#!/usr/bin/env fuchsia-vendored-python
# Copyright 2022 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Tests for rustc_remote_wrapper."""

import contextlib
import io
import os
import subprocess
import sys
import tempfile
import unittest

from pathlib import Path
from unittest import mock

import rustc_remote_wrapper
import rustc
import cl_utils
import fuchsia
import remote_action

from typing import Any, Iterable, Sequence


class ImmediateExit(Exception):
    """For mocking functions that do not return."""

    pass


def _write_file_contents(path: Path, contents: str):
    with open(path, "w") as f:
        f.write(contents)


def _read_file_contents(path: Path) -> str:
    with open(path, "r") as f:
        return f.read()


def _strs(items: Sequence[Any]) -> Sequence[str]:
    return [str(i) for i in items]


def _paths(items: Sequence[Any]) -> Sequence[Path]:
    if isinstance(items, list):
        return [Path(i) for i in items]
    elif isinstance(items, set):
        return {Path(i) for i in items}
    elif isinstance(items, tuple):
        return tuple(Path(i) for i in items)

    t = type(items)
    raise TypeError(f"Unhandled sequence type: {t}")


class AccompanyRlibWithSoTests(unittest.TestCase):
    def test_not_rlib(self):
        deps = Path("../path/to/foo.rs")
        self.assertEqual(
            list(rustc_remote_wrapper.accompany_rlib_with_so([deps])), [deps]
        )

    def test_rlib_without_so(self):
        deps = Path("obj/build/foo.rlib")
        with mock.patch.object(
            Path, "is_file", return_value=False
        ) as mock_isfile:
            self.assertEqual(
                list(rustc_remote_wrapper.accompany_rlib_with_so([deps])),
                [deps],
            )
        mock_isfile.assert_called_once()

    def test_rlib_with_so(self):
        deps = Path("obj/build/foo.rlib")
        with mock.patch.object(
            Path, "is_file", return_value=True
        ) as mock_isfile:
            self.assertEqual(
                list(rustc_remote_wrapper.accompany_rlib_with_so([deps])),
                [deps, Path("obj/build/foo.so")],
            )
            mock_isfile.assert_called_once()


class ExpandDepsForRlibCompileTests(unittest.TestCase):
    def test_proc_macro(self):
        deps = list(
            rustc_remote_wrapper.expand_deps_for_rlib_compile(
                [Path("foo/barmac.so")]
            )
        )
        self.assertEqual(deps, [Path("foo/barmac.so")])

    def test_rlib(self):
        deps = list(
            rustc_remote_wrapper.expand_deps_for_rlib_compile(
                [Path("foo/bar.rlib")]
            )
        )
        self.assertEqual(deps, [Path("foo/bar.rlib")])

    def test_rmeta_missing_rlib(self):
        deps = list(
            rustc_remote_wrapper.expand_deps_for_rlib_compile(
                [Path("foo/bar.rmeta")]
            )
        )
        self.assertEqual(deps, [Path("foo/bar.rmeta")])

    def test_rmeta_with_coexisting_rlib(self):
        with mock.patch.object(
            Path, "exists", return_value=True
        ) as mock_rlib_exists:
            deps = list(
                rustc_remote_wrapper.expand_deps_for_rlib_compile(
                    [Path("foo/bar.rmeta")]
                )
            )
        mock_rlib_exists.assert_called_once_with()
        self.assertEqual(deps, [Path("foo/bar.rmeta"), Path("foo/bar.rlib")])


class RustRemoteActionPrepareTests(unittest.TestCase):
    def generate_prepare_mocks(
        self,
        depfile_contents: Sequence[str] = None,
        compiler_shlibs: Sequence[Path] = None,
        clang_rt_libdir: Path = None,
        libcxx_static: Path = None,
    ) -> Iterable[mock.patch.object]:
        """common mocks needed for RustRemoteAction.prepare()"""
        # depfile only command
        yield mock.patch.object(
            rustc_remote_wrapper, "_make_local_depfile", return_value=0
        )

        if depfile_contents:
            yield mock.patch.object(
                rustc_remote_wrapper,
                "_readlines_from_file",
                return_value=[line + "\n" for line in depfile_contents],
            )

