Add GHCi test suite

bin/snack

@@ -62,9 +62,6 @@ if [[ -z "$COMMAND" ]]; then
   exit 1
 fi
 
-echo "snack nix: $SNACK_NIX"
-echo "command: $COMMAND"
-
 case $COMMAND in
   build)
     "$NIX_BUILD" --no-out-link -A build "$SNACK_NIX"
@@ -75,7 +72,6 @@ case $COMMAND in
     ;;
   run)
     res=$("$NIX_BUILD" --no-out-link -A build "$SNACK_NIX")
-    echo "running $res"
     "$res/out"
     ;;
 esac

default.nix

@@ -8,4 +8,3 @@
       ["NIX_BUILD=${pkgs.nix}/bin/nix-build"]
       (builtins.readFile ./bin/snack));
 }
-

script/test

@@ -11,9 +11,28 @@ set -euo pipefail
 ## Functions
 
 banner() {
+    echo
     echo "--- $*"
 }
 
+capture_io() {
+    OUT_FILE="$1"
+
+    cat <<END_HEREDOC
+import GHC.IO.Handle
+import System.IO
+old_stdout <- hDuplicate stdout
+:{
+withFile "$OUT_FILE" WriteMode $ \\h -> do
+    hDuplicateTo h stdout
+    $2
+    hDuplicateTo old_stdout stdout
+:}
+END_HEREDOC
+}
+
+export -f capture_io
+
 fail() {
   echo "ERROR: $*"
   exit 1
@@ -25,22 +44,22 @@ cd "$(dirname "$0")/.."
 
 banner "Test packages"
 pushd tests/packages
-snack build
+./test
 popd
 
 banner "Test Template Haskell"
 pushd tests/template-haskell
-snack build
+./test
 popd
 
 banner "Test Template Haskell 2"
 pushd tests/template-haskell-2
-snack build -f code/snack.nix
+./test
 popd
 
 banner "Test Template Haskell 3"
 pushd tests/template-haskell-3
-snack build
+./test
 popd
 
 banner "Test stack-exe formatting"

shell.nix

@@ -0,0 +1,7 @@
+{ pkgs ? import ./nix {} }:
+let
+  snack = (pkgs.callPackage ./. {}).snack-exe;
+in pkgs.mkShell
+  { name = "snack-shell";
+    buildInputs = [ snack ];
+  }

tests/packages/expected

@@ -0,0 +1,6 @@
+1
+2
+3
+4
+5
+Leaving GHCi.

tests/packages/golden

@@ -0,0 +1,5 @@
+1
+2
+3
+4
+5

tests/packages/test

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+# vim: ft=sh sw=2 et
+
+set -euo pipefail
+
+snack build
+snack run | diff golden -
+
+TMP_FILE=$(mktemp)
+
+capture_io "$TMP_FILE" main | snack ghci
+
+diff golden $TMP_FILE
+rm $TMP_FILE

tests/template-haskell-2/golden

@@ -0,0 +1,2 @@
+Hello, World!
+

tests/template-haskell-2/test

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+# vim: ft=sh sw=2 et
+
+set -euo pipefail
+
+snack build -f code/snack.nix
+snack run -f code/snack.nix | diff golden -
+
+TMP_FILE=$(mktemp)
+
+capture_io "$TMP_FILE" main | snack -f code/snack.nix ghci
+
+diff golden $TMP_FILE
+rm $TMP_FILE

tests/template-haskell-3/golden

@@ -0,0 +1,2 @@
+Hello, World!
+

tests/template-haskell-3/test

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+# vim: ft=sh sw=2 et
+
+set -euo pipefail
+
+snack build
+snack run | diff golden -
+
+TMP_FILE=$(mktemp)
+
+capture_io "$TMP_FILE" main | snack ghci
+
+diff golden $TMP_FILE
+rm $TMP_FILE

tests/template-haskell/golden

@@ -0,0 +1,2 @@
+Hello, World!
+

tests/template-haskell/test

@@ -0,0 +1,14 @@
+#!/usr/bin/env bash
+# vim: ft=sh sw=2 et
+
+set -euo pipefail
+
+snack build
+snack run | diff golden -
+
+TMP_FILE=$(mktemp)
+
+capture_io "$TMP_FILE" main | snack ghci
+
+diff golden $TMP_FILE
+rm $TMP_FILE