Update Travis-CI build instructions.

- Update ghc-8.6.2 to 8.6.3.

- We don't use installed constraints, so we don't need a separate build step
  that builds without them.

- Use latest make-travis-yml generator and drop the container-based build
  environment. Closes #10.

- Enable install-examples flag to make sure the examples get built.

Author: peti

.travis.yml

@@ -1,11 +1,10 @@
 # This Travis job script has been generated by a script via
 #
-#   runghc make_travis_yml_2.hs '--doctest' '--hlint' '-o' '.travis.yml' 'hackage-db.cabal'
+#   runghc make_travis_yml_2.hs '--doctest' '--hlint' '-o' '.travis.yml' 'hackage-db.cabal' '--no-unconstrained'
 #
 # For more information, see https://github.com/haskell-CI/haskell-ci
 #
 language: c
-sudo: false
 
 git:
   submodules: false  # whether to recursively clone submodules
@@ -28,9 +27,9 @@ before_cache:
 
 matrix:
   include:
-    - compiler: "ghc-8.6.2"
+    - compiler: "ghc-8.6.3"
     # env: TEST=--disable-tests BENCH=--disable-benchmarks
-      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.4,ghc-8.6.2], sources: [hvr-ghc]}}
+      addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.4,ghc-8.6.3], sources: [hvr-ghc]}}
     - compiler: "ghc-8.4.4"
     # env: TEST=--disable-tests BENCH=--disable-benchmarks
       addons: {apt: {packages: [ghc-ppa-tools,cabal-install-2.4,ghc-8.4.4], sources: [hvr-ghc]}}
@@ -75,9 +74,10 @@ install:
   - grep -Ev -- '^\s*--' ${HOME}/.cabal/config | grep -Ev '^\s*$'
   - (cd /tmp && echo '' | cabal new-repl -w ${HC} --build-dep fail)
   - if [ $HCNUMVER -ge 80000 ]; then cabal new-install -w ${HC} -j2 --symlink-bindir=$HOME/.local/bin doctest --constraint='doctest ==0.16.*'; fi
-  - if [ $HCNUMVER -eq 80602 ]; then cabal new-install -w ${HC} -j2 --symlink-bindir=$HOME/.local/bin hlint --constraint='hlint ==2.1.*'; fi
+  - if [ $HCNUMVER -eq 80603 ]; then cabal new-install -w ${HC} -j2 --symlink-bindir=$HOME/.local/bin hlint --constraint='hlint ==2.1.*'; fi
   - "printf 'packages: \".\"\\n' > cabal.project"
-  - "printf 'write-ghc-environment-files: always' >> cabal.project"
+  - "printf 'write-ghc-environment-files: always\\n' >> cabal.project"
+  - "printf 'package hackage-db\\n  flags: +install-examples\\n' >> cabal.project"
   - touch cabal.project.local
   - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- hackage-db | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
   - cat cabal.project || true
@@ -100,7 +100,8 @@ script:
   - cd ${DISTDIR} || false
   - find . -maxdepth 1 -name '*.tar.gz' -exec tar -xvf '{}' \;
   - "printf 'packages: hackage-db-*/*.cabal\\n' > cabal.project"
-  - "printf 'write-ghc-environment-files: always' >> cabal.project"
+  - "printf 'write-ghc-environment-files: always\\n' >> cabal.project"
+  - "printf 'package hackage-db\\n  flags: +install-examples\\n' >> cabal.project"
   - touch cabal.project.local
   - "if ! $NOINSTALLEDCONSTRAINTS; then for pkg in $($HCPKG list --simple-output); do echo $pkg  | grep -vw -- hackage-db | sed 's/^/constraints: /' | sed 's/-[^-]*$/ installed/' >> cabal.project.local; done; fi"
   - cat cabal.project || true
@@ -115,16 +116,13 @@ script:
   - if [ $HCNUMVER -ge 80000 ]; then (cd hackage-db-* && doctest  src); fi
 
   # hlint
-  - if [ $HCNUMVER -eq 80602 ]; then (cd hackage-db-* && hlint src); fi
+  - if [ $HCNUMVER -eq 80603 ]; then (cd hackage-db-* && hlint src); fi
 
   # cabal check
   - (cd hackage-db-* && cabal check)
 
   # haddock
   - if $HADDOCK; then cabal new-haddock -w ${HC} ${TEST} ${BENCH} all; else echo "Skipping haddock generation";fi
 
-  # Build without installed constraints for packages in global-db
-  - if $UNCONSTRAINED; then rm -f cabal.project.local; echo cabal new-build -w ${HC} --disable-tests --disable-benchmarks all; else echo "Not building without installed constraints"; fi
-
-# REGENDATA ["--doctest","--hlint","-o",".travis.yml","hackage-db.cabal"]
+# REGENDATA ["--doctest","--hlint","-o",".travis.yml","hackage-db.cabal","--no-unconstrained"]
 # EOF

hackage-db.cabal

@@ -11,7 +11,7 @@ synopsis:               Access cabal-install's Hackage database via Data.Map
 cabal-version:          >= 1.10
 build-type:             Simple
 tested-with:            GHC == 7.6.3, GHC == 7.8.4, GHC == 7.10.3, GHC == 8.0.2
-                      , GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.2
+                      , GHC == 8.2.2, GHC == 8.4.4, GHC == 8.6.3
 
 description:
   This library provides convenient access to the local copy of the Hackage