        # check compiler is executable
        yield mock.patch.object(
            rustc_remote_wrapper, "_tool_is_executable", return_value=True
        )

        if compiler_shlibs:
            yield mock.patch.object(
                rustc_remote_wrapper.RustRemoteAction,
                "_remote_rustc_shlibs",
                return_value=iter(compiler_shlibs),
            )

        yield mock.patch.object(
            rustc_remote_wrapper, "_libcxx_isfile", return_value=True
        )

        if clang_rt_libdir:
            yield mock.patch.object(
                fuchsia, "clang_runtime_libdirs", return_value=[clang_rt_libdir]
            )

        if libcxx_static:
            yield mock.patch.object(
                fuchsia, "clang_libcxx_static", return_value=libcxx_static or ""
            )

        # expected to be called through _rust_stdlib_libunwind_inputs()
        # when --sysroot is unspecified.
        yield mock.patch.object(
            rustc.RustAction,
            "default_rust_sysroot",
            return_value=Path("../some/random/sysroot"),
        )

    def test_prepare_basic(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs([compiler, source, "-o", rlib])
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        self.assertIsNone(r.clang_cxx_stdlibdir)
        dep_command, aux_rspfiles = r.dep_only_command_with_rspfiles
        (
            internal_dep_command,
            internal_aux_rspfiles,
        ) = r._rust_action.dep_only_command_with_rspfiles(r.local_depfile)
        self.assertEqual(dep_command, internal_dep_command)
        self.assertEqual(aux_rspfiles, internal_aux_rspfiles)
        self.assertEqual(aux_rspfiles, [])

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps)
        )
        self.assertEqual(remote_output_files, {rlib})

    def test_cxx_stdlibdir(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs([compiler, source, "-o", rlib])
        cxx_libdir = Path("../tools/clang/find/libcxx/here")
        r = rustc_remote_wrapper.RustRemoteAction(
            [f"--cxx-stdlibdir={cxx_libdir}", "--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        self.assertEqual(r.clang_cxx_stdlibdir, cxx_libdir)

    def test_prepare_with_rmeta_file_in_scanned_deps(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        rmeta_dep = Path("obj/bar.rmeta")
        implied_rlib_dep = Path("obj/bar.rlib")
        deps = [rmeta_dep]
        depfile_contents = [str(d) + ":" for d in deps]

        with tempfile.TemporaryDirectory() as td:
            tdp = Path(td)
            command = _strs([compiler, source, "-o", rlib])
            r = rustc_remote_wrapper.RustRemoteAction(
                ["--"] + command,
                exec_root=exec_root,
                working_dir=working_dir,
                auto_reproxy=False,
            )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            # 'expand_rmetas' checks for file existence
            # specificially co-existence of .rlib with .rmeta
            with mock.patch.object(
                Path, "exists", return_value=True
            ) as mock_rlib_exists:
                prepare_status = r.prepare()

            mock_rlib_exists.assert_called()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        # The corresponding .rlib from the .rmeta dep is considered a remote input.
        self.assertEqual(
            remote_inputs,
            set([compiler, shlib_rel, source, implied_rlib_dep] + deps),
        )
        self.assertEqual(remote_output_files, {rlib})

    def test_prepare_with_response_file(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]

        with tempfile.TemporaryDirectory() as td:
            tdp = Path(td)
            rsp = tdp / "foo.rsp"
            rsp.write_text(
                "\n".join(_strs(["# expand these args", source, "-o", rlib]))
                + "\n"
            )
            command = _strs(
                [compiler, f"@{rsp}"]
            )  # pass args through response file
            r = rustc_remote_wrapper.RustRemoteAction(
                ["--"] + command,
                exec_root=exec_root,
                working_dir=working_dir,
                auto_reproxy=False,
            )

            mocks = self.generate_prepare_mocks(
                depfile_contents=depfile_contents,
                compiler_shlibs=[shlib_rel],
            )
            with contextlib.ExitStack() as stack:
                for m in mocks:
                    stack.enter_context(m)
                prepare_status = r.prepare()

            self.assertEqual(prepare_status, 0)  # success

            # Expect there was a temporary response file written next to the
            # original one, also inside the temporary dir.
            # It should be marked for cleanup.
            self.assertTrue(
                any(str(f).startswith(str(rsp)) for f in r._cleanup_files)
            )

