Add a PackageTest test for missing static files.

The test builds and installs a package dynamically only, then builds and
install a package statically that depends on that dynamic package.

This demonstrates how cabal-install can fail when it ignores which build
artifacts are provided by a package, e.g. static and/or dynamic files.  Recent
changes add to the InstalledPackageInfo record so that installed packages are
more explicit in what is available, so that cabal-install is better able to
know when it should rebuild from source, when installed packages were not built
from config flags to build the required artifacts.

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/cabal.out

@@ -0,0 +1,14 @@
+# cabal v2-configure
+# cabal v2-build
+Resolving dependencies...
+Build profile: -w ghc-<GHCVER> -O1
+In order, the following will be built:
+ - dynamic-1.0 (lib) (first run)
+Configuring library for dynamic-1.0..
+Preprocessing library for dynamic-1.0..
+Building library for dynamic-1.0..
+# cabal v2-sdist
+Wrote tarball sdist to <ROOT>/cabal.dist/dynamic-sdist-repo/dynamic-1.0.tar.gz
+# cabal v2-configure
+# depender depender
+Dynamic's number is 3.

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/cabal.test.hs

@@ -0,0 +1,230 @@
+import Test.Cabal.Prelude
+
+-- Build and install a package dynamically only, then build and install a
+-- package statically that depends on that dynamic package.  Old cabals are
+-- tempted to consider both the source package and the installed package
+-- (IPI) option with dynamic-only flags as valid, so they normally construct a
+-- build plan with this IPI option that results in a build error like the
+-- following:
+-- > [1 of 1] Compiling Main             ( Main.hs, ../setup.dist/work/depender/dist/build/depender/depender-tmp/Main.o )
+-- >
+-- > Main.hs:3:1: error:
+-- >     Could not find module `Dynamic'
+-- >     There are files missing in the `dynamic-1.0' package,
+-- >     try running 'ghc-pkg check'.
+-- >     Use -v (or `:set -v` in ghci) to see a list of the files searched for.
+-- >   |
+-- >   | import qualified Dynamic (number)
+-- >   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+--
+-- However, with ‘--require-artifacts’ rather than ‘--no-require-artifacts’,
+-- cabal will detect this error in advance and reject this particular IPI,
+-- leaving only building the source package as the only valid package option
+-- (I) we can choose as an assignment for the QPN (and any other valid IPIs if
+-- there were multiple pre-installed packages to choose from, including those
+-- with configure flags that work for us).
+
+import Data.Maybe (fromMaybe)  -- for ghcPkg1'
+import Data.Version
+import System.Directory
+import System.FilePath
+
+main = do
+    cabalTest $ do
+        -- TODO: Debug this failure on Windows.
+        skipIfWindows
+
+        withPackageDb $ do
+            -- If ghc-pkg is too old, cabal-install still works but has the
+            -- same bug which we fixed, and our test would fail.  Skip.
+            skipIfOldGhcPkg
+
+            -- Build a package with only dynamic build artifacts.
+            sdistRepoDir <- (</> "dynamic-sdist-repo") . testWorkDir <$> getTestEnv
+            installDynamic sdistRepoDir
+
+            -- TODO: Before building a package that depends on this, just
+            -- double check that we actually have an IPI in the same packageDB
+            -- that will be used so that cabal-install will see it and be tempted.
+
+            -- Build a package that requires static build artifacts.  Old
+            -- cabal-installs don't bother to check static and dynamic
+            -- configuration, so it'll probably produce a build plan that'll
+            -- fail as we described above.  With the build artifact checker,
+            -- our pre-installed IPI option we made earlier is detected to not
+            -- be a valid option in advance, so rather than producing a build
+            -- plan we know will fail, instead reject this particular option,
+            -- so that the moduler resolver cabal-install uses only picks the
+            -- only valid option left, which is to build from source.  (For our
+            -- test to work, we need the depender build to be aware of both the
+            -- pre-installed option and also the source package so that it can
+            -- rebuild from source with the correct flags, so that the
+            -- bug/enhancement scenario can be reproduced.)
+            installDepender sdistRepoDir
+
+-- Run ‘ghc-pkg field base pkg-vanilla-lib’ to test whether the ghc-pkg
+-- we are using is new enough to support the 5 new IPI fields in the ‘.conf’
+-- files.  If ghc-pkg is too old, then its Cabal-syntax dependency
+-- (cabal-install also uses Cabal-syntax for the IPI fields) will emit an
+-- ‘Unknown field’ warning if cabal-install tries to update or register an IPI
+-- with new fields, but it should otherwise work besides having full
+-- functionality of the artifact checker.
+skipIfOldGhcPkg :: TestM ()
+skipIfOldGhcPkg = do
+    control <- resultExitCode <$> ghcPkg1' "field" ["*", "id"]
+    hasArts <- resultExitCode <$> ghcPkg1' "field" ["*", "pkg-vanilla-lib"]
+
+    -- cabal-install will still work without these 5 build artifact fields,
+    -- except the artifact checker wouldn't detect missing artifacts
+    -- without knowing what artifacts installed packages provide.
+    skipIf "ghc-pkg too old for 5 arts fields" $ hasArts /= control
+
+-- ghcPkg' that can return non-zero.
+--
+-- It's basically a copy except without ‘requireSuccess’.
+ghcPkg1' :: String -> [String] -> TestM Result
+ghcPkg1' cmd args = do
+    env <- getTestEnv
+    unless (testHavePackageDb env) $
+        error "Must initialize package database using withPackageDb"
+    -- NB: testDBStack already has the local database
+    ghcConfProg <- requireProgramM ghcProgram
+    let db_stack = testPackageDBStack env
+        extraArgs = ghcPkgPackageDBParams
+                        (fromMaybe
+                            (error "ghc-pkg: cannot detect version")
+                            (programVersion ghcConfProg))
+                        db_stack
+    recordHeader ["ghc-pkg", cmd]
+    runProgram1M ghcPkgProgram (cmd : extraArgs ++ args) Nothing
+    where
+        runProgram1M :: Program -> [String] -> Maybe String -> TestM Result
+        runProgram1M prog args input = do
+            configured_prog <- requireProgramM prog
+            -- TODO: Consider also using other information from
