Separate the compile stage from testing

Might be overkill for this small of a workflow.
Good to get practice with circleci and Make.

.circleci/config.yml

@@ -1,5 +1,30 @@
 version: 2
 jobs:
+  compile:
+    docker:
+      - image: haskell:8.2.2
+    steps:
+      - checkout
+      - restore_cache:
+          keys:
+            - v1-stack-{{ checksum "package.yaml" }}-{{ checksum "stack.yaml" }}
+            - v1-stack-{{ checksum "package.yaml" }}-
+            - v1-stack-
+          name: Restoring stack cache
+      - run:
+          name: Compile
+          command: make build
+      - presist_to_workspace:
+          root: dist
+          paths:
+            - '*'
+      - save_cache:
+          key: v1-stack-{{ checksum "package.yaml" }}-{{ checksum "stack.yaml" }}
+          name: Caching stack
+          paths:
+            - .stack-work
+            - /root/.stack
+
   sdist:
     docker:
       - image: haskell:8.2.2
@@ -20,25 +45,18 @@ jobs:
       - image: haskell:8.2.2
     steps:
       - checkout
-      - restore_cache:
-          keys:
-            - v1-stack-{{ checksum "package.yaml" }}-{{ checksum "stack.yaml" }}
-            - v1-stack-{{ checksum "package.yaml" }}-
-            - v1-stack-
-          name: Restoring stack cache
+      - attach_workspace:
+          at: dist
       - run:
           name: Test
           command: make test
-      - save_cache:
-          key: v1-stack-{{ checksum "package.yaml" }}-{{ checksum "stack.yaml" }}
-          name: Caching stack
-          paths:
-            - .stack-work
-            - /root/.stack
 
 workflows:
   version: 2
   base:
     jobs:
+      - compile
       - sdist
-      - test
+      - test:
+          requires:
+            - compile

Makefile

@@ -8,14 +8,31 @@ STACK_WORK ?= .stack-work
 VERBOSITY ?= warn
 
 CABAL_FILE := $(PROJECT_NAME).cabal
+DOC_TEST := $(DIST)/build/doc-test/doc-test
 GHCID := $(BIN)/ghcid
 STACK_FLAGS := --verbosity $(VERBOSITY)
 
-.DEFAULT_GOAL := build
+.DEFAULT_GOAL := $(EMPTY)/build
 
 $(BIN) $(DIST) $(EMPTY):
 	mkdir -p $@
 
+$(CABAL_FILE): package.yaml
+	# `stack` has no way to run `hpack` directly.
+	# We can run `hpack` indirectly with little overhead.
+	$(STACK) $(STACK_FLAGS) build --dry-run
+
+$(DOC_TEST): $(EMPTY)/build golden/**/*.json
+	$@
+
+$(EMPTY)/build: $(EMPTY)/stack-setup README.md Setup.hs package.yaml stack.yaml src/**/*.hs test/**/*.hs | $(DIST)
+	$(STACK) $(STACK_FLAGS) build --no-run-tests --test
+	cp -R $$($(STACK) $(STACK_FLAGS) path --dist-dir)/build $(DIST)/build
+	touch $@
+
+$(EMPTY)/doc-test: $(EMPTY)/build
+	touch $@
+
 $(EMPTY)/stack-setup: | $(EMPTY)
 	$(STACK) $(STACK_FLAGS) setup
 	touch $@
@@ -23,15 +40,6 @@ $(EMPTY)/stack-setup: | $(EMPTY)
 $(GHCID): $(EMPTY)/stack-setup | $(BIN)
 	$(STACK) $(STACK_FLAGS) install ghcid --local-bin-path $(BIN)
 
-$(CABAL_FILE): package.yaml
-	# `stack` has no way to run `hpack` directly.
-	# We can run `hpack` indirectly with little overhead.
-	$(STACK) $(STACK_FLAGS) build --dry-run
-
-.PHONY: build
-build: $(EMPTY)/stack-setup
-	$(STACK) $(STACK_FLAGS) build --no-run-tests --test
-
 .PHONY: cabal-check
 cabal-check: $(CABAL_FILE)
 	$(CABAL) check
@@ -49,8 +57,7 @@ sdist: cabal-check | $(DIST)
 	$(CABAL) sdist
 
 .PHONY: test
-test: build
-	$(STACK) $(STACK_FLAGS) test
+test: $(DOC_TEST)
 
 .PHONY: upload-hackage
 upload-hackage: sdist