        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source, rsp] + deps)
        )
        self.assertEqual(remote_output_files, {rlib})

    def test_dep_only_command_filtered(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_path = Path("obj/foo.rlib.d")
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs(
            [
                compiler,
                source,
                "--local-only=--foo=bar",
                "-o",
                rlib,
                f"--emit=dep-info={depfile_path}",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )
        dep_command, _ = r.dep_only_command_with_rspfiles
        self.assertIn("--foo=bar", dep_command)
        self.assertNotIn("--local-only=--foo=bar", dep_command)

    def test_prepare_depfile(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_path = Path("obj/foo.rlib.d")
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs(
            [compiler, source, "-o", rlib, f"--emit=dep-info={depfile_path}"]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps)
        )
        self.assertEqual(remote_output_files, {rlib, depfile_path})
        self.assertFalse(a.skipping_some_download)
        # Even if download_outputs=false, the depfile is required locally.
        self.assertEqual(set(a.expected_downloads), remote_output_files)

    def test_prepare_depfile_download_false(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_path = Path("obj/foo.rlib.d")
        depfile_contents = [str(d) + ":" for d in deps]
        # skip downloading the main output
        command = _strs(
            [
                compiler,
                source,
                "-o",
                rlib,
                f"--emit=dep-info={depfile_path}",
                "--remote-flag=--download_outputs=false",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps)
        )
        self.assertEqual(remote_output_files, {rlib, depfile_path})
        self.assertTrue(a.skipping_some_download)
        # Even if download_outputs=false, the depfile is required locally.
        self.assertEqual(set(a.expected_downloads), {depfile_path})

    def test_prepare_depfile_failure(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        depfile_path = Path("obj/foo.rlib.d")
        # mocking failure, no need for actual depfile contents
        command = _strs(
            [compiler, source, "-o", rlib, f"--emit=dep-info={depfile_path}"]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        # Make sure internal RuntimeError gets handled.
        with mock.patch.object(
            rustc_remote_wrapper, "_make_local_depfile", return_value=1
        ) as mock_deps:
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 1)  # failure

    def test_prepare_llvm_ir(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        llvm_ir = Path("obj/foo.ll")
        deps = [Path("../foo/src/other.rs")]
        depfile_path = Path("obj/foo.rlib.d")
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs([compiler, source, "-o", rlib, f"--emit=llvm-ir"])
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps)
        )
        # Even if download_outputs=false, we want the non-primary outputs.
        self.assertEqual(remote_output_files, {rlib, llvm_ir})
        self.assertFalse(a.skipping_some_download)
        self.assertEqual(set(a.expected_downloads), remote_output_files)

    def test_prepare_llvm_ir_download_false(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        llvm_ir = Path("obj/foo.ll")
        deps = [Path("../foo/src/other.rs")]
        depfile_path = Path("obj/foo.rlib.d")
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs(
            [
                compiler,
                source,
                "-o",
                rlib,
                f"--emit=llvm-ir",
                "--remote-flag=--download_outputs=false",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps)
        )
        # Even if download_outputs=false, we want the non-primary outputs.
        self.assertEqual(remote_output_files, {rlib, llvm_ir})
        self.assertTrue(a.skipping_some_download)
        self.assertEqual(set(a.expected_downloads), {llvm_ir})

    def test_prepare_externs(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        externs = _paths(
            [
                "obj/path/to/this.rlib",
                "obj/path/to/that.rlib",
            ]
        )
        extern_flags = [
            "--extern",
            f"this={externs[0]}",
            "--extern",
            f"that={externs[1]}",
        ]
        command = _strs([compiler, source, "-o", rlib]) + extern_flags
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps + externs)
        )
        self.assertEqual(remote_output_files, {rlib})

