Add Nix support to language tests

.github/workflows/ci.yaml

@@ -527,6 +527,9 @@ jobs:
           elixir-version: "1.16.1"
           rebar3-version: "3"
 
+      - name: Install Nix
+        uses: nixbuild/nix-quick-install-action@v27
+
       - name: Download Glistix binary from previous job
         uses: actions/download-artifact@v4
         with:
@@ -557,6 +560,10 @@ jobs:
         run: make clean bun
         working-directory: ./test/language
 
+      - name: test/language Nix
+        run: make clean nix
+        working-directory: ./test/language
+
       - name: test/compile_package0
         run: make
         working-directory: ./test/compile_package0

test/language/Makefile

@@ -24,3 +24,8 @@ deno:
 bun:
 	@echo test/languate on JavaScript with Bun
 	cargo run --quiet -- test --target javascript --runtime bun
+
+.phony: nix
+nix:
+	@echo test/language on Nix
+	cargo run --quiet -- test --target nix

test/language/test/ffi.gleam

@@ -2,24 +2,30 @@ pub type Dynamic
 
 @external(erlang, "ffi_erlang", "print")
 @external(javascript, "./ffi_javascript.mjs", "print")
+@external(nix, "./ffi_nix.nix", "print")
 pub fn print(a: String) -> Nil
 
 @external(erlang, "ffi_erlang", "append")
 @external(javascript, "./ffi_javascript.mjs", "append")
+@external(nix, "./ffi_nix.nix", "append")
 pub fn append(a: String, b: String) -> String
 
 @external(erlang, "ffi_erlang", "to_string")
 @external(javascript, "./ffi_javascript.mjs", "toString")
+@external(nix, "./ffi_nix.nix", "toString")
 pub fn to_string(a: anything) -> String
 
 @external(erlang, "ffi_erlang", "file_exists")
 @external(javascript, "./ffi_javascript.mjs", "fileExists")
+@external(nix, "./ffi_nix.nix", "fileExists")
 pub fn file_exists(a: String) -> Bool
 
 @external(erlang, "ffi_erlang", "halt")
 @external(javascript, "./ffi_javascript.mjs", "halt")
+@external(nix, "./ffi_nix.nix", "halt")
 pub fn halt(a: Int) -> Nil
 
 @external(erlang, "ffi_erlang", "to_dynamic")
 @external(javascript, "./ffi_javascript.mjs", "toDynamic")
+@external(nix, "./ffi_nix.nix", "toDynamic")
 pub fn to_dynamic(a: x) -> Dynamic

test/language/test/ffi_nix.nix

@@ -0,0 +1,15 @@
+let
+  print = msg: builtins.trace msg null;
+  append = a: b: a + b;
+  toString = builtins.toJSON;
+  fileExists =
+    f:
+        let
+            # ./. is relative to this file in the build directory (language/build/dev/nix/ffi_nix.nix)
+            # In other targets, this would be relative to 'language/', so let's go back there
+            absPath = if builtins.isString f && builtins.substring 0 1 f != "/" then ./../../../../${f} else f;
+        in builtins.pathExists absPath;
+  halt = code: if code == 0 then null else builtins.abort (toString code);
+  toDynamic = x: x;
+in
+{ inherit print append toString fileExists halt toDynamic; }

test/language/test/importable.gleam

@@ -16,6 +16,7 @@ pub const ints_in_bit_array = <<1, 2, 3>>
 
 pub const string_in_bit_array = <<"Gleam":utf8>>
 
+@target(erlang)
 pub const data = <<
   0x1,
   2,
@@ -26,6 +27,41 @@ pub const data = <<
   <<<<1, 2, 3>>:bits, "Gleam":utf8, 1024>>:bits,
 >>
 
+@target(javascript)
+pub const data = <<
+  0x1,
+  2,
+  2:size(16),
+  0x4:size(32),
+  "Gleam":utf8,
+  4.2:float,
+  <<<<1, 2, 3>>:bits, "Gleam":utf8, 1024>>:bits,
+>>
+
+@target(nix)
+pub const data = <<
+  0x1,
+  2,
+  2:size(16),
+  0x4:size(32),
+  "Gleam":utf8,
+  <<<<1, 2, 3>>:bits, "Gleam":utf8, 1024>>:bits,
+>>
+
+@target(erlang)
+pub fn get_bit_array() {
+  <<
+    0x1,
+    2,
+    2:size(16),
+    0x4:size(32),
+    "Gleam":utf8,
+    4.2:float,
+    <<<<1, 2, 3>>:bits, "Gleam":utf8, 1024>>:bits,
+  >>
+}
+
+@target(javascript)
 pub fn get_bit_array() {
   <<
     0x1,
@@ -38,6 +74,19 @@ pub fn get_bit_array() {
   >>
 }
 
+// TODO: impl :float on nix
+@target(nix)
+pub fn get_bit_array() {
+  <<
+    0x1,
+    2,
+    2:size(16),
+    0x4:size(32),
+    "Gleam":utf8,
+    <<<<1, 2, 3>>:bits, "Gleam":utf8, 1024>>:bits,
+  >>
+}
+
 pub const language = "gleam"
 
 pub type Movie {