indemnity or liability obligations to one or more recipients of Covered+Software. However, You may do so only on Your own behalf, and not on+behalf of any Contributor. You must make it absolutely clear that any+such warranty, support, indemnity, or liability obligation is offered by+You alone, and You hereby agree to indemnify every Contributor for any+liability incurred by such Contributor as a result of warranty, support,+indemnity or liability terms You offer. You may include additional+disclaimers of warranty and limitations of liability specific to any+jurisdiction.++4. Inability to Comply Due to Statute or Regulation+---------------------------------------------------++If it is impossible for You to comply with any of the terms of this+License with respect to some or all of the Covered Software due to+statute, judicial order, or regulation then You must: (a) comply with+the terms of this License to the maximum extent possible; and (b)+describe the limitations and the code they affect. Such description must+be placed in a text file included with all distributions of the Covered+Software under this License. Except to the extent prohibited by statute+or regulation, such description must be sufficiently detailed for a+recipient of ordinary skill to be able to understand it.++5. Termination+--------------++5.1. The rights granted under this License will terminate automatically+if You fail to comply with any of its terms. However, if You become+compliant, then the rights granted under this License from a particular+Contributor are reinstated (a) provisionally, unless and until such+Contributor explicitly and finally terminates Your grants, and (b) on an+ongoing basis, if such Contributor fails to notify You of the+non-compliance by some reasonable means prior to 60 days after You have+come back into compliance. Moreover, Your grants from a particular+Contributor are reinstated on an ongoing basis if such Contributor+notifies You of the non-compliance by some reasonable means, this is the+first time You have received notice of non-compliance with this License+from such Contributor, and You become compliant prior to 30 days after+Your receipt of the notice.++5.2. If You initiate litigation against any entity by asserting a patent+infringement claim (excluding declaratory judgment actions,+counter-claims, and cross-claims) alleging that a Contributor Version+directly or indirectly infringes any patent, then the rights granted to+You by any and all Contributors for the Covered Software under Section+2.1 of this License shall terminate.++5.3. In the event of termination under Sections 5.1 or 5.2 above, all+end user license agreements (excluding distributors and resellers) which+have been validly granted by You or Your distributors under this License+prior to termination shall survive termination.++************************************************************************+*                                                                      *+*  6. Disclaimer of Warranty                                           *+*  -------------------------                                           *+*                                                                      *+*  Covered Software is provided under this License on an "as is"       *+*  basis, without warranty of any kind, either expressed, implied, or  *+*  statutory, including, without limitation, warranties that the       *+*  Covered Software is free of defects, merchantable, fit for a        *+*  particular purpose or non-infringing. The entire risk as to the     *+*  quality and performance of the Covered Software is with You.        *+*  Should any Covered Software prove defective in any respect, You     *+*  (not any Contributor) assume the cost of any necessary servicing,   *+*  repair, or correction. This disclaimer of warranty constitutes an   *+*  essential part of this License. No use of any Covered Software is   *+*  authorized under this License except under this disclaimer.         *+*                                                                      *+************************************************************************++************************************************************************+*                                                                      *+*  7. Limitation of Liability                                          *+*  --------------------------                                          *+*                                                                      *+*  Under no circumstances and under no legal theory, whether tort      *+*  (including negligence), contract, or otherwise, shall any           *+*  Contributor, or anyone who distributes Covered Software as          *+*  permitted above, be liable to You for any direct, indirect,         *+*  special, incidental, or consequential damages of any character      *+*  including, without limitation, damages for lost profits, loss of    *+*  goodwill, work stoppage, computer failure or malfunction, or any    *+*  and all other commercial damages or losses, even if such party      *+*  shall have been informed of the possibility of such damages. This   *+*  limitation of liability shall not apply to liability for death or   *+*  personal injury resulting from such party's negligence to the       *+*  extent applicable law prohibits such limitation. Some               *+*  jurisdictions do not allow the exclusion or limitation of           *+*  incidental or consequential damages, so this exclusion and          *+*  limitation may not apply to You.                                    *+*                                                                      *+************************************************************************++8. Litigation+-------------++Any litigation relating to this License may be brought only in the+courts of a jurisdiction where the defendant maintains its principal+place of business and such litigation shall be governed by laws of that+jurisdiction, without reference to its conflict-of-law provisions.+Nothing in this Section shall prevent a party's ability to bring+cross-claims or counter-claims.++9. Miscellaneous+----------------++This License represents the complete agreement concerning the subject+matter hereof. If any provision of this License is held to be+unenforceable, such provision shall be reformed only to the extent+necessary to make it enforceable. Any law or regulation which provides+that the language of a contract shall be construed against the drafter+shall not be used to construe this License against a Contributor.++10. Versions of the License+---------------------------++10.1. New Versions++Mozilla Foundation is the license steward. Except as provided in Section+10.3, no one other than the license steward has the right to modify or+publish new versions of this License. Each version will be given a+distinguishing version number.++10.2. Effect of New Versions++You may distribute the Covered Software under the terms of the version+of the License under which You originally received the Covered Software,+or under the terms of any subsequent version published by the license+steward.++10.3. Modified Versions++If you create software not governed by this License, and you want to+create a new license for such software, you may create and use a+modified version of this License if you rename the license and remove+any references to the name of the license steward (except to note that+such modified license differs from this License).++10.4. Distributing Source Code Form that is Incompatible With Secondary+Licenses++If You choose to distribute Source Code Form that is Incompatible With+Secondary Licenses under the terms of this version of the License, the+notice described in Exhibit B of this License must be attached.++Exhibit A - Source Code Form License Notice+-------------------------------------------++  This Source Code Form is subject to the terms of the Mozilla Public+  License, v. 2.0. If a copy of the MPL was not distributed with this+  file, You can obtain one at http://mozilla.org/MPL/2.0/.++If it is not possible or desirable to put the notice in a particular+file, then You may include the notice in a location (such as a LICENSE+file in a relevant directory) where a recipient would be likely to look+for such a notice.++You may add additional accurate notices of copyright ownership.++Exhibit B - "Incompatible With Secondary Licenses" Notice+---------------------------------------------------------++  This Source Code Form is "Incompatible With Secondary Licenses", as+  defined by the Mozilla Public License, v. 2.0.
+ README.rst view
