Rewrite it in Rust

.cirrus.yml

@@ -51,7 +51,8 @@ linux_task:
         - ninja -j 6 fish fish_tests
         - ninja fish_run_tests
 
-    only_if: $CIRRUS_REPO_OWNER == 'fish-shell'
+    # CI task disabled during RIIR transition
+    only_if: false && $CIRRUS_REPO_OWNER == 'fish-shell'
 
 linux_arm_task:
     matrix:
@@ -74,7 +75,8 @@ linux_arm_task:
         - file ./fish
         - ninja fish_run_tests
 
-    only_if: $CIRRUS_REPO_OWNER == 'fish-shell'
+    # CI task disabled during RIIR transition
+    only_if: false && $CIRRUS_REPO_OWNER == 'fish-shell'
 
 freebsd_task:
     matrix:
@@ -83,12 +85,14 @@ freebsd_task:
               image_family: freebsd-14-0-snap
         - name: FreeBSD 13
           freebsd_instance:
-              image: freebsd-13-0-release-amd64
+              image: freebsd-13-1-release-amd64
         - name: FreeBSD 12.3
           freebsd_instance:
               image: freebsd-12-3-release-amd64
     tests_script:
-        - pkg install -y cmake devel/pcre2 devel/ninja misc/py-pexpect git
+        - pkg install -y cmake-core devel/pcre2 devel/ninja misc/py-pexpect git-lite
+        # libclang.so is a required build dependency for rust-c++ ffi bridge
+        - pkg install -y llvm
         # BSDs have the following behavior: root may open or access files even if
         # the mode bits would otherwise disallow it. For example root may open()
         # a file with write privileges even if the file has mode 400. This breaks
@@ -99,8 +103,16 @@ freebsd_task:
         - mkdir build && cd build
         - chown -R fish-user ..
         - sudo -u fish-user -s whoami
+        # FreeBSD's pkg currently has rust 1.66.0 while we need rust 1.67.0+. Use rustup to install
+        # the latest, but note that it only installs rust per-user.
+        - sudo -u fish-user -s fetch -qo - https://sh.rustup.rs > rustup.sh
+        - sudo -u fish-user -s sh ./rustup.sh -y --profile=minimal
+        # `sudo -s ...` does not invoke a login shell so we need a workaround to make sure the
+        # rustup environment is configured for subsequent `sudo -s ...` commands.
+        # For some reason, this doesn't do the job:
+        # - sudo -u fish-user sh -c 'echo source \$HOME/.cargo/env >> $HOME/.cshrc'
         - sudo -u fish-user -s cmake -G Ninja -DCMAKE_BUILD_TYPE=Debug -DCTEST_PARALLEL_LEVEL=1 ..
-        - sudo -u fish-user -s ninja -j 6 fish fish_tests
-        - sudo -u fish-user -s ninja fish_run_tests
+        - sudo -u fish-user sh -c '. $HOME/.cargo/env; ninja -j 6 fish fish_tests'
+        - sudo -u fish-user sh -c '. $HOME/.cargo/env; ninja fish_run_tests'
 
     only_if: $CIRRUS_REPO_OWNER == 'fish-shell'

