Factor out travis-haskell-env; install deps when needed.

It's too much of a pain to have the entire travis build script be in
"eval", so I've factored that part out, meaning we need 2 lines instead
of 1 in each repo's "script" section (1 for executing the script, 1 for
eval env).

We now build libsodium and c-toxcore if needed by the package.

Author: iphydf

Diff for: .travis.yml

@@ -26,7 +26,7 @@ script:
 deploy:
   provider: releases
   token:
-    secure: "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"
+    secure: "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"
   file: hs-tools-$TRAVIS_TAG.tar.gz
   skip_cleanup: true
   on:

Diff for: bin/travis-haskell

@@ -0,0 +1,95 @@
+#!/bin/bash
+
+set -eu
+
+# Determine the Haskell package we're building.
+PACKAGE=$(echo "$TRAVIS_REPO_SLUG" | sed -e 's|^[^/]*/hs-||')
+  
+# Usage: bash <(curl -s https://raw.githubusercontent.com/TokTok/hs-tools/master/bin/travis-haskell) script
+travis-script() {
+  # Install the latest CI support tools.
+  VERSION=$(curl -L -s -H 'Accept: application/json' \
+    "https://github.com/TokTok/hs-tools/releases/latest" \
+    | egrep -o '"v[0-9][^"]+"' \
+    | egrep -o '[^"]+')
+  TOOLS_URL="https://github.com/Toktok/hs-tools/releases/download/$VERSION/hs-tools-$VERSION.tar.gz"
+  curl -L -s "$TOOLS_URL" | tar xz -C "$HOME"
+  
+  # Where to find libraries.
+  export LD_LIBRARY_PATH=$HOME/.local/lib
+  export PKG_CONFIG_PATH=$HOME/.local/lib/pkgconfig
+  
+  NEED_SODIUM=$(stack ls dependencies --test | grep saltine > /dev/null && echo 1)
+  NEED_TOXCORE=$(grep 'extra-libraries:.*toxcore' *.cabal > /dev/null && echo 1)
+  
+  if [ -n "$NEED_SODIUM" ]; then
+    NEED_TOXCORE=1
+  fi
+  
+  # libsodium
+  if [ "$NEED_SODIUM" == 1 -a ! -f $HOME/.local/lib/libsodium.so ]; then
+    git clone --depth=1 --branch=stable https://github.com/jedisct1/libsodium
+    cd libsodium
+    ./configure --prefix=$HOME/.local
+    make install -j$(nproc)
+  fi
+  
+  # c-toxcore
+  if [ "$NEED_SODIUM" == 1 -a ! -f $HOME/.local/lib/libtoxcore.so ]; then
+    git clone --depth=1 https://github.com/TokTok/c-toxcore
+    cd c-toxcore
+    cmake -B_build -H. -DCMAKE_INSTALL_PREFIX:PATH=$HOME/.local \
+      -DBUILD_TOXAV=OFF \
+      -DBOOTSTRAP_DAEMON=OFF \
+      -DAUTOTEST=OFF \
+      -DDHT_BOOTSTRAP=OFF
+    make -C_build install -j$(nproc)
+  fi
+  
+  # Run the build/test/deploy (optional) cycle.
+  hlint .
+  stylish-haskell-lhs -i .
+  git diff --exit-code
+  stack --no-terminal test --coverage \
+    --extra-include-dirs=$HOME/.local/include \
+    --extra-lib-dirs=$HOME/.local/lib
+  shc "$PACKAGE" testsuite
+  stack sdist --tar-dir .
+}
+
+# Usage: eval $(travis-haskell env)
+travis-env() {
+  # Check that the tag we're building and trying to release agrees with the
+  # version number in Cabal.
+  if [ -n "$TRAVIS_TAG" ]; then
+    VERSION="${TRAVIS_TAG/v/}"
+    if [ ! -f "$PACKAGE-$VERSION.tar.gz" ]; then
+      echo 'echo "Package versions or name mismatch"'
+      echo 'ls'
+      echo 'exit 1'
+      exit 1
+    fi
+  else
+    VERSION=""
+  fi
+  
+  # Export variables here to make them available in the deploy step.
+  cat <<EOF
+export PACKAGE="$PACKAGE"
+export VERSION="$VERSION"
+EOF
+}
+
+# Usage: travis-haskell deploy
+travis-deploy() {
+  # No "set -x" here, because we don't want to print the username/password on the
+  # Travis console.
+  set +x
+  
+  mkdir -p "$HOME/.stack/upload"
+  echo "{\"username\":\"$HACKAGE_USERNAME\",\"password\":\"$HACKAGE_PASSWORD\"}" \
+    > "$HOME/.stack/upload/credentials.json"
+  stack --no-terminal upload .
+}
+
+travis-$1