Reorganize tests

Use `rule_test` to verify that a rule a) worked, b) produced the
expected output. This obviates the need for a shell script that
launches binaries and is more general, so can be used systematically.
It's the testing strategy that `rules_rust` uses. We may want to
revive launching binaries later, but this is good enough for now.
Also, systematically put each test in its own subdir.

haskell/haskell.bzl

@@ -112,7 +112,7 @@ _haskell_common_attrs = {
     doc="Package/binary version"
   ),
   "ghcVersion": attr.string(
-    default="8.0.2",
+    default="8.2.2",
     # TODO (fuuzetsu): We need this because we have to generate
     # correct suffix for shared libraries that GHC expects for
     # dynamic-library-dirs content. As currently we're using GHC from

tests/BUILD

@@ -5,67 +5,49 @@ load("@io_tweag_rules_haskell//haskell:haskell.bzl",
      "haskell_library",
 )
 
-haskell_binary(
-    name = "hello",
-    srcs = ["Main.hs"],
-    deps = ["//tests/test-lib"]
-)
+load("@bazel_tools//tools/build_rules:test_rules.bzl", "rule_test")
 
-haskell_binary(
-  name = "two-libs-one-BUILD",
-  main = "TogetherTest.main",
-  srcs = ["TogetherTest.hs"],
-  deps = [
-    "//tests/together-lib:one",
-    "//tests/together-lib:two"
-  ]
+rule_test(
+  name = "test-binary-simple",
+  generates = ["binary-simple"],
+  rule = "//tests/binary-simple",
+  size = "small",
 )
 
-haskell_binary(
-  name = "non-top-srcs",
-  sourceDir = "non-top-srcs",
-  srcs = [
-    "non-top-srcs/Test.hs",
-    "non-top-srcs/Main.hs"
-  ],
-  prebuilt_dependencies = ["base"]
+rule_test(
+  name = "test-binary-with-lib",
+  generates = ["binary-with-lib"],
+  rule = "//tests/binary-with-lib",
+  size = "small",
 )
 
-haskell_binary(
-  name = "main-is",
-  main = "MainIs.mainIs",
-  srcs = [ "MainIs.hs" ],
-  prebuilt_dependencies = ["base"],
+rule_test(
+  name = "test-binary-with-prebuilt",
+  generates = ["binary-with-prebuilt"],
+  rule = "//tests/binary-with-prebuilt",
+  size = "small",
 )
 
-
-haskell_library(
-  name = "hsc-lib",
-  sourceDir = "hsc",
-  srcs = [],
-  hscs = ["hsc/Test.hsc"],
-  prebuilt_dependencies = ["base"]
+rule_test(
+  name = "test-binary-with-main",
+  generates = ["binary-with-main"],
+  rule = "//tests/binary-with-main",
+  size = "small",
 )
 
-# https://github.com/tweag/rules_haskell/issues/13
-haskell_binary(
-  name = "hsc",
-  sourceDir = "hsc",
-  srcs = ["hsc/Main.hs"],
-  prebuilt_dependencies = ["base"],
-  deps = [":hsc-lib"],
+rule_test(
+  name = "test-library-deps",
+  generates =
+    ["library-deps-1.0.0/library-deps-1.0.0.conf",
+     "library-deps-1.0.0/package.cache",
+    ],
+  rule = "//tests/library-deps",
+  size = "small",
 )
 
-[sh_test(
-    name = "Run" + binary,
-    srcs = ["test_binary.sh"],
-    args = ["$(location %s)" % binary],
-    data = [":%s" % binary],
-    timeout="short",
-) for binary in [
-    "hello",
-    "two-libs-one-BUILD",
-    "non-top-srcs",
-    "main-is",
-    "hsc",
-]]
+rule_test(
+  name = "test-hsc",
+  generates = ["hsc"],
+  rule = "//tests/hsc",
+  size = "small",
+)

tests/binary-simple/BUILD

@@ -0,0 +1,9 @@
+load("@io_tweag_rules_haskell//haskell:haskell.bzl",
+  "haskell_binary",
+)
+
+haskell_binary(
+  name = "binary-simple",
+  srcs = ["Main.hs"],
+  visibility = ["//visibility:public"]
+)

tests/binary-simple/Main.hs

@@ -0,0 +1,3 @@
+module Main where
+
+main = return ()