@@ -0,0 +1,307 @@+GHC Plugs Out+=============+Type checker plugins without the type checking.++|cabal-ci|++Introduction+------------+When getting ready to launch, one of the steps is the plugs-out test. Can the+spacecraft function on its own without power or fuel from all cables and+umbilicals?++When debugging GHC plugins, I've added tracing and changed the wiring.  Rather+than throw those edits away, I've collected them in `ghc-plugs-out`_, a package+of tests that don't supply any power or fuel for typechecking. It is the first+multiple library package I've put together [#]_.++Wiring Diagram+--------------+Here's a type checker plugin that doesn't do any solving but instead writes its+call count.++.. code-block:: haskell++    {-# LANGUAGE QuasiQuotes, NamedFieldPuns #-}++    module CallCount.TcPlugin (callCount) where++    import Language.Haskell.Printf (s)+    import Data.IORef (IORef)+    import IOEnv (newMutVar, readMutVar, writeMutVar)+    import TcPluginM (tcPluginIO)+    import TcRnTypes (TcPluginResult(..), TcPlugin(..), unsafeTcPluginTcM)++    newtype State = State { callref :: IORef Int }++    callCount :: TcPlugin+    callCount =+        TcPlugin+            { tcPluginInit = return . State =<< (unsafeTcPluginTcM $ newMutVar 1)++            , tcPluginSolve = \State{callref = c} _ _ _ -> do+                n <- unsafeTcPluginTcM $ readMutVar c+                tcPluginIO . putStrLn $ [s|>>> GHC-TcPlugin #%d|] n+                unsafeTcPluginTcM $ writeMutVar c (n + 1)+                return $ TcPluginOk [] []++            , tcPluginStop = const $ return ()+            }++Plugins are flagged for recompilation in their ``pluginRecompile`` field.+Let's now wire up and test the pure ``CallCount.Pure.Plugin`` and the impure+``CallCount.Impure.Plugin``. The recommended way to wire up a plugin is with+a pragma, only in source files that need the plugin.++.. code-block:: haskell++    {-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++    module Main where++    main :: IO a+    main = undefined++The call count prints on first build but not when there's no work to do.++.. code-block:: pre++    > cabal build test-wireup-pure-by-pragma+    [1 of 1] Compiling Main+    >>> GHC-TcPlugin #1++    > cabal build test-wireup-pure-by-pragma+    Up to date++A plugin can also be wired up with an option, say in a cabal file. This is+probably fine if all your modules need a plugin.++.. code-block:: yaml++    test-suite test-wireup-pure-by-option+      import: opts+      type: exitcode-stdio-1.0+      main-is: Main.hs+      hs-source-dirs: test-suites/wireup-pure-by-option+      ghc-options: -Wall -fplugin CallCount.Pure.Plugin+      build-depends: base, call-count-plugin++.. code-block:: pre++    > cabal build test-wireup-pure-by-option+    [1 of 1] Compiling Main+    >>> GHC-TcPlugin #1++If you mix and match both ways of doing the wiring you'll end up with two+instances of the plugin in the compilation.++.. code-block:: pre++    > cabal build test-wireup-pure-by-both+    [1 of 1] Compiling Main+    >>> GHC-TcPlugin #1+    >>> GHC-TcPlugin #1++If your plugin is impure, it's going to force a recompilation.++.. code-block:: pre++    > cabal build test-wireup-impure-by-pragma+    [1 of 1] Compiling Main+    >>> GHC-TcPlugin #1+    [1 of 1] Compiling Main [Impure plugin forced recompilation]+    >>> GHC-TcPlugin #1++    > cabal build test-wireup-impure-by-option+    [1 of 1] Compiling Main+    >>> GHC-TcPlugin #1+    [1 of 1] Compiling Main [Impure plugin forced recompilation]+    >>> GHC-TcPlugin #1++    > cabal build test-wireup-impure-by-both+    [1 of 1] Compiling Main+    >>> GHC-TcPlugin #1+    >>> GHC-TcPlugin #1+    [1 of 1] Compiling Main [Impure plugin forced recompilation]+    >>> GHC-TcPlugin #1+    >>> GHC-TcPlugin #1++Modularity+----------+GHC compiles modules. We see the counter plugin is called on twice when+functions ``foo`` and ``bar`` are in module ``Main``.++.. code-block:: haskell++    {-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++    module Main where++    foo :: IO a+    foo = undefined++    bar :: IO a+    bar = undefined++    main :: IO ()+    main = return ()++.. code-block:: pre++    > cabal build test-counter-main+    [1 of 1] Compiling Main+    >>> GHC-TcPlugin #1+    >>> GHC-TcPlugin #2++Moving ``foo`` and ``bar`` to module ``FooBar`` and the counter plugin reports+two calls again.++.. code-block:: pre++    > cabal build test-counter-foobar-main+    [1 of 2] Compiling FooBar+    >>> GHC-TcPlugin #1+    >>> GHC-TcPlugin #2+    [2 of 2] Compiling Main++Move these functions into separate modules and we count one call for each module.++.. code-block:: pre++    > cabal build test-counter-foo-bar-main+    [1 of 3] Compiling Bar+    >>> GHC-TcPlugin #1+    [2 of 3] Compiling Foo+    >>> GHC-TcPlugin #1+    [3 of 3] Compiling Main++Undefined is not a Function+---------------------------+If your plugin behaves badly it is going to hurt. GHC panics when any one of+the functions required of a type checker plugin is implemented undefined.