.github/workflows/main.yml

@@ -16,6 +16,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+    - name: SetupRust
+      uses: ATiltedTree/setup-rust@v1
+      with:
+        rust-version: beta
     - name: Install deps
       run: |
         sudo apt install gettext libncurses5-dev libpcre2-dev python3-pip tmux
@@ -42,6 +46,11 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+    - name: SetupRust
+      uses: ATiltedTree/setup-rust@v1
+      with:
+        rust-version: beta
+        targets: "i686-unknown-linux-gnu" # setup-rust wants this space-separated
     - name: Install deps
       run: |
         sudo apt update
@@ -53,10 +62,10 @@ jobs:
           CFLAGS: "-m32"
       run: |
         mkdir build && cd build
-        cmake -DFISH_USE_SYSTEM_PCRE2=OFF ..
+        cmake -DFISH_USE_SYSTEM_PCRE2=OFF -DRust_CARGO_TARGET=i686-unknown-linux-gnu ..
     - name: make
       run: |
-        make
+        make VERBOSE=1
     - name: make test
       run: |
         make test
@@ -67,6 +76,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+    - name: SetupRust
+      uses: ATiltedTree/setup-rust@v1
+      with:
+        rust-version: beta
     - name: Install deps
       run: |
         sudo apt install gettext libncurses5-dev libpcre2-dev python3-pip tmux
@@ -101,6 +114,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+    - name: SetupRust
+      uses: ATiltedTree/setup-rust@v1
+      with:
+        rust-version: beta
     - name: Install deps
       run: |
         sudo apt install gettext libncurses5-dev libpcre2-dev python3-pip tmux
@@ -127,6 +144,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v3
+    - name: SetupRust
+      uses: ATiltedTree/setup-rust@v1
+      with:
+        rust-version: beta
     - name: Install deps
       run: |
         sudo pip3 install pexpect

.gitignore

@@ -89,3 +89,14 @@ __pycache__
 /tags
 xcuserdata/
 
+# Generated by Cargo
+# will have compiled files and executables
+debug/
+target/
+
+# These are backup files generated by rustfmt
+**/*.rs.bk
+
+# MSVC Windows builds of rustc generate these, which store debugging information
+*.pdb
+

CMakeLists.txt

@@ -24,6 +24,8 @@ if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
     set(CMAKE_BUILD_TYPE "${DEFAULT_BUILD_TYPE}")
 endif()
 
+include(cmake/Rust.cmake)
+
 # Error out when linking statically, it doesn't work.
 if (CMAKE_EXE_LINKER_FLAGS MATCHES ".*-static.*")
     message(FATAL_ERROR "Fish does not support static linking")
@@ -43,6 +45,9 @@ endif()
 # - address, because that occurs for our mkostemp check (weak-linking requires us to compare `&mkostemp == nullptr`).
 add_compile_options(-Wall -Wextra -Wno-comment -Wno-address)
 
+# Get extra C++ files from Rust.
+get_property(FISH_EXTRA_SOURCES TARGET fish-rust PROPERTY fish_extra_cpp_files)
+
 if ((CMAKE_CXX_COMPILER_ID STREQUAL "Clang") OR (CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang"))
   add_compile_options(-Wunused-template -Wunused-local-typedef -Wunused-macros)
 endif()
@@ -53,6 +58,9 @@ add_compile_options(-fno-exceptions)
 # Undefine NDEBUG to keep assert() in release builds.
 add_definitions(-UNDEBUG)
 
+# Allow including Rust headers in normal (not bindgen) builds.
+add_definitions(-DINCLUDE_RUST_HEADERS)
+
 # Enable large files on GNU.
 add_definitions(-D_LARGEFILE_SOURCE
                 -D_LARGEFILE64_SOURCE
@@ -95,32 +103,32 @@ set(FISH_BUILTIN_SRCS
     src/builtins/bg.cpp src/builtins/bind.cpp src/builtins/block.cpp
     src/builtins/builtin.cpp src/builtins/cd.cpp src/builtins/command.cpp
     src/builtins/commandline.cpp src/builtins/complete.cpp src/builtins/contains.cpp
-    src/builtins/disown.cpp src/builtins/echo.cpp src/builtins/emit.cpp
+    src/builtins/disown.cpp
     src/builtins/eval.cpp src/builtins/exit.cpp src/builtins/fg.cpp
     src/builtins/function.cpp src/builtins/functions.cpp src/builtins/history.cpp
     src/builtins/jobs.cpp src/builtins/math.cpp src/builtins/printf.cpp src/builtins/path.cpp
     src/builtins/pwd.cpp src/builtins/random.cpp src/builtins/read.cpp
     src/builtins/realpath.cpp src/builtins/return.cpp src/builtins/set.cpp
     src/builtins/set_color.cpp src/builtins/source.cpp src/builtins/status.cpp
     src/builtins/string.cpp src/builtins/test.cpp src/builtins/type.cpp src/builtins/ulimit.cpp
-    src/builtins/wait.cpp)
+)
 
