feat: basic support for tests

README.md

@@ -77,8 +77,8 @@ $ nix-shell --command 'cargo install cargo-instruments' --pure -p \
 
 `cargo-instruments` requires a binary target to run. By default, it will try to
 build the current crate's `main.rs`. You can specify an alternative binary by
-using the `--bin` or `--example` flags, or a benchmark target with the `--bench`
-flag.
+using the `--bin` or `--example` flags, a test target with the `--test` flag,
+or a benchmark target with the `--bench` flag.
 
 Assuming your crate has one binary target named `mybin`, and you want to profile
 using the `Allocations` Instruments template:
@@ -154,6 +154,7 @@ OPTIONS:
     -p, --package <NAME>               Specify package for example/bin/bench
         --profile <NAME>               Pass --profile NAME to cargo
     -t, --template <TEMPLATE>          Specify the instruments template to run
+        --test <NAME>                  Test target to run
         --time-limit <MILLIS>          Limit recording time to the specified value (in milliseconds)
     -o, --output <PATH>                Output .trace file to the given path
 
@@ -219,6 +220,15 @@ $ cargo instruments -t alloc
 $ cargo instruments -t Allocations --example my_example --time-limit 10000 --open
 ```
 
+```shell
+# Profile a single test scanario with the File Activity template
+#
+# You will find `your_library_name` name by running `cargo test` and checking the 'Running' line.
+# e.g. Running unittests src/main.rs (target/debug/deps/your_library_name-3cabce0a041cfeed)
+# Optionally, you can provide a specific test case after the -- marker
+$ cargo instruments -t io --test your_library_name -- opt::tests::specific_test
+```
+
 ## Resources
 
 [Instruments Help][instruments]

src/app.rs

@@ -146,6 +146,13 @@ fn build_target(cargo_options: &CargoOpts, workspace: &Workspace) -> Result<Path
             .find(|unit_output| unit_output.unit.target.name() == bench)
             .map(|unit_output| unit_output.path.clone())
             .ok_or_else(|| anyhow!("no benchmark '{}'", bench))
+    } else if let Target::Test(ref test) = cargo_options.target {
+        result
+            .tests
+            .iter()
+            .find(|unit_output| unit_output.unit.target.name() == test)
+            .map(|unit_output| unit_output.path.clone())
+            .ok_or_else(|| anyhow!("no test '{}'", test))
     } else {
         match result.binaries.as_slice() {
             [unit_output] => Ok(unit_output.path.clone()),
@@ -177,19 +184,20 @@ fn make_compile_opts(cargo_options: &CargoOpts, cfg: &Config) -> Result<CompileO
     compile_options.spec = cargo_options.package.clone().into();
 
     if cargo_options.target != Target::Main {
-        let (bins, examples, benches) = match &cargo_options.target {
-            Target::Bin(bin) => (vec![bin.clone()], vec![], vec![]),
-            Target::Example(bin) => (vec![], vec![bin.clone()], vec![]),
-            Target::Bench(bin) => (vec![], vec![], vec![bin.clone()]),
+        let (bins, examples, benches, tests) = match &cargo_options.target {
+            Target::Bin(bin) => (vec![bin.clone()], vec![], vec![], vec![]),
+            Target::Example(bin) => (vec![], vec![bin.clone()], vec![], vec![]),
+            Target::Bench(bin) => (vec![], vec![], vec![bin.clone()], vec![]),
+            Target::Test(bin) => (vec![], vec![], vec![], vec![bin.clone()]),
             _ => unreachable!(),
         };
 
         compile_options.filter = CompileFilter::from_raw_arguments(
             false,
             bins,
             false,
-            Vec::new(),
-            false,
+            vec![],
+            !tests.is_empty(),
             examples,
             false,
             benches,

src/opt.rs

@@ -56,6 +56,10 @@ pub(crate) struct AppConfig {
     #[structopt(long, group = "target", value_name = "NAME")]
     bench: Option<String>,
 
+    /// Test target to run
+    #[structopt(long, group = "target", value_name = "NAME")]
+    test: Option<String>,
+
     /// Pass --release to cargo
     #[structopt(long, conflicts_with = "profile")]
     release: bool,
@@ -119,6 +123,7 @@ pub(crate) enum Target {
     Example(String),
     Bin(String),
     Bench(String),
+    Test(String),
 }
 
 /// The package in which to look for the specified target (example/bin/bench)
@@ -155,6 +160,7 @@ impl fmt::Display for Target {
             Target::Example(bin) => write!(f, "examples/{}.rs", bin),
             Target::Bin(bin) => write!(f, "bin/{}.rs", bin),
             Target::Bench(bench) => write!(f, "bench {}", bench),
+            Target::Test(test) => write!(f, "test {}", test),
         }
     }
 }
@@ -192,14 +198,16 @@ impl AppConfig {
         }
     }
 
-    // valid target: --example,  --bin, --bench
+    // valid target: --example,  --bin, --bench, --harness
     fn get_target(&self) -> Target {
         if let Some(ref example) = self.example {
             Target::Example(example.clone())
         } else if let Some(ref bin) = self.bin {
             Target::Bin(bin.clone())
         } else if let Some(ref bench) = self.bench {
             Target::Bench(bench.clone())
+        } else if let Some(ref test) = self.test {
+            Target::Test(test.clone())
         } else {
             Target::Main
         }