Add testing infrastructure for slang

.clang-format

@@ -0,0 +1,18 @@
+---
+Language:        Cpp
+BasedOnStyle:    LLVM
+
+# 4 spaces everywhere
+IndentWidth:     4
+TabWidth:        4
+UseTab:          Never
+ContinuationIndentWidth: 4
+
+# Modern C++ style
+Standard:        c++20
+ColumnLimit:     120
+PointerAlignment: Left
+
+# Organize includes
+SortIncludes:    true
+IncludeBlocks:   Regroup

.clangd

@@ -0,0 +1,15 @@
+If:
+  PathMatch: (^|.*/)crates/bender-slang/cpp/.*\.(h|hpp|hh|c|cc|cpp|cxx)$
+CompileFlags:
+  Add:
+    - -std=c++20
+    - -fno-cxx-modules
+    - -I.
+    - -I../../../crates
+    - -I../vendor/slang/include
+    - -I../vendor/slang/external
+    - -I../../../target/slang-generated-include
+    - -I../../../target/cxxbridge
+    - -DSLANG_USE_MIMALLOC=1
+    - -DSLANG_USE_THREADS=1
+    - -DSLANG_BOOST_SINGLE_HEADER=1

.github/workflows/ci.yml

@@ -4,7 +4,6 @@ on:
   push:
     branches: [master]
   pull_request:
-    branches: [master]
   workflow_dispatch:
 
 jobs:
@@ -26,13 +25,10 @@ jobs:
       - uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: ${{ matrix.rust}}
-          components: rustfmt
       - name: Build
         run: cargo build --all-features
       - name: Cargo Test
         run: cargo test --workspace --all-features
-      - name: Format (fix with `cargo fmt`)
-        run: cargo fmt -- --check
       - name: Run unit-tests
         run: tests/run_all.sh
         shell: bash

.github/workflows/formatting.yml

@@ -0,0 +1,35 @@
+name: formatting
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+  workflow_dispatch:
+
+jobs:
+  rustfmt:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          submodules: recursive
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: stable
+          components: rustfmt
+      - name: Check Rust formatting
+        run: cargo fmt -- --check
+
+  clang-format:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v6
+        with:
+          submodules: recursive
+      - name: Check C/C++ formatting
+        uses: DoozyX/clang-format-lint-action@v0.18
+        with:
+          source: "."
+          extensions: "h,hpp,c,cc,cpp,cxx"
+          exclude: "./crates/bender-slang/vendor"

.gitignore

@@ -1,6 +1,9 @@
-.*
-!/.ci/
-!.git*
-!.travis.yml
-/target
-/tests/tmp
+# Cargo build files
+target
+
+# Temporary test files
+tests/**/tmp
+tests/**/.bender
+
+# clangd
+.cache/clangd

crates/bender-slang/build.rs

@@ -1,6 +1,37 @@
 // Copyright (c) 2025 ETH Zurich
 // Tim Fischer <fischeti@iis.ee.ethz.ch>
 
+#[cfg(unix)]
+// We create a symlink from the generated include directory to a stable location in the target directory
+// so that tools like clangd can find the headers without needing to know the exact OUT_DIR path.
+// This is purely for improving the development experience and is not necessary for the build itself.
+fn refresh_include_symlink(generated_include_dir: &std::path::Path) {
+    use std::ffi::OsStr;
+    use std::fs;
+    use std::os::unix::fs::symlink;
+    use std::path::PathBuf;
+
+    let Ok(out_dir) = std::env::var("OUT_DIR") else {
+        return;
+    };
+    let out_dir = PathBuf::from(out_dir);
+
+    let Some(target_root) = out_dir
+        .ancestors()
+        .find(|path| path.file_name() == Some(OsStr::new("target")))
+    else {
+        return;
+    };
+
+    let stable_link = target_root.join("slang-generated-include");
+    let _ = fs::remove_file(&stable_link);
+    let _ = fs::remove_dir_all(&stable_link);
+    let _ = symlink(generated_include_dir, &stable_link);
+}
+
+#[cfg(not(unix))]
+fn refresh_include_symlink(_generated_include_dir: &std::path::Path) {}
+
 fn main() {
     let target_os = std::env::var("CARGO_CFG_TARGET_OS").unwrap();
     let target_env = std::env::var("CARGO_CFG_TARGET_ENV").unwrap();
@@ -64,6 +95,11 @@ fn main() {
     let dst = slang_lib.build();
     let lib_dir = dst.join("lib");
 
