[ new ] Support for dumping a package's install location (idris-lang#…

…3381)

* qol improvements to buildIdris function

* remove env var export that does not have an impact on install process

* Add support for asking the compiler where it will install a package

* allow buildIdris to find C libs installed per Pack standard practice

* Add changelog entry

* add test that exercises new installdir command

* support testing on windows

CHANGELOG_NEXT.md

@@ -21,6 +21,10 @@ This CHANGELOG describes the merged but unreleased changes. Please see [CHANGELO
 * The `idris2 --init` command now ensures that package names are
   valid Idris2 identifiers.
 
+* A new `idris2 --dump-installdir {ipkg-filename}` command outputs the file path
+  where Idris2 will install the given package if `idris2 --install
+  {ipkg-filename}` is called.
+
 ### Building/Packaging changes
 
 * The Nix flake's `buildIdris` function now returns a set with `executable` and

nix/buildIdris.nix

@@ -50,7 +50,7 @@ let
       nativeBuildInputs = [ idris2 makeWrapper jq ] ++ attrs.nativeBuildInputs or [];
       buildInputs = propagatedIdrisLibraries ++ attrs.buildInputs or [];
 
-      IDRIS2_PACKAGE_PATH = libDirs;
+      env.IDRIS2_PACKAGE_PATH = libDirs;
 
       buildPhase = ''
         runHook preBuild
@@ -60,10 +60,10 @@ let
 
       passthru = {
         inherit propagatedIdrisLibraries;
-      };
+      } // (attrs.passthru or {});
 
       shellHook = ''
-        export IDRIS2_PACKAGE_PATH="${finalAttrs.IDRIS2_PACKAGE_PATH}"
+        export IDRIS2_PACKAGE_PATH="${finalAttrs.env.IDRIS2_PACKAGE_PATH}"
       '';
     }
   );
@@ -112,6 +112,13 @@ in rec {
         mkdir -p $out/${libSuffix}
         export IDRIS2_PREFIX=$out/lib
         idris2 ${installCmd} ${ipkgFileName}
+        # check if the package has installed any C libs to ./lib
+        # (a practice popularized by the Pack package manager)
+        for file in ./lib/*{.so,.dylib,.h}; do
+          installDir="$(idris2 --dump-installdir "${ipkgFileName}")/lib"
+          mkdir -p "$installDir"
+          mv -- "$file" "$installDir"/
+        done
         runHook postInstall
       '';
     };

src/Idris/CommandLine.idr

@@ -25,6 +25,7 @@ data PkgCommand
       | REPL
       | Init
       | DumpJson
+      | DumpInstallDir
 
 export
 Show PkgCommand where
@@ -37,6 +38,7 @@ Show PkgCommand where
   show REPL = "--repl"
   show Init = "--init"
   show DumpJson = "--dump-ipkg-json"
+  show DumpInstallDir = "--dump-installdir"
 
 public export
 data DirCommand
@@ -284,6 +286,9 @@ options = [MkOpt ["--check", "-c"] [] [CheckOnly]
            MkOpt ["--dump-ipkg-json"] [Optional "package file"]
               (\ f => [Package DumpJson f])
               (Just "Dump an Idris2 package file in the JSON format"),
+           MkOpt ["--dump-installdir"] [Optional "package file"]
+              (\ f => [Package DumpInstallDir f])
+              (Just "Dump the location where the given package will be installed"),
            MkOpt ["--build"] [Optional "package file"]
                (\f => [Package Build f])
               (Just "Build modules/executable for the given package"),

src/Idris/Package.idr

@@ -604,6 +604,12 @@ installSrcFrom wdir destdir (ns, srcRelPath)
            | Left err => throw $ UserError (show err)
          pure ()
 
+absoluteInstallDir : (relativeInstallDir : String) -> Core String
+absoluteInstallDir relativeInstallDir = do
+  mdestdir <- coreLift $ getEnv "DESTDIR"
+  let destdir = fromMaybe "" mdestdir
+  pure $ destdir ++ relativeInstallDir
+
 -- Install all the built modules in prefix/package/
 -- We've already built and checked for success, so if any don't exist that's
 -- an internal error.
@@ -617,11 +623,9 @@ install pkg opts installSrc -- not used but might be in the future
     = do defs <- get Ctxt
          build <- ttcBuildDirectory
          let lib = installDir pkg
-         mdestdir <- coreLift $ getEnv "DESTDIR"
-         let destdir = fromMaybe "" mdestdir
-         libTargetDir <- (destdir ++) <$> libInstallDirectory lib
-         ttcTargetDir <- (destdir ++) <$> ttcInstallDirectory lib
-         srcTargetDir <- (destdir ++) <$> srcInstallDirectory lib
+         libTargetDir <- absoluteInstallDir =<< libInstallDirectory lib
+         ttcTargetDir <- absoluteInstallDir =<< ttcInstallDirectory lib
+         srcTargetDir <- absoluteInstallDir =<< srcInstallDirectory lib
 
          let src = source_dir (dirs (options defs))
          runScript (preinstall pkg)
@@ -959,6 +963,10 @@ processPackage opts (cmd, mfile)
                     runRepl (map snd $ mainmod pkg)
                   Init => pure () -- already handled earlier
                   DumpJson => coreLift . putStrLn $ toJson pkg
+                  DumpInstallDir => do
+                    libInstallDir <- libInstallDirectory (installDir pkg)
+                    dir <- absoluteInstallDir libInstallDir
+                    coreLift (putStrLn dir)
 
 record PackageOpts where
   constructor MkPFR

tests/idris2/pkg/pkg020/expected

@@ -0,0 +1,2 @@
+/idris2-0.7.0/test-0.3.0
+/idris2-0.7.0

tests/idris2/pkg/pkg020/run

@@ -0,0 +1,14 @@
+. ../../../testutils.sh
+
+windows_tweaks() {
+  sed 's#C:.msys64##' | sed 's#\\#/#g'
+}
+
+# pretend Idris2 is installed at root for reproducible
+# installdirs:
+IDRIS2_PREFIX=/ idris2 --dump-installdir test.ipkg \
+  | windows_tweaks
+
+# by contrast, the location containing all installed packages:
+IDRIS2_PREFIX=/ idris2 --libdir \
+  | windows_tweaks

tests/idris2/pkg/pkg020/src/Stuff.idr

@@ -0,0 +1,5 @@
+module Stuff
+
+export
+say : String
+say = "Stuff"

tests/idris2/pkg/pkg020/test.ipkg

@@ -0,0 +1,8 @@
+package test
+version = 0.3.0
+
+-- modules to install
+modules = Stuff
+
+sourcedir = "src"
+