+            -- ConfiguredProgram, e.g., env and args
+            run1M (programPath configured_prog) args input
+
+        run1M :: FilePath -> [String] -> Maybe String -> TestM Result
+        run1M path args input = do
+            env <- getTestEnv
+            r <- liftIO $ run (testVerbosity env)
+                        (Just (testCurrentDir env))
+                        (testEnvironment env)
+                        path
+                        args
+                        input
+            recordLog r
+            return r
+
+-- Flags.
+-- (Swap the line comments to trigger the bug the artifect checker validation
+-- step fixes - the ‘missing files’ error.)
+--commonArgs = ["--disable-backup", "--no-require-artifacts"]
+commonArgs = ["--disable-backup"]
+dynamicArgs =
+    [
+        "--enable-shared",
+        "--enable-executable-dynamic",
+        "--disable-library-vanilla",
+        "--disable-static",
+        "--disable-executable-static"
+    ]
+staticArgs =
+    [
+        "--enable-static"
+    ]
+
+-- Build a package with only dynamic build artifacts.
+installDynamic :: FilePath -> TestM ()
+installDynamic sdistRepoDir = do
+    withDirectory "dynamic" $ do
+        withSourceCopyDir ("dyn") $ do
+            cwd <- fmap testSourceCopyDir getTestEnv
+            -- (Now do ‘cd ..’, since withSourceCopyDir made our previous
+            -- previous such withDirectories now accumulate to be
+            -- relative to cabal.dist/dyn, not testSourceDir
+            -- (see 'testCurrentDir').)
+            withDirectory ".." $ do
+                -- Our project still resides in ‘dynamic/’.
+                withDirectory "dynamic" $ do
+                    cabal "v2-configure" $ [] ++ commonArgs ++ dynamicArgs
+                    cabal "v2-build" $ []
+                    recordMode DoNotRecord $ do
+                        cabal "v2-install" $ ["--lib"] ++ commonArgs ++ dynamicArgs
+                    tmpBuildDir <- (</> "dynamic-sdist-build") . testWorkDir <$> getTestEnv
+                    cabal "v2-sdist" $ ["-o", sdistRepoDir, "--builddir", tmpBuildDir]
+
+-- Build a package that requires static build artifacts.  (The same packageDB
+-- is shared.)
+installDepender :: FilePath -> TestM ()
+installDepender sdistRepoDir = do
+    withDirectory "depender" $ do
+        withSourceCopyDir ("depr") $ do
+            cwd <- fmap testSourceCopyDir getTestEnv
+            -- (As before.)
+            withDirectory ".." $ do
+                withDirectory "depender" $ do
+                    -- depender knows of the source package and the installed package.
+                    -- The installed package should only have dynamic files (.dyn_hi,
+                    -- .so), but not any static files (.a, .hi).  New ghc-pkg IPI file
+                    -- fields track these, so with a new GHC, a new cabal-install
+                    -- should reject the installed package while building the tree
+                    -- (reason: missing build artifacts) and instead choose the sdist
+                    -- (source package) so that it can figure out its own configuration
+                    -- flags.
+                    --
+                    -- (For instance, if you comment out the sdist references so that we
+                    -- only see the installed package, you should see an error message
+                    -- like this (e.g. remove those two ‘-- ’ strings to write out only
+                    -- a ‘packages: ./../dep…’ line):)
+                    -- > Error: cabal: Could not resolve dependencies:
+                    -- > [__0] trying: depender-1.0 (user goal)
+                    -- > [__1] next goal: dynamic (dependency of depender)
+                    -- > [__1] rejecting: dynamic-1.0/installed-19c7c1e50b8f1e56115c4f668dfdadd7114fc2c7dad267c2df43028892cc0ff5 (missing build artifacts: static artifacts)
+                    -- > [__1] fail (backjumping, conflict set: depender, dynamic)
+                    -- > After searching the rest of the dependency tree exhaustively, these were the goals I've had most trouble fulfilling: depender (3), dynamic (2)
+
+                    -- Setup the project file.
+                    -- > sed -nEe 's/\{SDIST\}/…path…to…sdist…dir…/g; p' < cabal.project.in > cabal.project
+                    writeSourceFile "cabal.project" . unlines $
+                        [
+                            "packages: ./../depender/*.cabal",
+                            -- "" {-
+                            "",
+                            "repository my-local-repository",
+                            "    url: file+noindex://" ++ sdistRepoDir ++ "#shared-cache"
+                            --    -}
+                        ]
+
+                    -- Make sure our test scenario setup lets the depender see
+                    -- the pre-installed dynamic package IPI we built.
+                    guessedPackageDbPath <- do
+                        recordMode DoNotRecord $ do
+                            guessPackageDbPathDepender
+                    let sharedPackageDbFlags = ["--package-db=" ++ guessedPackageDbPath]
+
+                    -- Use 'staticArgs' here.
+                    cabal "v2-configure" $ [] ++ commonArgs ++ staticArgs ++ sharedPackageDbFlags
+                    recordMode DoNotRecord $ do
+                        cabal "v2-build" $ [] ++ sharedPackageDbFlags
+
+                    -- Optional: check the output.
+                    recordMode DoNotRecord $ do
+                        cabal "v2-install" $ [] ++ commonArgs ++ staticArgs
+                    withPlan $ do
+                        runPlanExe' "depender" "depender" []
+                            >>= assertOutputContains "Dynamic's number is 3."
+
+guessPackageDbPathDepender :: TestM FilePath
+guessPackageDbPathDepender = do
+    env <- getTestEnv
+    hasGhc <- isAvailableProgram ghcProgram
+    skipUnless "failed to guess package-db: couldn't find ghc" hasGhc
+    tryProgramVersion <- programVersion <$> requireProgramM ghcProgram
+    let convertVersion = makeVersion . versionNumbers
+    programVersion <- maybe (skip "failed to guess package-db: unknown ghc version" >> return "") return $ showVersion . convertVersion <$> tryProgramVersion
+    path <- liftIO . canonicalizePath $ testCabalDir env </> "store" </> "ghc-" ++ programVersion </> "package.db"
+    exists <- liftIO $ doesPathExist path
+    skipUnless ("failed to guess package-db: guessed dir path does not exist: " ++ path) exists
+    return path