++.. code-block:: haskell++    plugin :: Plugin+    plugin = mkPureTcPlugin undefSolve++    undefSolve :: TcPlugin+    undefSolve = noOp { tcPluginSolve = \_ _ _ _ -> undefined }++    noOp :: TcPlugin+    noOp =+        TcPlugin+            { tcPluginInit = return ()+            , tcPluginSolve = \_ _ _ _ -> return $ TcPluginOk [] []+            , tcPluginStop = const $ return ()+            }++    mkPureTcPlugin :: TcPlugin -> Plugin+    mkPureTcPlugin p =+        defaultPlugin+            { tcPlugin = const $ Just p+            , pluginRecompile = purePlugin+            }++.. code-block:: pre++    > cabal build test-undefined-solve+    [1 of 1] Compiling Undefined.Solve.Plugin+    [1 of 1] Compiling Main+    ghc: panic! (the 'impossible' happened)+    Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug++I would have liked to use record update syntax for undefSolve as shown above+but this is not yet possible [#]_ with GHC when the data type has an+existential qualifier and that is how TcPlugin is defined [#]_.++.. code-block:: haskell++    data TcPlugin = forall s. TcPlugin+        { tcPluginInit  :: TcPluginM s+        -- ^ Initialize plugin, when entering type-checker.+        , tcPluginSolve :: s -> TcPluginSolver+        -- ^ Solve some constraints.+        -- TODO: WRITE MORE DETAILS ON HOW THIS WORKS.+        , tcPluginStop  :: s -> TcPluginM ()+        -- ^ Clean up after the plugin, when exiting the type-checker.+        }++Care Free+---------+Type checker plugins are of course called on by GHC to resolve constraints.+Some need solving and others don't. GHC knows that it can get an ``a`` from+``undefined`` but maybe a plugin can do better so we get called.++.. code-block:: haskell++    {-# OPTIONS_GHC -fplugin Undefined.Solve.Plugin #-}+    module Main where++    main :: IO a+    main = undefined++Going from ``()`` to ``()`` needs no further resolution. GHC can handle this+by itself. The ``test-undefined-*-carefree`` test suites have these mains.+The ones without carefree in their name don't. They have the ``a`` from+``undefined`` mains.++.. code-block:: haskell++    {-# OPTIONS_GHC -fplugin Undefined.Solve.Plugin #-}+    module Main where++    main :: IO ()+    main = return ()++So we've seen that a typechecker plugin's solve function **may** be called but+its init and stop functions are **always** called.++.. code-block:: ascii++  +-------------------------------+------------++  | Test Suite                    | GHC Panics |+  +===============================+============++  | test-undefined-init           |     x      |+  +-------------------------------+------------++  | test-undefined-init-carefree  |     x      |+  +-------------------------------+------------++  | test-undefined-solve          |     x      |+  +-------------------------------+------------++  | test-undefined-solve-carefree |            |+  +-------------------------------+------------++  | test-undefined-stop           |     x      |+  +-------------------------------+------------++  | test-undefined-stop-carefree  |     x      |+  +-------------------------------+------------+++Takeaways+---------+* We should wire up type checker plugins with pragmas only in modules that need+  it.+* Don't forget to flag pure plugins as such.+* If GHC doesn't need help resolving constraints then it won't call out to your plugin.+* Modules are the units of compilation.++License+-------+.. code-block:: ascii++    Copyright © Phil de Joux 2017-2020+    Copyright © Block Scope Limited 2017-2020++This software is subject to the terms of the Mozilla Public License, v2.0. If+a copy of the MPL was not distributed with this file, you can obtain one at+http://mozilla.org/MPL/2.0/.++.. _ghc-plugs-out: https://github.com/BlockScope/ghc-plugs-out++.. _ghc-2595: https://gitlab.haskell.org/ghc/ghc/issues/2595++.. _fgaz-GSoC-2018: https://fgaz.me/posts/2019-11-14-cabal-multiple-libraries/++.. [#] Multiple libraries were added to cabal 3.0, see fgaz-GSoC-2018_.+.. [#] The error if you try is "Record update for insufficiently polymorphic field", see ghc-2595_.+.. [#] These field haddock comments are verbatim from the GHC source.++.. |cabal-ci| image:: https://github.com/BlockScope/ghc-plugs-out/workflows/cabal/badge.svg
+ changelog.md view
@@ -0,0 +1,5 @@+# Versions of ghc-plugs-out++## 1.0.0.0 Initial Release+Add tests that show how typechecker plugins interact with GHC depending on+their purity, how they're wired up and whether GHC needs help typechecking.
