[#108] Add coarse_nix and stack_nix to the build matrix (not working:…

… "no space left on device")

re: "Prelude.read no parse" error that RRN reported:

`nix-shell` sets an environment variable, SIZE=size. I've not been
able track down what specific package is responsible for this. I tried
to write another minimal shell.nix script and that shell had this
environment variable too.

Gibbon tries to parse "size" as an Int (in Gibbon.Common.getRunConfig)
and that doesn't work out very well. Until we figure out the source of
this rogue variable, we *unset* it run_all_tests.sh.

Now, Travis fails with "No space left on device" while trying to
install Gibbon's dependencies (the Haskell ones, via Stack) :(

.travis.yml

@@ -1,15 +1,16 @@
-# To set the default GCC version to 7
 sudo: required
 
-# Do not choose a language; we provide our own build tools.
-language: generic
-# language: nix
+# Install some Nix tools.
+# See https://docs.travis-ci.com/user/languages/nix.
+language: nix
 
-# Caching so the next build will be fast too.
 cache:
   directories:
   - $HOME/.stack
 
+# TODO: after the Nix jobs start working on Travis we should look into
+# caching Nix things too: https://nixos.wiki/wiki/Nix_on_Travis.
+
 # Ensure necessary system libraries are present
 addons:
   apt:
@@ -23,21 +24,38 @@ addons:
       - ghc-8.4.3
 
 # Build in three modes, varying ONLY the environment used to build
-# Docker code 
-env:
-  - 
-  - STACK_DOCKER=1
-#  - STACK_NIX=1
-
-# Temporary:
+# Docker code.
 matrix:
+  include:
+    - name: Default
+
+    - name: stack_docker
+      env: STACK_DOCKER=1
+
+    # Travis fails with "No space left on device" while trying to install
+    # Gibbon's dependencies (the Haskell ones, via Stack) :(
+    - name: coarse_nix
+      env: COARSE_NIX=1
+      install: skip
+      addons: skip
+      script:
+        - df -h
+        - nix-shell shell.nix --run "COARSE_NIX=1 ./run_all_tests.sh"
+
+    - name: stack_nix
+      env: STACK_NIX=1
+
+  # Temporary:
   allow_failures:
-    - env: STACK_DOCKER=1
-#    - env: STACK_NIX=1
-
+    - name: stack_docker
+    - name: coarse_nix
+    - name: stack_nix
+
 install:
   # Download and unpack the stack executable
   # The Ubuntu package is only available on >16.04. Travis is using 14.04.
+  # Update: Travis supports Ubuntu 16.04 since Nov 2018. We should start
+  # using that.
   - echo "Installing Stack...\n"
   - mkdir -p ~/.local/bin
   - export PATH=$HOME/.local/bin:$PATH
@@ -66,6 +84,7 @@ install:
 git:
   submodules: false
 
+# Default.
 script:
   ./run_all_tests.sh
 

gibbon-compiler/stack.yaml

@@ -5,7 +5,6 @@ packages:
 
 extra-deps:
 - s-cargot-0.1.4.0
-- haskell-src-exts-simple-1.20.0.0
 
 flags: {}
 extra-package-dbs: []
@@ -16,20 +15,13 @@ extra-package-dbs: []
 # If you want to pin things for reproducible builds
 nix:
   enable: false
-  packages: [gcc, which]
+  # packages: [gcc, which]
   # path: ["https://github.com/NixOS/nixpkgs-channels/archive/nixos-17.03.tar.gz"]
   # nixos-unstable snapshot:
   # path: ["nixpkgs=https://github.com/NixOS/nixpkgs-channels/archive/1e1472ed93e1256dfdac4908ae8edcb90ceff21c.tar.gz"]
-  # shell-file: shell.nix
+  shell-file: shell.nix
   path: ["nixpkgs=https://github.com/NixOS/nixpkgs-channels/archive/nixos-18.09.tar.gz"]
 
-# [2018.05.23] (chai):
-# Ugh, Stack fails to construct a build plan with my system GHC, even though it's pinned to 8.2.2,
-# which is the same version that it expects. It tries to build deepseq-1.4.4.0 which is not even released yet.
-# Pinning a particular version of deepseq leads to further errors. Disabling this for now.
-#
-# system-ghc: true
-
 docker:
   enable: false
   auto-pull: true

run_all_tests.sh

@@ -120,6 +120,7 @@ echo "  Gibbon Compiler (1/2): build & unit tests"
 echo "-------------------------------------------"
 set -x
 cd $top/gibbon-compiler
+df -h
 
 if [ "$LLVM_ENABLED" == "1" ]; then
     echo "Building Gibbon with LLVM enabled"
@@ -134,6 +135,18 @@ echo "--------------------------------------------"
 # Turning off -j for now [2016.11.06]
 cd $top/gibbon-compiler
 # make answers
+
+## CSK: nix-shell sets an environment variable, SIZE=size. I've not been able
+## track down what specific package is responsible for this. I tried to write
+## another minimal shell.nix script and that shell had this environment
+## variable too.
+##
+## This leads to the "Prelude.read no parse" error that RRN reported in #108.
+## Gibbon tries to parse "size" as an Int (in Gibbon.Common.getRunConfig) and
+## that doesn't work out very well. Until we figure out the source of this
+## rogue variable, we *unset* it here.
+unset SIZE ITERS
+
 $STK exec test-gibbon-examples -- -v2