    def test_prepare_link_arg_files(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        link_arg = Path("obj/some/random.a")
        command = _strs(
            [compiler, source, "-o", rlib, f"-Clink-arg={link_arg}"]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs,
            set([compiler, shlib_rel, source] + deps + [link_arg]),
        )
        self.assertEqual(remote_output_files, {rlib})

    def test_prepare_needs_linker(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        exec_root_rel = cl_utils.relpath(exec_root, start=working_dir)
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        linker = Path("../tools/bin/linker")
        lld = Path("../tools/bin/ld.lld")
        clang_rt_libdir = Path("../fake/lib/clang/x86_64-unknown-linux")
        libcxx = Path("fake/clang/libc++.a")
        source = Path("../foo/src/lib.rs")
        target = "x86_64-unknown-linux-gnu"
        exe = Path("obj/foo.exe")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs(
            [
                compiler,
                source,
                "-o",
                exe,
                "--crate-type",
                "bin",
                f"-Clinker={linker}",
                f"--target={target}",
                f"-Clink-arg=-fuse-ld=lld",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )
        self.assertEqual(r.linker, linker)
        self.assertEqual(r.remote_ld_path, lld)

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
            clang_rt_libdir=clang_rt_libdir,
            libcxx_static=exec_root_rel / libcxx,
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs,
            set(
                _paths(
                    [compiler, shlib_rel, source]
                    + deps
                    + [linker, lld, clang_rt_libdir, exec_root_rel / libcxx]
                )
            ),
        )
        self.assertEqual(remote_output_files, {exe})

    def test_prepare_remote_option_forwarding(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        remote_flag = "--some_forwarded_rewrapper_flag=value"  # not real
        command = _strs(
            [compiler, source, "-o", rlib, f"--remote-flag={remote_flag}"]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps)
        )
        self.assertEqual(remote_output_files, {rlib})
        # Position matters, not just presence.
        # Could override the set of standard options.
        self.assertEqual(r.remote_options[-1], remote_flag)

    def test_prepare_environment_names_input_file(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        env_file = Path("../path/to/config.json")
        command = _strs(
            [
                f"CONFIGURE_THINGY={env_file}",
                compiler,
                source,
                "-o",
                rlib,
                f"--remote-inputs={env_file}",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            # We are not scanning the environment variables automatically.
            # Users should follow the above example command and
            # explicitly pass --remote-inputs.
            with mock.patch.object(
                rustc_remote_wrapper, "_env_file_exists", return_value=True
            ) as mock_exists:
                prepare_status = r.prepare()
            mock_exists.assert_not_called()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs,
            set(_paths([compiler, shlib_rel, source, env_file] + deps)),
        )
        self.assertEqual(remote_output_files, {rlib})

    def test_native_compile(self):
        host_platform = fuchsia.REMOTE_PLATFORM
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path(f"../tools/{host_platform}/bin/rustc")
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        command = _strs([compiler, source, "-o", rlib])
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            host_platform=host_platform,
            auto_reproxy=False,
        )
        self.assertTrue(r.host_matches_remote)

    def test_target_linker_prefix(self):
        for target, ld in [
            ("arm64-unknown-linux-gnu", "ld"),
            ("x86_64-unknown-linux-gnu", "ld"),
            ("x86_64-unknown-freebsd", "ld"),
            ("x86_64-apple-darwin", "ld64"),
            ("ppc64-apple-darwin", "ld64"),
        ]:
            exec_root = Path("/home/project")
            working_dir = exec_root / "build-here"
            compiler = Path("../tools/host-platform/bin/rustc")
            source = Path("../foo/src/lib.rs")
            rlib = Path("obj/foo.rlib")
            command = _strs(
                [compiler, source, "-o", rlib, f"--target={target}"]
            )
            r = rustc_remote_wrapper.RustRemoteAction(
                ["--"] + command,
                exec_root=exec_root,
                working_dir=working_dir,
                auto_reproxy=False,
            )
            self.assertEqual(r.target_linker_prefix, ld)