+ ghc-plugs-out.cabal view
@@ -0,0 +1,246 @@+cabal-version: 3.0++name:           ghc-plugs-out+version:        1.0.0.0+synopsis:       Type checker plugins without the type checking.+description:+  Tests that show how typechecker plugins interact with GHC depending on their+  purity, how they're wired up and whether GHC needs help typechecking.+category:       Compiler Plugin+author:         Phil de Joux+maintainer:     phil.dejoux@blockscope.com+copyright:      © 2020 Phil de Joux, © 2020 Block Scope Limited+homepage:       https://github.com/blockscope/ghc-plugs-out+license:        MPL-2.0+license-file:   LICENSE.md+tested-with:    GHC == 8.8.3, GHC == 8.10.1+build-type:     Simple+extra-source-files:+  changelog.md, README.rst++source-repository head+  type: git+  location: https://github.com/blockscope/ghc-plugs-out++common opts+  ghc-options:+    -Wall+    -Wincomplete-uni-patterns+    -Wcompat+    -Widentities+    -Wredundant-constraints+    -fhide-source-paths+  default-language: Haskell2010++library no-op-plugin+  import: opts+  exposed-modules:+      NoOp.Plugin+  hs-source-dirs:+      plugins/noop+  build-depends:+      base >= 4.13 && < 5+    , ghc++library undefined-init-plugin+  import: opts+  exposed-modules:+      Undefined.Init.Plugin+  hs-source-dirs:+      plugins/init+  build-depends:+      base >= 4.13 && < 5+    , ghc+    , no-op-plugin++library undefined-solve-plugin+  import: opts+  exposed-modules:+      Undefined.Solve.Plugin+  hs-source-dirs:+      plugins/solve+  build-depends:+      base >= 4.13 && < 5+    , ghc+    , no-op-plugin++library undefined-stop-plugin+  import: opts+  exposed-modules:+      Undefined.Stop.Plugin+  hs-source-dirs:+      plugins/stop+  build-depends:+      base >= 4.13 && < 5+    , ghc+    , no-op-plugin++library call-count-plugin+  import: opts+  exposed-modules:+      CallCount.TcPlugin+      CallCount.Pure.Plugin+      CallCount.Impure.Plugin+  hs-source-dirs:+      plugins/call-count+  build-depends:+      base >= 4.13 && < 5+    , ghc+    , th-printf+    , no-op-plugin++test-suite test-undefined-init+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/undef-init+  build-depends:+      base >= 4.13 && < 5+    , undefined-init-plugin++test-suite test-undefined-init-carefree+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/undef-init-carefree+  build-depends:+      base >= 4.13 && < 5+    , undefined-init-plugin++test-suite test-undefined-solve+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/undef-solve+  build-depends:+      base >= 4.13 && < 5+    , undefined-solve-plugin++test-suite test-undefined-solve-carefree+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/undef-solve-carefree+  build-depends:+      base >= 4.13 && < 5+    , undefined-solve-plugin++test-suite test-undefined-stop+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/undef-stop+  build-depends:+      base >= 4.13 && < 5+    , undefined-stop-plugin++test-suite test-undefined-stop-carefree+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/undef-stop-carefree+  build-depends:+      base >= 4.13 && < 5+    , undefined-stop-plugin++test-suite test-wireup-pure-by-option+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/wireup-pure-by-option+  ghc-options: -Wall -fplugin CallCount.Pure.Plugin+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-wireup-pure-by-pragma+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/wireup-pure-by-pragma+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-wireup-pure-by-both+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/wireup-pure-by-pragma+  ghc-options: -Wall -fplugin CallCount.Pure.Plugin+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-wireup-impure-by-option+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/wireup-impure-by-option+  