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/depender/depender/.gitignore

@@ -0,0 +1 @@
+/cabal.project

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/depender/depender/Main.hs

@@ -0,0 +1,7 @@
+module Main where
+
+import qualified Dynamic (number)
+
+main :: IO ()
+main = do
+    putStrLn $ "Dynamic's number is " ++ (show Dynamic.number) ++ "."

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/depender/depender/cabal.project.in

@@ -0,0 +1,4 @@
+packages: ./*.cabal
+
+repository my-local-repository
+    url: file+noindex://{SDIST_PATH}#shared-cache

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/depender/depender/depender.cabal

@@ -0,0 +1,9 @@
+cabal-version: >= 1.10
+name: depender
+version: 1.0
+build-type: Simple
+
+executable depender
+  build-depends: dynamic, base
+  default-language: Haskell2010
+  main-is: Main.hs

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/dynamic/dynamic/Dynamic.hs

@@ -0,0 +1,10 @@
+module Dynamic where
+
+simple :: (a -> b -> c) -> b -> a -> c
+simple f = \a b -> f b a
+
+name :: String
+name = "Dynamic"
+
+number :: Integer
+number = 3

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/dynamic/dynamic/cabal.project

@@ -0,0 +1 @@
+packages: ./*.cabal

cabal-testsuite/PackageTests/LinkerOptions/DynDeps/dynamic/dynamic/dynamic.cabal

@@ -0,0 +1,10 @@
+cabal-version: >= 1.10
+name: dynamic
+version: 1.0
+build-type: Simple
+
+library
+  default-language: Haskell2010
+  build-depends: base
+  exposed-modules:
+    Dynamic