Move doctests to shell script

This fixes various problems with doctest:

* https://github.com/sol/doctest/issues/245
* https://github.com/composewell/streamly/issues/83

Also clean up travis.yml for cabal-3.

.travis.yml

@@ -7,18 +7,18 @@ dist: trusty
 
 matrix:
   include:
-    - env: CABALVER=2.2 GHCVER=7.6.3
-      addons: {apt: {packages: [cabal-install-2.2,ghc-7.6.3], sources: [hvr-ghc]}}
-    - env: CABALVER=2.2 GHCVER=7.8.4
-      addons: {apt: {packages: [cabal-install-2.2,ghc-7.8.4], sources: [hvr-ghc]}}
-    - env: CABALVER=2.2 GHCVER=7.10.2
-      addons: {apt: {packages: [cabal-install-2.2,ghc-7.10.2], sources: [hvr-ghc]}}
-    - env: CABALVER=2.2 GHCVER=8.0.1
-      addons: {apt: {packages: [cabal-install-2.2,ghc-8.0.1], sources: [hvr-ghc]}}
-    - env: CABALVER=2.2 GHCVER=8.2.2
-      addons: {apt: {packages: [cabal-install-2.2,ghc-8.2.2], sources: [hvr-ghc]}}
-    - env: CABALVER=2.2 GHCVER=8.4.1
-      addons: {apt: {packages: [cabal-install-2.2,ghc-8.4.1], sources: [hvr-ghc]}}
+    - env: CABALVER=3.0 GHCVER=7.6.3 SKIP_DOCTESTS=yes
+      addons: {apt: {packages: [cabal-install-3.0,ghc-7.6.3], sources: [hvr-ghc]}}
+    - env: CABALVER=3.0 GHCVER=7.8.4 SKIP_DOCTESTS=yes
+      addons: {apt: {packages: [cabal-install-3.0,ghc-7.8.4], sources: [hvr-ghc]}}
+    - env: CABALVER=3.0 GHCVER=7.10.2 SKIP_DOCTESTS=yes
+      addons: {apt: {packages: [cabal-install-3.0,ghc-7.10.2], sources: [hvr-ghc]}}
+    - env: CABALVER=3.0 GHCVER=8.0.1 SKIP_DOCTESTS=yes
+      addons: {apt: {packages: [cabal-install-3.0,ghc-8.0.1], sources: [hvr-ghc]}}
+    - env: CABALVER=3.0 GHCVER=8.2.2
+      addons: {apt: {packages: [cabal-install-3.0,ghc-8.2.2], sources: [hvr-ghc]}}
+    - env: CABALVER=3.0 GHCVER=8.4.1
+      addons: {apt: {packages: [cabal-install-3.0,ghc-8.4.1], sources: [hvr-ghc]}}
     - env: CABALVER=head GHCVER=head
       addons: {apt: {packages: [cabal-install-head,ghc-head],  sources: [hvr-ghc]}}
 
@@ -36,27 +36,15 @@ before_install:
 install:
  - cabal --version
  - travis_retry cabal update
- - cabal sandbox init
- - cabal install --only-dependencies --enable-tests -j
 
 script:
- - cabal configure --enable-tests -v2
  - cabal build
  - cabal test
+ - ./run-doctests.sh
  - cabal check
  - cabal sdist
  - cabal haddock --hyperlink-source --html-location=https://hackage.haskell.org/package/\$pkg-\$version/docs/
-# check that the generated source-distribution can be built & installed
- - export SRC_TGZ=$(cabal info . | awk '{print $2 ".tar.gz";exit}') ;
-   cd dist/;
-   cabal sandbox init;
-   if [ -f "$SRC_TGZ" ]; then
-      cabal install "$SRC_TGZ" --enable-tests;
-   else
-      echo "expected '$SRC_TGZ' not found";
-      exit 1;
-   fi;
-   cd ..
+ - cabal install --enable-tests --lib
 
 after_script:
     - ./update-gh-pages.sh

doctests-hpath.hs

@@ -1,13 +0,0 @@
-module Main where
-
-
-import Test.DocTest
-import Test.HUnit
-
-main =
-    doctest
-      ["-isrc"
-      , "-XOverloadedStrings"
-      , "src/HPath.hs"
-      ]
-

doctests-posix.hs

@@ -1,25 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-
-module Main where
-
-import Control.Applicative
-import System.Posix.Directory.Traversals
-
-import Test.DocTest
-import Test.HUnit
-
-main = do
-    doctest
-      [ "-isrc"
-      , "-XOverloadedStrings"
-      , "System.Posix.FilePath"
-      ]
-    runTestTT unitTests
-
-
-unitTests :: Test
-unitTests = test
-    [ TestCase $ do
-        r <- (==) <$> allDirectoryContents "." <*> allDirectoryContents' "."
-        assertBool "allDirectoryContents == allDirectoryContents'" r
-    ]

hpath.cabal

@@ -13,8 +13,6 @@ cabal-version:       1.14
 extra-source-files:  README.md
                      CHANGELOG
                      cbits/dirutils.h
-                     doctests-hpath.hs
-                     doctests-posix.hs
 
 library
   if os(windows)
@@ -41,7 +39,6 @@ library
                    , deepseq
                    , exceptions
                    , hspec
-                   , simple-sendfile >= 0.2.24
                    , streamly >= 0.7
                    , unix >= 2.5
                    , unix-bytestring
@@ -49,37 +46,6 @@ library
                    , word8
 
 
-test-suite doctests-hpath
-  if os(windows)
-    build-depends: unbuildable<0
-    buildable: False
-  default-language:  Haskell2010
-  type:              exitcode-stdio-1.0
-  ghc-options:       -threaded
-  main-is:           doctests-hpath.hs
-  build-depends:     base
-                   , HUnit
-                   , QuickCheck
-                   , doctest >= 0.8
-                   , hpath
-
-test-suite doctests-posix
-  if os(windows)
-    build-depends: unbuildable<0
-    buildable: False
-  default-language:  Haskell2010
-  type:              exitcode-stdio-1.0
-  ghc-options:       -threaded
-  main-is:           doctests-posix.hs
-  build-depends:     base,
-                     bytestring >= 0.10.0.0,
-                     unix,
-                     hpath,
-                     doctest >= 0.8,
-                     HUnit,
-                     QuickCheck,
-                     word8
-
 test-suite spec
   if os(windows)
     build-depends: unbuildable<0

run-doctests.sh

@@ -0,0 +1,22 @@
+#!/bin/sh
+
+set -e
+
+if [ -n "${SKIP_DOCTESTS}" ] ; then
+    echo "Skipping doctests"
+    exit 0
+fi
+
+if ! command -v doctest >/dev/null ; then
+    tempdir="$(mktemp -d)"
+    (
+     cd "${tempdir}"
+     cabal install --installdir="${tempdir}" doctest
+    )
+    export PATH="${tempdir}:$PATH"
+fi
+
+set -x
+
+cabal exec doctest -- -isrc -XOverloadedStrings System.Posix.FilePath
+cabal exec doctest -- -isrc -XOverloadedStrings HPath