ghc-options: -Wall -fplugin CallCount.Impure.Plugin+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-wireup-impure-by-pragma+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/wireup-impure-by-pragma+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-wireup-impure-by-both+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/wireup-impure-by-pragma+  ghc-options: -Wall -fplugin CallCount.Impure.Plugin+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-counter-main+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  hs-source-dirs:+      test-suites/counter-main+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-counter-foo-bar-main+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  other-modules: Foo Bar+  hs-source-dirs:+      test-suites/counter-foo-bar-main+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin++test-suite test-counter-foobar-main+  import: opts+  type: exitcode-stdio-1.0+  main-is: Main.hs+  other-modules: FooBar+  hs-source-dirs:+      test-suites/counter-foobar-main+  build-depends:+      base >= 4.13 && < 5+    , call-count-plugin
+ plugins/call-count/CallCount/Impure/Plugin.hs view
@@ -0,0 +1,8 @@+module CallCount.Impure.Plugin (plugin) where++import Plugins (Plugin)+import NoOp.Plugin (mkImpureTcPlugin)+import CallCount.TcPlugin (callCount)++plugin :: Plugin+plugin = mkImpureTcPlugin callCount
+ plugins/call-count/CallCount/Pure/Plugin.hs view
@@ -0,0 +1,8 @@+module CallCount.Pure.Plugin (plugin) where++import Plugins (Plugin)+import NoOp.Plugin (mkPureTcPlugin)+import CallCount.TcPlugin (callCount)++plugin :: Plugin+plugin = mkPureTcPlugin callCount
+ plugins/call-count/CallCount/TcPlugin.hs view
@@ -0,0 +1,25 @@+{-# LANGUAGE QuasiQuotes, NamedFieldPuns #-}++module CallCount.TcPlugin (callCount) where++import Language.Haskell.Printf (s)+import Data.IORef (IORef)+import IOEnv (newMutVar, readMutVar, writeMutVar)+import TcPluginM (tcPluginIO)+import TcRnTypes (TcPluginResult(..), TcPlugin(..), unsafeTcPluginTcM)++newtype State = State{callref :: IORef Int}++callCount :: TcPlugin+callCount =+    TcPlugin+        { tcPluginInit = return . State =<< (unsafeTcPluginTcM $ newMutVar 1)++        , tcPluginSolve = \State{callref = c} _ _ _ -> do+            n <- unsafeTcPluginTcM $ readMutVar c+            tcPluginIO . putStrLn $ [s|>>> GHC-TcPlugin #%d|] n+            unsafeTcPluginTcM $ writeMutVar c (n + 1)+            return $ TcPluginOk [] []++        , tcPluginStop = const $ return ()+        }
+ plugins/init/Undefined/Init/Plugin.hs view
@@ -0,0 +1,7 @@+module Undefined.Init.Plugin (plugin) where++import Plugins (Plugin)+import NoOp.Plugin (undefInit, mkPureTcPlugin)++plugin :: Plugin+plugin = mkPureTcPlugin undefInit
+ plugins/noop/NoOp/Plugin.hs view
@@ -0,0 +1,70 @@+{-# LANGUAGE RankNTypes #-}++module NoOp.Plugin+    ( plugin+    , noOp, undefInit, undefSolve, undefStop+    , mkPureTcPlugin, mkImpureTcPlugin+    ) where++import Plugins (Plugin(..), tcPlugin, defaultPlugin, purePlugin, impurePlugin)+import TcRnTypes (TcPluginResult(..), TcPlugin(..))++plugin :: Plugin+plugin = mkPureTcPlugin noOp++noOp :: TcPlugin+noOp =+    TcPlugin+        { tcPluginInit = return ()+        , tcPluginSolve = \_ _ _ _ -> return $ TcPluginOk [] []+        , tcPluginStop = const $ return ()+        }++-- WARNING: Can't use record update syntax for existentially qualified types.