 # List of other sources.
 set(FISH_SRCS
     src/ast.cpp src/abbrs.cpp src/autoload.cpp src/color.cpp src/common.cpp src/complete.cpp
     src/env.cpp src/env_dispatch.cpp src/env_universal_common.cpp src/event.cpp
     src/exec.cpp src/expand.cpp src/fallback.cpp src/fd_monitor.cpp src/fish_version.cpp
-    src/flog.cpp src/function.cpp src/future_feature_flags.cpp src/highlight.cpp
+    src/flog.cpp src/function.cpp src/highlight.cpp
     src/history.cpp src/history_file.cpp src/input.cpp src/input_common.cpp
     src/io.cpp src/iothread.cpp src/job_group.cpp src/kill.cpp
     src/null_terminated_array.cpp src/operation_context.cpp src/output.cpp
     src/pager.cpp src/parse_execution.cpp src/parse_tree.cpp src/parse_util.cpp
     src/parser.cpp src/parser_keywords.cpp src/path.cpp src/postfork.cpp
-    src/proc.cpp src/re.cpp src/reader.cpp src/redirection.cpp src/screen.cpp
-    src/signal.cpp src/termsize.cpp src/timer.cpp src/tinyexpr.cpp
-    src/tokenizer.cpp src/topic_monitor.cpp src/trace.cpp src/utf8.cpp src/util.cpp
-    src/wait_handle.cpp src/wcstringutil.cpp src/wgetopt.cpp src/wildcard.cpp 
-    src/wutil.cpp src/fds.cpp
+    src/proc.cpp src/re.cpp src/reader.cpp src/screen.cpp
+    src/signals.cpp src/termsize.cpp src/timer.cpp src/tinyexpr.cpp
+    src/trace.cpp src/utf8.cpp
+    src/wait_handle.cpp src/wcstringutil.cpp src/wgetopt.cpp src/wildcard.cpp
+    src/wutil.cpp src/fds.cpp src/rustffi.cpp
 )
 
 # Header files are just globbed.
@@ -133,6 +141,11 @@ configure_file(${CMAKE_CURRENT_SOURCE_DIR}/config_cmake.h.in
                ${CMAKE_CURRENT_BINARY_DIR}/config.h)
 include_directories(${CMAKE_CURRENT_BINARY_DIR})
 
+# Pull in our src directory for headers searches, but only quoted ones.
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -iquote ${CMAKE_CURRENT_SOURCE_DIR}/src")
+
+
+
 # Set up standard directories.
 include(GNUInstallDirs)
 add_definitions(-D_UNICODE=1
@@ -175,8 +188,10 @@ endfunction(FISH_LINK_DEPS_AND_SIGN)
 add_library(fishlib STATIC ${FISH_SRCS} ${FISH_BUILTIN_SRCS})
 target_sources(fishlib PRIVATE ${FISH_HEADERS})
 target_link_libraries(fishlib
+  fish-rust
   ${CURSES_LIBRARY} ${CURSES_EXTRA_LIBRARY} Threads::Threads ${CMAKE_DL_LIBS}
-  ${PCRE2_LIB} ${Intl_LIBRARIES} ${ATOMIC_LIBRARY})
+  ${PCRE2_LIB} ${Intl_LIBRARIES} ${ATOMIC_LIBRARY}
+  "fish-rust")
 target_include_directories(fishlib PRIVATE
   ${CURSES_INCLUDE_DIRS})
 

CONTRIBUTING.rst

@@ -420,8 +420,8 @@ Include What You Use
 You should not depend on symbols being visible to a ``*.cpp`` module
 from ``#include`` statements inside another header file. In other words
 if your module does ``#include "common.h"`` and that header does
-``#include "signal.h"`` your module should not assume the sub-include is
-present. It should instead directly ``#include "signal.h"`` if it needs
+``#include "signals.h"`` your module should not assume the sub-include is
+present. It should instead directly ``#include "signals.h"`` if it needs
 any symbol from that header. That makes the actual dependencies much
 clearer. It also makes it easy to modify the headers included by a
 specific header file without having to worry that will break any module

