Merge pull request #357 from kdarkhan/no-workspace

Enable use of cargo-fuzz without a separate workspace

README.md

@@ -26,6 +26,12 @@ $ cargo install -f cargo-fuzz
 
 Initialize a `cargo fuzz` project for your crate!
 
+### Add `fuzz` directory to `workspace.members` in root `Cargo.toml`
+
+`fuzz` directory can be either a part of an existing workspace (default)
+or use an independent workspace. If latter is desired, you can use
+`cargo fuzz init --fuzzing-workspace=true`.
+
 ### `cargo fuzz add <target>`
 
 Create a new fuzzing target!

src/options/init.rs

@@ -8,6 +8,10 @@ pub struct Init {
     /// Name of the first fuzz target to create
     pub target: String,
 
+    #[arg(long, value_parser = clap::builder::BoolishValueParser::new(), default_value = "false")]
+    /// Whether to create a separate workspace for fuzz targets crate
+    pub fuzzing_workspace: Option<bool>,
+
     #[command(flatten)]
     pub fuzz_dir_wrapper: FuzzDirWrapper,
 }

src/project.rs

@@ -66,7 +66,11 @@ impl FuzzProject {
         let mut cargo = fs::File::create(&cargo_toml)
             .with_context(|| format!("failed to create {}", cargo_toml.display()))?;
         cargo
-            .write_fmt(toml_template!(manifest.crate_name, manifest.edition))
+            .write_fmt(toml_template!(
+                manifest.crate_name,
+                manifest.edition,
+                init.fuzzing_workspace
+            ))
             .with_context(|| format!("failed to write to {}", cargo_toml.display()))?;
 
         let gitignore = fuzz_project.join(".gitignore");
@@ -137,7 +141,7 @@ impl FuzzProject {
             .arg(&build.triple);
         // we default to release mode unless debug mode is explicitly requested
         if !build.dev {
-            cmd.arg("--release");
+            cmd.args(["--release", "--config", "profile.release.debug=true"]);
         }
         if build.verbose {
             cmd.arg("--verbose");

src/templates.rs

@@ -1,5 +1,5 @@
 macro_rules! toml_template {
-    ($name:expr, $edition:expr) => {
+    ($name:expr, $edition:expr, $fuzzing_workspace:expr) => {
         format_args!(
             r##"[package]
 name = "{name}-fuzz"
@@ -14,20 +14,22 @@ libfuzzer-sys = "0.4"
 
 [dependencies.{name}]
 path = ".."
-
-# Prevent this from interfering with workspaces
-[workspace]
-members = ["."]
-
-[profile.release]
-debug = 1
-"##,
+{workspace}"##,
             name = $name,
             edition = if let Some(edition) = &$edition {
                 format!("edition = \"{}\"\n", edition)
             } else {
                 String::new()
             },
+            workspace = if let Some(true) = $fuzzing_workspace {
+                r##"
+# Use independent workspace for fuzzers
+[workspace]
+members = ["."]
+"##
+            } else {
+                ""
+            }
         )
     };
 }
@@ -41,6 +43,7 @@ name = "{0}"
 path = "fuzz_targets/{0}.rs"
 test = false
 doc = false
+bench = false
 "#,
             $name
         )

tests/tests/main.rs

@@ -17,9 +17,35 @@ fn help() {
 }
 
 #[test]
-fn init() {
+fn init_with_workspace() {
     let project = project("init").build();
+    project
+        .cargo_fuzz()
+        .arg("init")
+        .arg("--fuzzing-workspace=true")
+        .assert()
+        .success();
+    assert!(project.fuzz_dir().is_dir());
+    assert!(project.fuzz_cargo_toml().is_file());
+    assert!(project.fuzz_targets_dir().is_dir());
+    assert!(project.fuzz_target_path("fuzz_target_1").is_file());
+    project
+        .cargo_fuzz()
+        .arg("run")
+        .arg("fuzz_target_1")
+        .arg("--")
+        .arg("-runs=1")
+        .assert()
+        .success();
+}
+
+#[test]
+fn init_no_workspace() {
+    let mut project_builder = project("init_no_workspace");
+    let project = project_builder.build();
     project.cargo_fuzz().arg("init").assert().success();
+    project_builder.set_workspace_members(&["fuzz"]);
+
     assert!(project.fuzz_dir().is_dir());
     assert!(project.fuzz_cargo_toml().is_file());
     assert!(project.fuzz_targets_dir().is_dir());
@@ -28,20 +54,23 @@ fn init() {
         .cargo_fuzz()
         .arg("run")
         .arg("fuzz_target_1")
+        .arg("--fuzz-dir")
+        .arg(project.fuzz_dir().to_str().unwrap())
         .arg("--")
         .arg("-runs=1")
         .assert()
         .success();
 }
 
 #[test]
-fn init_with_target() {
+fn init_with_target_and_workspace() {
     let project = project("init_with_target").build();
     project
         .cargo_fuzz()
         .arg("init")
         .arg("-t")
         .arg("custom_target_name")
+        .arg("--fuzzing-workspace=true")
         .assert()
         .success();
     assert!(project.fuzz_dir().is_dir());

tests/tests/project.rs

@@ -118,6 +118,26 @@ impl ProjectBuilder {
         self.file(path, body)
     }
 
+    pub fn set_workspace_members(&mut self, members: &[&str]) -> &mut Self {
+        let cargo_toml = self.root().join("Cargo.toml");
+        let manifest = fs::read_to_string(cargo_toml.clone()).unwrap();
+
+        let with_members = manifest.replace(
+            "[workspace]",
+            &format!(
+                "[workspace]\nmembers=[{}]",
+                members
+                    .iter()
+                    .map(|&v| format!("\"{}\"", v))
+                    .collect::<Vec<_>>()
+                    .join(", ")
+            ),
+        );
+
+        fs::write(cargo_toml, with_members).unwrap();
+        self
+    }
+
     pub fn file<B: AsRef<Path>>(&mut self, path: B, body: &str) -> &mut Self {
         self._file(path.as_ref(), body);
         self