+    // Create a symlink for the generated include directory
+    if target_os == "linux" || target_os == "macos" {
+        refresh_include_symlink(&dst.join("include"));
+    }
+
     // Configure Linker to find Slang static library
     println!("cargo:rustc-link-search=native={}", lib_dir.display());
     println!("cargo:rustc-link-lib=static=svlang");
@@ -97,7 +133,7 @@ fn main() {
         let compiler = std::env::var("CXX").unwrap_or_else(|_| "g++".to_string());
         // We search for the static libstdc++ file using g++
         let output = std::process::Command::new(&compiler)
-            .args(&["-print-file-name=libstdc++.a"])
+            .args(["-print-file-name=libstdc++.a"])
             .output()
             .expect("Failed to run g++");
 

crates/bender-slang/cpp/slang_bridge.cpp

@@ -4,8 +4,6 @@
 #include "slang_bridge.h"
 
 #include "bender-slang/src/lib.rs.h"
-#include "slang/diagnostics/DiagnosticEngine.h"
-#include "slang/diagnostics/TextDiagnosticClient.h"
 #include "slang/syntax/CSTSerializer.h"
 #include "slang/syntax/SyntaxPrinter.h"
 #include "slang/syntax/SyntaxVisitor.h"
@@ -17,7 +15,6 @@
 #include <unordered_set>
 
 using namespace slang;
-using namespace slang::driver;
 using namespace slang::syntax;
 using namespace slang::parsing;
 

crates/bender-slang/cpp/slang_bridge.h

@@ -7,13 +7,13 @@
 #include "rust/cxx.h"
 #include "slang/diagnostics/DiagnosticEngine.h"
 #include "slang/diagnostics/TextDiagnosticClient.h"
-#include "slang/driver/Driver.h"
+#include "slang/parsing/Preprocessor.h"
 #include "slang/syntax/SyntaxTree.h"
+#include "slang/text/SourceManager.h"
 
 #include <cstddef>
 #include <cstdint>
 #include <memory>
-#include <string>
 #include <vector>
 
 struct SlangPrintOpts;

crates/bender-slang/tests/basic.rs

@@ -0,0 +1,37 @@
+use std::path::PathBuf;
+
+fn fixture_path(rel: &str) -> String {
+    PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+        .join("../..")
+        .join("tests/pickle")
+        .join(rel)
+        .canonicalize()
+        .expect("valid fixture path")
+        .to_string_lossy()
+        .into_owned()
+}
+
+#[test]
+fn parse_valid_file_succeeds() {
+    let mut session = bender_slang::SlangSession::new();
+    let files = vec![fixture_path("src/top.sv")];
+    let includes = vec![fixture_path("include")];
+    let defines = vec![];
+    assert!(session.parse_group(&files, &includes, &defines).is_ok());
+    assert_eq!(session.tree_count(), 1);
+}
+
+#[test]
+fn parse_invalid_file_returns_parse_error() {
+    let mut session = bender_slang::SlangSession::new();
+    let files = vec![fixture_path("src/broken.sv")];
+    let includes = vec![];
+    let defines = vec![];
+    let result = session.parse_group(&files, &includes, &defines);
+
+    match result {
+        Err(bender_slang::SlangError::ParseGroup { .. }) => {}
+        Err(other) => panic!("expected SlangError::ParseGroup, got {other}"),
+        Ok(_) => panic!("expected parse to fail"),
+    }
+}

tests/cli_regression.rs

@@ -161,5 +161,8 @@ regression_tests! {
     packages:                       &["packages"],
     packages_graph:                 &["packages", "--graph"],
     packages_flat:                  &["packages", "--flat"],
+    // Enable once the golden binary is built with `slang` support.
+    // pickle_basic:                   &["pickle", "--target", "top"],
+    // pickle_top_trim:                &["pickle", "--target", "top", "--top", "top"],
 
