Make mojo_binary / mojo_test compile action support path mapping

mojo/extensions.bzl

@@ -4,19 +4,13 @@ load("//mojo:mojo_host_platform.bzl", "mojo_host_platform")
 load("//mojo/private:mojo_gpu_toolchains_repository.bzl", "mojo_gpu_toolchains_repository")
 
 _PLATFORMS = ["linux_aarch64", "linux_x86_64", "macos_arm64"]
-_DEFAULT_VERSION = "1.0.0b2.dev2026060706"
+_DEFAULT_VERSION = "1.0.0b3.dev2026061206"
 _KNOWN_SHAS = {
-    "1.0.0b2.dev2026060706": {
-        "linux_aarch64": "ff57b49bb38eb832302a72d4f4c2f2c7553bf559ee5de2798daafb57a37877e8",
-        "linux_x86_64": "e28b4b663cce73416507f957b54d2b4c96a7bd3f42bbe41ec74e8c0b6f93444c",
-        "macos_arm64": "45261916bb30cfe16d2bd04bcfcf3ded8dca0934ec33b559316891a5217588e6",
-        "mojo_compiler_mojo_libs": "4452a8ad98634178c0cae20799a41e385a306159f94b409955ac95e052dd9e55",
-    },
-    "1.0.0b2.dev2026051806": {
-        "linux_aarch64": "224c4c1590debdff509bde74ead2da7b3eef2bc052380627e824072fe18bef05",
-        "linux_x86_64": "7775e0386cb564cfd09f34c74209b80fc5a5d43b5ac20e36e638032e0f0cd63a",
-        "macos_arm64": "5effdfe6fa9962802bba236baa15541584d7c27e3224d304d39d00912113fe58",
-        "mojo_compiler_mojo_libs": "63e7bcbca2f311d6aba0c90cdd3c1152d153ee3f0f65ccc5c4f06f61b84c06e4",
+    "1.0.0b3.dev2026061206": {
+        "linux_aarch64": "061042c815d945c8e403a13c5317d6dbd9ceef5a0ef84422ae6b6da0a2f0fe59",
+        "linux_x86_64": "b7f569472b02a35f40c8ea96ea51dac73b6c6c085e23c08ecf3613276df4f7dd",
+        "macos_arm64": "bc4106c6013994b4eb246702832c7bc6967c4f6eeaa911eccf75d2dff26d7a3a",
+        "mojo_compiler_mojo_libs": "1c99770a8a14804f810e6a2a12f1fd5b8d5c783301b38b74c785bc421ac334b9",
     },
 }
 _PLATFORM_MAPPINGS = {

mojo/private/mojo_binary_test.bzl

@@ -90,6 +90,12 @@ def _find_main(name, srcs, main):
 
     fail("Multiple Mojo files provided, but no main file specified. Please set 'main = \"foo.mojo\"' to disambiguate.")
 
+def _format_include(arg):
+    return ["-I", arg.dirname]
+
+def _format_path(arg):
+    return [arg.path]
+
 def _mojo_binary_test_implementation(ctx, *, shared_library = False):
     cc_toolchain = find_cpp_toolchain(ctx)
     mojo_toolchain = ctx.exec_groups["mojo_compile"].toolchains["//:toolchain_type"].mojo_toolchain_info
@@ -103,18 +109,19 @@ def _mojo_binary_test_implementation(ctx, *, shared_library = False):
     args.add("build")
     args.add("-strip-file-prefix=.")
     args.add("--emit", "object")
-    args.add("-o", object_file.path)
+    args.add("-o", object_file)
+    args.add("--lld-path", mojo_toolchain.lld)
 
     main = _find_main(ctx.label.name, ctx.files.srcs, ctx.file.main)
-    args.add(main.path)
+    args.add(main)
     root_directory = main.dirname
     for file in ctx.files.srcs:
         if not file.dirname.startswith(root_directory):
-            args.add("-I", file.dirname)
+            args.add_all([file], map_each = _format_include)
 
     all_deps = ctx.attr.deps + mojo_toolchain.implicit_deps + ([ctx.attr._link_extra_lib] if ctx.attr._link_extra_lib else [])
-    import_paths, transitive_mojodeps = collect_mojoinfo(all_deps)
-    args.add_all(import_paths, before_each = "-I")
+    _, transitive_mojodeps = collect_mojoinfo(all_deps)
+    args.add_all(transitive_mojodeps, map_each = _format_include)
 
     # NOTE: Argument order:
     # 1. Basic functional arguments
@@ -154,13 +161,16 @@ def _mojo_binary_test_implementation(ctx, *, shared_library = False):
             "MODULAR_CRASH_REPORTING_ENABLED": "false",
             "MODULAR_MOJO_MAX_COMPILERRT_PATH": "/dev/null",  # Make sure this fails if accessed
             "MODULAR_MOJO_MAX_LINKER_DRIVER": "/dev/null",  # Make sure this fails if accessed
-            "MODULAR_MOJO_MAX_LLD_PATH": mojo_toolchain.lld.path,
+            "MODULAR_MOJO_MAX_LLD_PATH": "/dev/null",  # Make sure this fails if accessed
             "PATH": "/dev/null",  # Avoid using the host's PATH
             "TEST_TMPDIR": ".",
         } | build_env,
         use_default_shell_env = True,
         exec_group = "mojo_compile",
         toolchain = "//:toolchain_type",
+        execution_requirements = {
+            "supports-path-mapping": "1",
+        },
     )
 
     feature_configuration = cc_common.configure_features(

tests/shared_library.mojo

@@ -1,3 +1,3 @@
 @export
-def foo() -> Int:
+def foo() abi("C") -> Int:
     return 42