README.rst

@@ -148,6 +148,7 @@ Dependencies
 
 Compiling fish requires:
 
+-  Rust (version 1.67 or later)
 -  a C++11 compiler (g++ 4.8 or later, or clang 3.3 or later)
 -  CMake (version 3.5 or later)
 -  a curses implementation such as ncurses (headers and libraries)

cmake/Rust.cmake

@@ -0,0 +1,49 @@
+include(FetchContent)
+
+# Don't let Corrosion's tests interfere with ours.
+set(CORROSION_TESTS OFF CACHE BOOL "" FORCE)
+
+FetchContent_Declare(
+    Corrosion
+    GIT_REPOSITORY https://github.com/ridiculousfish/corrosion
+    GIT_TAG fish
+)
+
+FetchContent_MakeAvailable(Corrosion)
+
+set(fish_rust_target "fish-rust")
+
+set(fish_autocxx_gen_dir "${CMAKE_BINARY_DIR}/fish-autocxx-gen/")
+
+corrosion_import_crate(
+    MANIFEST_PATH "${CMAKE_SOURCE_DIR}/fish-rust/Cargo.toml"
+    FEATURES "fish-ffi-tests"
+)
+
+# We need the build dir because cxx puts our headers in there.
+# Corrosion doesn't expose the build dir, so poke where we shouldn't.
+if (Rust_CARGO_TARGET)
+    set(rust_target_dir "${CMAKE_BINARY_DIR}/cargo/build/${_CORROSION_RUST_CARGO_TARGET}")
+else()
+    set(rust_target_dir "${CMAKE_BINARY_DIR}/cargo/build/${_CORROSION_RUST_CARGO_HOST_TARGET}")
+    corrosion_set_hostbuild(${fish_rust_target})
+endif()
+
+# Tell Cargo where our build directory is so it can find config.h.
+corrosion_set_env_vars(${fish_rust_target} "FISH_BUILD_DIR=${CMAKE_BINARY_DIR}" "FISH_AUTOCXX_GEN_DIR=${fish_autocxx_gen_dir}" "FISH_RUST_TARGET_DIR=${rust_target_dir}")
+
+target_include_directories(${fish_rust_target} INTERFACE
+    "${rust_target_dir}/cxxbridge/${fish_rust_target}/src/"
+    "${fish_autocxx_gen_dir}/include/"
+)
+
+# Tell fish what extra C++ files to compile.
+define_property(
+    TARGET PROPERTY fish_extra_cpp_files
+    BRIEF_DOCS "Extra C++ files to compile for fish."
+    FULL_DOCS "Extra C++ files to compile for fish."
+)
+
+set_property(TARGET ${fish_rust_target} PROPERTY fish_extra_cpp_files
+    "${fish_autocxx_gen_dir}/cxx/gen0.cxx"
+)

cmake/Tests.cmake

@@ -175,3 +175,19 @@ foreach(PEXPECT ${PEXPECTS})
   set_tests_properties(${PEXPECT} PROPERTIES ENVIRONMENT FISH_FORCE_COLOR=1)
   add_test_target("${PEXPECT}")
 endforeach(PEXPECT)
+
+# Rust stuff.
+add_test(
+    NAME "cargo-test"
+    COMMAND cargo test
+    WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}/fish-rust"
+)
+set_tests_properties("cargo-test" PROPERTIES SKIP_RETURN_CODE ${SKIP_RETURN_CODE})
+add_test_target("cargo-test")
+
+add_test(
+    NAME "cargo-test-widestring"
+    COMMAND cargo test
+    WORKING_DIRECTORY "${CMAKE_SOURCE_DIR}/fish-rust/widestring-suffix/"
+)
+add_test_target("cargo-test-widestring")