tests/binary-with-lib/BUILD

@@ -0,0 +1,17 @@
+load("@io_tweag_rules_haskell//haskell:haskell.bzl",
+  "haskell_binary",
+  "haskell_library",
+)
+
+haskell_library(
+  name = "lib",
+  srcs = glob(["src/*.hs"]),
+  sourceDir = "src",
+)
+
+haskell_binary(
+  name = "binary-with-lib",
+  srcs = ["Main.hs"],
+  deps = ["lib"],
+  visibility = ["//visibility:public"],
+)

tests/binary-with-lib/Main.hs

@@ -0,0 +1,5 @@
+module Main where
+
+import Lib (value)
+
+main = print value

tests/binary-with-lib/src/Lib.hs

@@ -0,0 +1,5 @@
+{-# LANGUAGE NoImplicitPrelude #-}
+
+module Lib (value) where
+
+value = 42

tests/binary-with-main/BUILD

@@ -0,0 +1,10 @@
+load("@io_tweag_rules_haskell//haskell:haskell.bzl",
+  "haskell_binary",
+)
+
+haskell_binary(
+  name = "binary-with-main",
+  srcs = ["MainIsHere.hs"],
+  main = "MainIsHere.this",
+  visibility = ["//visibility:public"]
+)

tests/binary-with-main/MainIsHere.hs

@@ -0,0 +1,4 @@
+module MainIsHere (this) where
+
+this :: IO ()
+this = return ()

tests/binary-with-prebuilt/BUILD

@@ -0,0 +1,10 @@
+load("@io_tweag_rules_haskell//haskell:haskell.bzl",
+  "haskell_binary",
+)
+
+haskell_binary(
+  name = "binary-with-prebuilt",
+  srcs = ["Main.hs"],
+  prebuilt_dependencies = ["base", "template-haskell"],
+  visibility = ["//visibility:public"]
+)

tests/binary-with-prebuilt/Main.hs

@@ -0,0 +1,6 @@
+module Main where
+
+import Data.List ()
+import Language.Haskell.TH ()
+
+main = return ()

tests/hsc/BUILD

@@ -0,0 +1,20 @@
+load(
+  "@io_tweag_rules_haskell//haskell:haskell.bzl",
+  "haskell_library",
+  "haskell_binary",
+)
+
+haskell_library(
+  name = "hsc-lib",
+  hscs = ["Test.hsc"],
+  prebuilt_dependencies = ["base"],
+)
+
+# https://github.com/tweag/rules_haskell/issues/13
+haskell_binary(
+  name = "hsc",
+  srcs = ["Main.hs"],
+  prebuilt_dependencies = ["base"],
+  deps = [":hsc-lib"],
+  visibility = ["//visibility:public"],
+)

tests/library-deps/BUILD

@@ -0,0 +1,12 @@
+load(
+  "@io_tweag_rules_haskell//haskell:haskell.bzl",
+  "haskell_library",
+)
+
+haskell_library(
+  name = "library-deps",
+  srcs = ["TestLib.hs"],
+  deps = ["//tests/library-deps/sublib"],
+  prebuilt_dependencies = ["base"],
+  visibility = ["//visibility:public"],
+)

tests/library-deps/sublib/BUILD

@@ -0,0 +1,11 @@
+load(
+  "@io_tweag_rules_haskell//haskell:haskell.bzl",
+  "haskell_library",
+)
+
+haskell_library(
+  name = "sublib",
+  srcs = ["TestSubLib.hs"],
+  prebuilt_dependencies = ["base"],
+  visibility = ["//visibility:public"],
+)

tests/together-lib/BUILD → tests/two-libs/BUILD

@@ -3,6 +3,16 @@ package(default_visibility = ["//visibility:public"])
 load(
   "@io_tweag_rules_haskell//haskell:haskell.bzl",
   "haskell_library",
+  "haskell_binary",
+)
+
+haskell_binary(
+  name = "two-libs",
+  srcs = ["Main.hs"],
+  deps = [
+    "one",
+    "two"
+  ]
 )
 
 haskell_library(

tests/TogetherTest.hs → tests/two-libs/Main.hs

@@ -1,4 +1,4 @@
-module TogetherTest (main) where
+module Main where
 
 import One (one)
 import Two (two)