SetupHooks: add tests

This adds tests for error messages related to SetupHooks:

  - error when returning an invalid component diff in a
    per-component pre-configure hook
  - error when declaring pre-build rules whose dependency
    graph contains cycles
  - error when we cannot find a dependency of a pre-build rule
  - warning when there are pre-build rules that are declared but
    never demanded

It also adds some correctness tests for SetupHooks, e.g. that
pre-build rules are run in dependency order (see the
`SetupHooksRuleOrdering` test).

Author: sheaf

Cabal-tests/tests/UnitTests/Distribution/Utils/Structured.hs

@@ -33,15 +33,15 @@ md5Check proxy md5Int = structureHash proxy @?= md5FromInteger md5Int
 md5CheckGenericPackageDescription :: Proxy GenericPackageDescription -> Assertion
 md5CheckGenericPackageDescription proxy = md5Check proxy
 #if MIN_VERSION_base(4,19,0)
-    0x5a48c6570cbcf96af4c51f38962e37b5
+    0x03b0282cd561d1b1563d16fa061e3dd7
 #else
-    0xc5c0e54b95e651216e92db04c9cd4ecf
+    0x00633b73694ed591f0437e54905b5b61
 #endif
 
 md5CheckLocalBuildInfo :: Proxy LocalBuildInfo -> Assertion
 md5CheckLocalBuildInfo proxy = md5Check proxy
 #if MIN_VERSION_base(4,19,0)
-    0x92782413689aba84f1ae8a71e0ff4475
+    0x6f6302c2aea249e02c17ae5a047eef9f
 #else
-    0xfa44477c60b169f306656c4df793c2c5
+    0x3032ed4480d707e373e2e627e580e7ae
 #endif

cabal-testsuite/PackageTests/SetupHooksBadDiff1/Setup.hs

@@ -0,0 +1,7 @@
+module Main where
+
+import Distribution.Simple ( defaultMainWithSetupHooks )
+import SetupHooks ( setupHooks )
+
+main :: IO ()
+main = defaultMainWithSetupHooks setupHooks

cabal-testsuite/PackageTests/SetupHooksBadDiff1/SetupHooks.hs

@@ -0,0 +1,18 @@
+module SetupHooks where
+
+import Distribution.Simple.SetupHooks
+
+import Control.Monad ( void )
+
+setupHooks :: SetupHooks
+setupHooks =
+  noSetupHooks
+    { configureHooks =
+        noConfigureHooks
+          { preConfComponentHook = Just pccHook }
+    }
+
+pccHook :: PreConfComponentHook
+pccHook _ = return $
+  PreConfComponentOutputs $ ComponentDiff $ CExe emptyExecutable
+    -- Bad: component is a library, but we returned an executable!

cabal-testsuite/PackageTests/SetupHooksBadDiff1/cabal.project

@@ -0,0 +1 @@
+packages: .

cabal-testsuite/PackageTests/SetupHooksBadDiff1/setup-hooks-bad-diff1-test.cabal

@@ -0,0 +1,16 @@
+cabal-version:       3.12
+name:                setup-hooks-bad-diff1-test
+version:             0.1.0.0
+synopsis:            Test 1 for a bad component diff
+license:             BSD-3-Clause
+author:              NA
+maintainer:          NA
+category:            Testing
+build-type:          Hooks
+
+custom-setup
+  setup-depends: Cabal-hooks, base
+
+library
+  build-depends:       base
+  default-language:    Haskell2010

cabal-testsuite/PackageTests/SetupHooksBadDiff1/setup.out

@@ -0,0 +1,5 @@
+# Setup configure
+Configuring setup-hooks-bad-diff1-test-0.1.0.0...
+Error: [Cabal-9491]
+Hooks: mismatched component types in per-component configure hook.
+Trying to apply an executable diff to a library.

cabal-testsuite/PackageTests/SetupHooksBadDiff1/setup.test.hs

@@ -0,0 +1,3 @@
+import Test.Cabal.Prelude
+main = setupTest $ do
+  fails $ setup "configure" []

cabal-testsuite/PackageTests/SetupHooksBadDiff2/Setup.hs

@@ -0,0 +1,7 @@
+module Main where
+
+import Distribution.Simple ( defaultMainWithSetupHooks )
+import SetupHooks ( setupHooks )
+
+main :: IO ()
+main = defaultMainWithSetupHooks setupHooks

cabal-testsuite/PackageTests/SetupHooksBadDiff2/SetupHooks.hs

@@ -0,0 +1,27 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module SetupHooks where
+
+import Distribution.Simple.SetupHooks
+
+import Control.Monad ( void )
+
+setupHooks :: SetupHooks
+setupHooks =
+  noSetupHooks
+    { configureHooks =
+        noConfigureHooks
+          { preConfComponentHook = Just pccHook }
+    }
+
+pccHook :: PreConfComponentHook
+pccHook _ = return $
+  -- Make invalid changes to a library
+  PreConfComponentOutputs $ ComponentDiff $ CLib $
+    emptyLibrary
+      { libName = LSubLibName "hocus-pocus"
+      , libExposed = False
+      , libBuildInfo =
+          emptyBuildInfo
+            { buildable = False }
+      }

cabal-testsuite/PackageTests/SetupHooksBadDiff2/cabal.project

@@ -0,0 +1 @@
+packages: .