From cc379b60f0af632aeb8c4e0f42820a03d90d673a Mon Sep 17 00:00:00 2001
From: Ilan Joselevich <personal@ilanjoselevich.com>
Date: Mon, 24 Jun 2024 21:13:50 +0300
Subject: [PATCH] tests.buildRustCrate: add crateLibOutputsWasm32

Added a cross compilation test for wasm32-unknown-unknown. This also
required using crate.metadata instead of using the regex to get rid of
the hash in the library filename. It also required adding a mkCrate
argument to assertOutputs so we can override the buildRustCrate used.
---
 .../rust/build-rust-crate/test/default.nix    | 33 +++++++++++++++----
 1 file changed, 27 insertions(+), 6 deletions(-)

diff --git a/pkgs/build-support/rust/build-rust-crate/test/default.nix b/pkgs/build-support/rust/build-rust-crate/test/default.nix
index 522eedfede7f..f2b238280521 100644
--- a/pkgs/build-support/rust/build-rust-crate/test/default.nix
+++ b/pkgs/build-support/rust/build-rust-crate/test/default.nix
@@ -8,6 +8,7 @@
 , stdenv
 , symlinkJoin
 , writeTextFile
+, pkgsCross
 }:
 
 let
@@ -120,7 +121,10 @@ let
 
        `name` is used as part of the derivation name that performs the checking.
 
-       `crateArgs` is passed to `mkHostCrate` to build the crate with `buildRustCrate`.
+       `mkCrate` can be used to override the `mkCrate` call/implementation to use to
+       override the `buildRustCrate`, useful for cross compilation. Uses `mkHostCrate` by default.
+
+       `crateArgs` is passed to `mkCrate` to build the crate with `buildRustCrate`
 
        `expectedFiles` contains a list of expected file paths in the output. E.g.
        `[ "./bin/my_binary" ]`.
@@ -129,13 +133,13 @@ let
        output is used but e.g. `output = "lib";` will cause the lib output
        to be checked instead. You do not need to specify any directories.
      */
-    assertOutputs = { name, crateArgs, expectedFiles, output? null }:
+    assertOutputs = { name, mkCrate ? mkHostCrate, crateArgs, expectedFiles, output? null, }:
       assert (builtins.isString name);
       assert (builtins.isAttrs crateArgs);
       assert (builtins.isList expectedFiles);
 
       let
-        crate = mkHostCrate (builtins.removeAttrs crateArgs ["expectedTestOutput"]);
+        crate = mkCrate (builtins.removeAttrs crateArgs ["expectedTestOutput"]);
         crateOutput = if output == null then crate else crate."${output}";
         expectedFilesFile = writeTextFile {
           name = "expected-files-${name}";
@@ -155,7 +159,7 @@ let
       ''
       # sed out the hash because it differs per platform
       + ''
-        | sed -E -e 's/-[0-9a-fA-F]{10}\.rlib/-HASH.rlib/g' \
+        | sed 's/-${crate.metadata}//g' \
         > "$actualFiles"
       diff -q ${expectedFilesFile} "$actualFiles" > /dev/null || {
         echo -e "\033[0;1;31mERROR: Difference in expected output files in ${crateOutput} \033[0m" >&2
@@ -604,7 +608,7 @@ let
       };
       expectedFiles = [
         "./nix-support/propagated-build-inputs"
-        "./lib/libtest_lib-HASH.rlib"
+        "./lib/libtest_lib.rlib"
         "./lib/link"
       ];
     };
@@ -621,7 +625,24 @@ let
       };
       expectedFiles = [
         "./nix-support/propagated-build-inputs"
-        "./lib/libtest_lib-HASH.rlib"
+        "./lib/libtest_lib.rlib"
+        "./lib/link"
+      ];
+    };
+
+    crateLibOutputsWasm32 = assertOutputs {
+      name = "wasm32-crate-lib";
+      output = "lib";
+      mkCrate = mkCrate pkgsCross.wasm32-unknown-none.buildRustCrate;
+      crateArgs = {
+        libName = "test_lib";
+        type = [ "cdylib" ];
+        libPath = "src/lib.rs";
+        src = mkLib "src/lib.rs";
+      };
+      expectedFiles = [
+        "./nix-support/propagated-build-inputs"
+        "./lib/test_lib.wasm"
         "./lib/link"
       ];
     };