arguments to test binaries

see: https://doc.rust-lang.org/cargo/commands/cargo-test.html : two dashes + https://doc.rust-lang.org/rustc/tests/index.html

packages/rust/src/executors/test/schema.json

@@ -140,6 +140,12 @@
       "type": "boolean",
       "default": false,
       "description": "Build all test targets"
+    },
+    "-- --test-threads": {
+      "type": "number",
+      "minimum": 0,
+      "default": 0,
+      "description": "arguments following the two dashes (--) are passed to the test binaries, 0 disables option"
     }
   },
   "required": []

packages/rust/src/utils/build-command.ts

@@ -14,10 +14,21 @@ export function buildCommand(
 
   args.push(baseCommand);
 
+  // flags after '-- ' should be passed to binaries after any other option
+  let argstobinaries = ['--'];
   for (const [key, value] of Object.entries(options)) {
     if (key === 'toolchain') {
       continue;
     }
+    if (key === '-- --test-threads' && value === 0) {
+      // -- --test-threads=0 comes from schema default to avoid setting thread number if not rquested
+      continue;
+    }
+    if (key.startsWith('-- ') ) {
+      // use '-- ' only once, save argument to append to the end of args
+      argstobinaries.push(key.substring(3), value);
+      continue;
+    }
 
     if (typeof value === 'boolean') {
       // false flags should not be added to the cargo args
@@ -36,6 +47,9 @@ export function buildCommand(
   if (!args.includes("--package")) {
     args.push("-p", context.projectName);
   }
+  if (argstobinaries.length > 1) {
+    args.push(...argstobinaries);
+  }
 
   return args;
 }