Add Bash script for starting development

HACKING.md

@@ -21,6 +21,13 @@ list, which is a good place to ask questions.
 
 [Cabal/tests/README.md]: Cabal/tests/README.md
 
+Setting up on a Unix-like system
+--------------------------------
+
+The instructions below have been compiled into a Bash script which can
+do the setup in a fully automated fashion. See the file `setup-dev.sh`
+in the root directory of this Git repository.
+
 Building Cabal from git cloned sources and running the tests
 ------------------------------------------------------------
 

setup-dev.sh

+#!/bin/bash -x
+SCRIPT_DIR="`dirname $0`"
+
+die() {
+    echo "$*"
+    exit 1
+}
+
+build_and_test() {
+   # Find sandbox location
+   local PACKAGEDB=`cabal exec -- sh -c 'echo $GHC_PACKAGE_PATH' | sed 's/:.*//'`
+   echo "Cabal package DB location: $PACKAGEDB"
+   # Do the building
+  ./Setup configure --enable-tests --package-db="$PACKAGEDB" || die "$1 'configure' failed"
+  ./Setup build || die "$1 'build' failed"
+# Disabled for now: Tests fail on my system for some reason
+#  ./Setup test || die "$1 'test' failed"
+}
+
+install_deps() {
+   cabal install --only-dependencies --enable-tests || die "$1: Could not install needed dependencies"
+}
+
+create_setup() {
+   ghc --make -threaded Setup.hs || die "$1: Could not create 'Setup' executable"
+}
+
+init_sandbox() {
+   cabal sandbox delete # Ignore error status; probably just means sandbox doesn't exist
+   cabal sandbox init || die "$1: Could not initialize sandbox"
+}
+
+setup_cabal() {
+   init_sandbox Cabal
+   install_deps Cabal
+   create_setup Cabal
+   build_and_test Cabal
+}
+
+setup_cabalinstall() {
+   init_sandbox cabal-install
+   cabal sandbox add-source ../Cabal/ || die "cabal-install: Failed to add ../Cabal source"
+   install_deps cabal-install
+   create_setup cabal-install
+   build_and_test cabal-install
+}
+
+# Build
+(cd ${SCRIPT_DIR}/Cabal         && setup_cabal       ) || die "Failed to build Cabal"
+(cd ${SCRIPT_DIR}/cabal-install && setup_cabalinstall) || die "Failed to build cabal-install"