    def test_remote_mode_ok_with_relative_c_sysroot(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/host-platform/bin/rustc")
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        c_sysroot = Path("generated/sys/root")  # relative
        target = "aarch64-unknown-linux-gnu"
        command = _strs(
            [
                compiler,
                source,
                "-o",
                rlib,
                "--crate-type=bin",
                f"--target={target}",
                f"-Clink-arg=--sysroot={c_sysroot}",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )
        self.assertEqual(r.c_sysroot, c_sysroot)
        self.assertFalse(r._c_sysroot_is_outside_exec_root)
        self.assertTrue(r.needs_linker)
        self.assertFalse(r._remote_disqualified())
        self.assertFalse(r.local_only)
        sysroot_files = list(r._c_sysroot_files())
        self.assertNotEqual(sysroot_files, [])

    def test_forced_local_mode_ok_with_external_absolute_c_sysroot(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/host-platform/bin/rustc")
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        c_sysroot = Path("/fancy/pants/local/SDK")  # absolute, external
        target = "aarch64-unknown-linux-gnu"
        command = _strs(
            [
                compiler,
                source,
                "-o",
                rlib,
                "--crate-type=bin",
                f"--target={target}",
                f"-Clink-arg=--sysroot={c_sysroot}",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )
        self.assertEqual(r.c_sysroot, c_sysroot)
        self.assertTrue(r._c_sysroot_is_outside_exec_root)
        self.assertTrue(r.needs_linker)
        self.assertTrue(r._remote_disqualified())
        self.assertTrue(r.local_only)
        with mock.patch.object(fuchsia, "c_sysroot_files") as mock_files:
            sysroot_files = list(r._c_sysroot_files())
        self.assertEqual(sysroot_files, [])
        mock_files.assert_not_called()

    def test_cdylib_rust_lld(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/mac-x64/bin/rustc")
        remote_compiler = Path("../tools/linux-x64/bin/rustc")
        remote_rust_lld = (
            remote_compiler.parent / fuchsia._REMOTE_RUST_LLD_RELPATH
        )
        source = Path("../foo/src/lib.rs")
        dylib = Path("obj/foo.dylib")
        command = _strs(
            [compiler, source, "--crate-type", "cdylib", "-o", dylib]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )
        mocks = self.generate_prepare_mocks()
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            with mock.patch.object(
                rustc_remote_wrapper.RustRemoteAction, "_local_depfile_inputs"
            ) as mock_deps:
                with mock.patch.object(
                    rustc_remote_wrapper.RustRemoteAction,
                    "_remote_rustc_shlibs",
                ) as mock_shlibs:
                    prepare_status = r.prepare()

        mock_deps.assert_called_once()
        mock_shlibs.assert_called_once()
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        self.assertIn(remote_compiler, remote_inputs)
        self.assertIn(remote_rust_lld, remote_inputs)

    def test_prepare_remote_cross_compile(self):
        host_platform = "mac-arm64"
        remote_platform = fuchsia.REMOTE_PLATFORM
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path(f"../tools/{host_platform}/bin/rustc")
        remote_compiler = Path(f"../tools/{remote_platform}/bin/rustc")
        linker = Path(f"../tools/{host_platform}/bin/linker")
        remote_linker = Path(f"../tools/{remote_platform}/bin/linker")
        remote_ld_path = Path(f"../tools/{remote_platform}/bin/ld.lld")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        libcxx = Path("../std/tools/bin/../lib/libc++.a")
        libcxx_norm = Path("../std/tools/lib/libc++.a")
        target = "powerpc-unknown-freebsd"
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs(
            [
                compiler,
                source,
                "-o",
                rlib,
                f"--target={target}",
                f"-Clinker={linker}",
                f"-Clink-arg={libcxx}",
                f"-Clink-arg=-fuse-ld=lld",
            ]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            host_platform=host_platform,
            auto_reproxy=False,
        )
        self.assertEqual(r.working_dir, working_dir)
        self.assertFalse(r.host_matches_remote)
        self.assertEqual(r.original_command, command)
        self.assertEqual(r.linker, linker)
        self.assertEqual(r.remote_linker, remote_linker)
        self.assertEqual(r.remote_ld_path, remote_ld_path)

        mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()
            remote_command = list(r.remote_compile_command())

        self.assertEqual(prepare_status, 0)  # success
        self.assertEqual(r.remote_compiler, remote_compiler)
        a = r.remote_action
        self.assertEqual(
            remote_command,
            _strs(
                [
                    remote_compiler,
                    source,
                    "-o",
                    rlib,
                    f"--target={target}",
                    f"-Clinker={remote_linker}",
                    f"-Clink-arg={libcxx_norm}",  # normalized
                    f"-Clink-arg=-fuse-ld=lld",
                    f"-Clink-arg=--ld-path={remote_ld_path}",  # added by wrapper
                    f"--sysroot=../some/random/sysroot",
                ]
            ),
        )
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs,
            set([remote_compiler, shlib_rel, libcxx, source] + deps),
        )
        self.assertEqual(remote_output_files, {rlib})

    def test_run_local_downloads_inputs_if_needed(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        input_rlib = Path("libintermediate.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_path = Path("obj/foo.rlib.d")
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs(
            [compiler, source, "-o", rlib, f"--emit=dep-info={depfile_path}"]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            [f"--inputs={input_rlib}", "--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        prepare_mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in prepare_mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source, input_rlib] + deps)
        )
        self.assertEqual(remote_output_files, {rlib, depfile_path})

        with mock.patch.object(
            remote_action.RemoteAction, "download_inputs", return_value={}
        ) as mock_download_inputs:
            with mock.patch.object(
                subprocess, "call", return_value=0
            ) as mock_call:
                run_status = r.run_local()

        mock_call.assert_called_once()
        self.assertEqual(run_status, 0)
        mock_download_inputs.assert_called_once()

    def test_post_run_actions(self):
        exec_root = Path("/home/project")
        working_dir = exec_root / "build-here"
        compiler = Path("../tools/bin/rustc")
        shlib = Path("tools/lib/librusteze.so")
        shlib_abs = exec_root / shlib
        shlib_rel = cl_utils.relpath(shlib_abs, start=working_dir)
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        deps = [Path("../foo/src/other.rs")]
        depfile_path = Path("obj/foo.rlib.d")
        depfile_contents = [str(d) + ":" for d in deps]
        command = _strs(
            [compiler, source, "-o", rlib, f"--emit=dep-info={depfile_path}"]
        )
        r = rustc_remote_wrapper.RustRemoteAction(
            ["--"] + command,
            exec_root=exec_root,
            working_dir=working_dir,
            auto_reproxy=False,
        )

        prepare_mocks = self.generate_prepare_mocks(
            depfile_contents=depfile_contents,
            compiler_shlibs=[shlib_rel],
        )
        with contextlib.ExitStack() as stack:
            for m in prepare_mocks:
                stack.enter_context(m)
            prepare_status = r.prepare()

        self.assertEqual(prepare_status, 0)  # success
        a = r.remote_action
        self.assertIsNotNone(a._post_remote_run_success_action)
        remote_inputs = set(a.inputs_relative_to_working_dir)
        remote_output_files = set(a.output_files_relative_to_working_dir)
        self.assertEqual(
            remote_inputs, set([compiler, shlib_rel, source] + deps)
        )
        self.assertEqual(remote_output_files, {rlib, depfile_path})

        run_mocks = [
            mock.patch.object(
                remote_action.RemoteAction,
                "_run_maybe_remotely",
                return_value=cl_utils.SubprocessResult(0),
            ),
            mock.patch.object(
                rustc_remote_wrapper.RustRemoteAction,
                "_depfile_exists",
                return_value=True,
            ),
            mock.patch.object(
                rustc_remote_wrapper.RustRemoteAction, "_cleanup"
            ),
        ]
        with contextlib.ExitStack() as stack:
            for m in run_mocks:
                stack.enter_context(m)
            with mock.patch.object(
                rustc_remote_wrapper.RustRemoteAction,
                "_rewrite_remote_or_local_depfile",
            ) as mock_rewrite:
                run_status = r.run()
            mock_rewrite.assert_called_with()