 }

tests/pickle.rs

@@ -0,0 +1,75 @@
+// Copyright (c) 2025 ETH Zurich
+// Tim Fischer <fischeti@iis.ee.ethz.ch>
+
+#[cfg(feature = "slang")]
+mod tests {
+    use assert_cmd::cargo;
+
+    fn run_pickle(args: &[&str]) -> String {
+        let mut full_args = vec!["-d", "tests/pickle", "pickle"];
+        full_args.extend(args);
+
+        let out = cargo::cargo_bin_cmd!()
+            .args(&full_args)
+            .output()
+            .expect("Failed to execute bender binary");
+
+        assert!(
+            out.status.success(),
+            "pickle command failed.\nstdout:\n{}\nstderr:\n{}",
+            String::from_utf8_lossy(&out.stdout),
+            String::from_utf8_lossy(&out.stderr)
+        );
+
+        String::from_utf8(out.stdout).expect("stdout must be utf-8")
+    }
+
+    #[test]
+    fn pickle_top_trim_filters_unreachable_modules() {
+        let full = run_pickle(&["--target", "top"]);
+        assert!(full.contains("module unused_top;"));
+        assert!(full.contains("module unused_leaf;"));
+
+        let trimmed = run_pickle(&["--target", "top", "--top", "top"]);
+        assert!(trimmed.contains("module top ("));
+        assert!(trimmed.contains("module core;"));
+        assert!(trimmed.contains("module leaf;"));
+        assert!(!trimmed.contains("module unused_top;"));
+        assert!(!trimmed.contains("module unused_leaf;"));
+    }
+
+    #[test]
+    fn pickle_rename_applies_prefix_and_suffix() {
+        let renamed = run_pickle(&[
+            "--target", "top", "--top", "top", "--prefix", "p_", "--suffix", "_s",
+        ]);
+
+        assert!(renamed.contains("module p_top_s ("));
+        assert!(renamed.contains("module p_core_s;"));
+        assert!(renamed.contains("module p_leaf_s;"));
+    }
+
+    #[test]
+    fn pickle_exclude_rename_keeps_selected_names() {
+        let renamed = run_pickle(&[
+            "--target",
+            "top",
+            "--top",
+            "top",
+            "--prefix",
+            "p_",
+            "--suffix",
+            "_s",
+            "--exclude-rename",
+            "top",
+            "--exclude-rename",
+            "core",
+        ]);
+
+        assert!(renamed.contains("module top ("));
+        assert!(renamed.contains("module core;"));
+        assert!(renamed.contains("module p_leaf_s;"));
+        assert!(!renamed.contains("module p_top_s ("));
+        assert!(!renamed.contains("module p_core_s;"));
+    }
+}

tests/pickle/Bender.lock

@@ -0,0 +1 @@
+packages: {}

tests/pickle/Bender.yml

@@ -0,0 +1,19 @@
+package:
+  name: pickle_repo
+
+sources:
+  - defines:
+      ENABLE_LOGGING: 1
+    files:
+      - src/common_pkg.sv
+      - src/bus_intf.sv
+      - src/leaf.sv
+      - src/core.sv
+      - src/unused_leaf.sv
+      - src/unused_top.sv
+
+  - target: top
+    include_dirs:
+      - include
+    files:
+      - src/top.sv

tests/pickle/include/macros.svh

@@ -0,0 +1,6 @@
+// Simple macro to test if includes are resolved correctly
+`define LOG(msg) \
+    $display("[LOG]: %s", msg);
+
+// A constant used in the RTL
+localparam int unsigned DataWidth = 32;

tests/pickle/src/broken.sv

@@ -0,0 +1,2 @@
+module broken(;
+endmodule

tests/pickle/src/bus_intf.sv

@@ -0,0 +1,21 @@
+interface bus_intf #(
+    parameter int Width = 32
+) (
+    input logic clk
+);
+    logic [Width-1:0] addr;
+    logic [Width-1:0] data;
+    logic             valid;
+    logic             ready;
+
+    modport master (
+        output addr, data, valid,
+        input  ready
+    );
+
+    modport slave (
+        input  addr, data, valid,
+        output ready
+    );
+
+endinterface

tests/pickle/src/common_pkg.sv

@@ -0,0 +1,13 @@
+package common_pkg;
+
+    typedef enum logic [1:0] {
+        Idle = 2'b00,
+        Busy = 2'b01,
+        Error = 2'b11
+    } state_t;
+
+    function automatic logic is_error(state_t s);
+        return s == Error;
+    endfunction
+
+endpackage

tests/pickle/src/core.sv

@@ -0,0 +1,3 @@
+module core;
+    leaf u_leaf();
+endmodule

tests/pickle/src/leaf.sv

@@ -0,0 +1,2 @@
+module leaf;
+endmodule