+-- SEE: https://gitlab.haskell.org/ghc/ghc/issues/2595+-- data TcPlugin = forall s. TcPlugin+--   { tcPluginInit  :: TcPluginM s+--   , tcPluginSolve :: s -> TcPluginSolver+--   , tcPluginStop  :: s -> TcPluginM ()+--   }++-- noOp { tcPluginInit = undefined }+undefInit :: TcPlugin+undefInit =+    TcPlugin+        { tcPluginInit = undefined+        , tcPluginSolve = \_ _ _ _ -> return $ TcPluginOk [] []+        , tcPluginStop = const $ return ()+        }++-- noOp { tcPluginSolve = \_ _ _ _ -> undefined }+undefSolve :: TcPlugin+undefSolve =+    TcPlugin+        { tcPluginInit = return ()+        , tcPluginSolve = \_ _ _ _ -> undefined+        , tcPluginStop = const $ return ()+        }++-- noOp { tcPluginStop = const undefined }+undefStop :: TcPlugin+undefStop =+    TcPlugin+        { tcPluginInit = return ()+        , tcPluginSolve = \_ _ _ _ -> return $ TcPluginOk [] []+        , tcPluginStop = const undefined+        }++mkPureTcPlugin :: TcPlugin -> Plugin+mkPureTcPlugin p =+    defaultPlugin+        { tcPlugin = const $ Just p+        , pluginRecompile = purePlugin+        }++mkImpureTcPlugin :: TcPlugin -> Plugin+mkImpureTcPlugin p =+    defaultPlugin+        { tcPlugin = const $ Just p+        , pluginRecompile = impurePlugin+        }
+ plugins/solve/Undefined/Solve/Plugin.hs view
@@ -0,0 +1,7 @@+module Undefined.Solve.Plugin (plugin) where++import Plugins (Plugin)+import NoOp.Plugin (undefSolve, mkPureTcPlugin)++plugin :: Plugin+plugin = mkPureTcPlugin undefSolve
+ plugins/stop/Undefined/Stop/Plugin.hs view
@@ -0,0 +1,7 @@+module Undefined.Stop.Plugin (plugin) where++import Plugins (Plugin)+import NoOp.Plugin (undefStop, mkPureTcPlugin)++plugin :: Plugin+plugin = mkPureTcPlugin undefStop
+ test-suites/counter-foo-bar-main/Bar.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++module Bar where++bar :: IO a+bar = undefined
+ test-suites/counter-foo-bar-main/Foo.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++module Foo where++foo :: IO a+foo = undefined
+ test-suites/counter-foo-bar-main/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++module Main where++main :: IO ()+main = return ()
+ test-suites/counter-foobar-main/FooBar.hs view
@@ -0,0 +1,9 @@+{-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++module FooBar where++foo :: IO a+foo = undefined++bar :: IO a+bar = undefined
+ test-suites/counter-foobar-main/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++module Main where++main :: IO ()+main = return ()
+ test-suites/counter-main/Main.hs view
@@ -0,0 +1,12 @@+{-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++module Main where++foo :: IO a+foo = undefined++bar :: IO a+bar = undefined++main :: IO ()+main = return ()
+ test-suites/undef-init-carefree/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin Undefined.Init.Plugin #-}++module Main where++main :: IO ()+main = return ()
+ test-suites/undef-init/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin Undefined.Init.Plugin #-}++module Main where++main :: IO a+main = undefined
+ test-suites/undef-solve-carefree/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin Undefined.Solve.Plugin #-}++module Main where++main :: IO ()+main = return ()
+ test-suites/undef-solve/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin Undefined.Solve.Plugin #-}++module Main where++main :: IO a+main = undefined
+ test-suites/undef-stop-carefree/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin Undefined.Stop.Plugin #-}++module Main where++main :: IO ()+main = return ()
+ test-suites/undef-stop/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin Undefined.Stop.Plugin #-}++module Main where++main :: IO a+main = undefined
+ test-suites/wireup-impure-by-option/Main.hs view
@@ -0,0 +1,4 @@+module Main where++main :: IO a+main = undefined
+ test-suites/wireup-impure-by-pragma/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin CallCount.Impure.Plugin #-}++module Main where++main :: IO a+main = undefined
+ test-suites/wireup-pure-by-option/Main.hs view
@@ -0,0 +1,4 @@+module Main where++main :: IO a+main = undefined
+ test-suites/wireup-pure-by-pragma/Main.hs view
@@ -0,0 +1,6 @@+{-# OPTIONS_GHC -fplugin CallCount.Pure.Plugin #-}++module Main where++main :: IO a+main = undefined