    def test_rewrite_remote_depfile(self):
        compiler = Path("../tools/bin/rustc")
        source = Path("../foo/src/lib.rs")
        rlib = Path("obj/foo.rlib")
        depfile_path = Path("obj/foo.rlib.d")
        with tempfile.TemporaryDirectory() as td:
            exec_root = Path(td)
            working_dir = exec_root / "build-here"
            command = _strs(
                [
                    compiler,
                    source,
                    "-o",
                    rlib,
                    f"--emit=dep-info={depfile_path}",
                ]
            )
            r = rustc_remote_wrapper.RustRemoteAction(
                ["--canonicalize_working_dir=true", "--"] + command,
                exec_root=exec_root,
                working_dir=working_dir,
                auto_reproxy=False,
            )

            prepare_mocks = self.generate_prepare_mocks()
            with contextlib.ExitStack() as stack:
                for m in prepare_mocks:
                    stack.enter_context(m)

                with mock.patch.object(
                    rustc_remote_wrapper.RustRemoteAction,
                    "_remote_inputs",
                    return_value=iter([]),
                ) as mock_inputs:
                    prepare_status = r.prepare()

            mock_inputs.assert_called_with()
            self.assertEqual(prepare_status, 0)  # success
            remote_cwd = r.remote_action.remote_working_dir
            depfile_abspath = working_dir / depfile_path
            depfile_abspath.parent.mkdir(parents=True, exist_ok=True)
            _write_file_contents(
                depfile_abspath,
                f"{remote_cwd}/obj/foo.rlib: {remote_cwd}/src/lib.rs\n",
            )
            r._rewrite_remote_or_local_depfile()
            new_deps = _read_file_contents(depfile_abspath)
            self.assertEqual(new_deps, "obj/foo.rlib: src/lib.rs\n")


class MainTests(unittest.TestCase):
    def test_help_implicit(self):
        # Just make sure help exits successfully, without any exceptions
        # due to argument parsing.
        stdout = io.StringIO()
        with contextlib.redirect_stdout(stdout):
            with mock.patch.object(
                sys, "exit", side_effect=ImmediateExit
            ) as mock_exit:
                with self.assertRaises(ImmediateExit):
                    rustc_remote_wrapper.main([])
        mock_exit.assert_called_with(0)

    def test_help_flag(self):
        # Just make sure help exits successfully, without any exceptions
        # due to argument parsing.
        stdout = io.StringIO()
        with contextlib.redirect_stdout(stdout):
            with mock.patch.object(
                sys, "exit", side_effect=ImmediateExit
            ) as mock_exit:
                with self.assertRaises(ImmediateExit):
                    rustc_remote_wrapper.main(["--help"])
        mock_exit.assert_called_with(0)

    def test_auto_relaunched_with_reproxy(self):
        argv = ["--", "rustc", "foo.rs", "-o", "foo.rlib"]
        with mock.patch.object(
            os.environ, "get", return_value=None
        ) as mock_env:
            with mock.patch.object(
                cl_utils, "exec_relaunch", side_effect=ImmediateExit
            ) as mock_relaunch:
                with self.assertRaises(ImmediateExit):
                    rustc_remote_wrapper.main(argv)
        mock_env.assert_called()
        mock_relaunch.assert_called_once()
        args, kwargs = mock_relaunch.call_args_list[0]
        relaunch_cmd = args[0]
        self.assertEqual(relaunch_cmd[0], str(fuchsia.REPROXY_WRAP))
        cmd_slices = cl_utils.split_into_subsequences(relaunch_cmd[1:], "--")
        reproxy_args, self_script, wrapped_command = cmd_slices
        self.assertEqual(reproxy_args, ["-v"])
        self.assertIn("python", self_script[0])
        self.assertTrue(self_script[-1].endswith("rustc_remote_wrapper.py"))
        self.assertEqual(wrapped_command, argv[1:])


if __name__ == "__main__":
    unittest.main()