Unit testing framework

Cargo.toml

@@ -105,5 +105,21 @@ required-features = ["smt", "zok", "r1cs"]
 name = "opa_bench"
 required-features = ["lp", "aby"]
 
+[[example]]
+name = "ztest"
+required-features = ["smt", "zokc", "bellman"]
+
 [profile.release]
 debug = true
+
+[[test]]
+name = "inmem"
+required-features = ["smt", "zokc", "bellman"]
+
+[[test]]
+name = "ztest_e2e"
+required-features = ["smt", "zokc", "bellman"]
+
+[[test]]
+name = "zok_test_inputs"
+required-features = ["smt", "zokc"]

examples/README.md

@@ -0,0 +1,35 @@
+# CirC examples
+
+## `ztest.rs` — Unit-test circuits written in ZoKratesCurly
+
+`ztest` discovers and runs `@test` functions in a ZoKratesCurly (`.zok`) program.
+Each test is compiled to R1CS on its own and its assertions are checked with a
+proof backend, so a test passes only if the circuit is satisfiable for the given
+inputs.
+
+**Step 1: Write tests**
+
+Annotate test functions with:
+
+```
+@test(backend = {groth16, mirage}) <input1> = <val1>, <input2> = <val2>, ...;
+```
+
+See [ZoKratesCurly/pf/ztest/coverage_test.zok](ZoKratesCurly/pf/ztest/coverage_test.zok)
+for a worked example covering backend selection, scalar/array/tuple inputs, and
+public/private visibility.
+
+Rules for an annotated function:
+
+- The backend defaults to `groth16` and may be omitted.
+- It behaves like `main`: it must have no generics and no return value.
+- It must make assertions (that is what the test verifies).
+
+**Step 2: Run tests**
+
+Build with the features the backends need, then point `ztest` at a file:
+
+```
+cargo run --example ztest --features smt,zokc,bellman -- \
+  examples/ZoKratesCurly/pf/ztest/coverage_test.zok
+```

examples/ZoKratesCurly/pf/no_main.zok

@@ -0,0 +1,7 @@
+def add(private field a, public field b) -> field {
+    return a + b;
+}
+
+def square(private field x) -> field {
+    return x * x;
+}

examples/ZoKratesCurly/pf/ztest/coverage_test.zok

@@ -0,0 +1,99 @@
+// Simple @test coverage: backend selection, scalar, array, and tuple inputs,
+// and private/public visibility. All tests pass. Run:
+//   cargo run --example ztest --features smt,zokc,bellman -- examples/ZoKratesCurly/pf/ztest/coverage_test.zok
+
+// ---- scalar inputs ----
+
+@test x = 5;
+def test_field(private field x) {
+    assert(x == 5);
+}
+
+@test(backend = mirage) a = 4, b = 6;
+def test_add(private field a, private field b) {
+    assert(a + b == 10);
+}
+
+@test b = true;
+def test_bool(private bool b) {
+    assert(b);
+}
+
+@test x = 7u32;
+def test_u32(private u32 x) {
+    assert(x * 2 == 14u32);
+}
+
+// ---- scalar visibility corners ----
+
+@test a = 3, b = 4;
+def test_all_public(public field a, public field b) {
+    assert(a + b == 7);
+}
+
+@test a = 3, b = 4;
+def test_mixed_visibility(private field a, public field b) {
+    assert(a + b == 7);
+}
+
+// ---- array inputs ----
+
+@test xs = [1, 2, 3];
+def test_array(private field[3] xs) {
+    assert(xs[0] + xs[1] == xs[2]);
+}
+
+@test A = [[1, 2], [3, 4]];
+def test_nested_array(private field[2][2] A) {
+    assert(A[0][0] == 1);
+    assert(A[1][1] == 4);
+}
+
+@test xs = [1, 2];
+def test_public_array(public field[2] xs) {
+    assert(xs[0] + xs[1] == 3);
+}
+
+// ---- array + scalar together ----
+
+@test k = 10, xs = [1, 2];
+def test_array_and_scalar(private field k, public field[2] xs) {
+    assert(k + xs[0] == 11);
+    assert(k + xs[1] == 12);
+}
+
+// ---- tuple inputs ----
+
+@test t = (4, true);
+def test_tuple(private (field, bool) t) {
+    assert(t.0 == 4);
+    assert(t.1);
+}
+
+// A singleton tuple needs the trailing comma: (5,) is a 1-tuple, (5) is
+// just a parenthesized expression.
+@test t = (5,);
+def test_singleton_tuple(private (field,) t) {
+    assert(t.0 == 5);
+}
+
+@test t = ([1, 2], (true, 3));
+def test_nested_tuple(private (field[2], (bool, u32)) t) {
+    assert(t.0[0] + t.0[1] == 3);
+    assert(t.1.0);
+    assert(t.1.1 == 3u32);
+}
+
+@test pairs = [(1, 2), (3, 4)];
+def test_array_of_tuples(private (field, u32)[2] pairs) {
+    assert(pairs[0].0 == 1);
+    assert(pairs[0].1 == 2u32);
+    assert(pairs[1].0 == 3);
+    assert(pairs[1].1 == 4u32);
+}
+
+@test t = (7, 9);
+def test_public_tuple(public (field, u32) t) {
+    assert(t.0 == 7);
+    assert(t.1 == 9u32);
+}

examples/circ.rs

@@ -215,6 +215,7 @@ fn main() {
         DeterminedLanguage::ZsharpCurly => {
             let inputs = zsharpcurly::Inputs {
                 file: options.path,
+                entry: "main".to_string(),
                 mode,
             };
             ZSharpCurlyFE::gen(inputs)

examples/zcxi.rs

@@ -34,6 +34,7 @@ fn main() {
     circ::cfg::set(&options.circ);
     let inputs = Inputs {
         file: options.zsharp_path,
+        entry: "main".to_string(),
         mode: Mode::Proof,
     };
     let scalar_input_values = match options.inputs_path.as_ref() {

examples/ztest.rs

@@ -0,0 +1,167 @@
+//! Unit-test runner for ZoKratesCurly programs.
+//! Reads a .zok file, finds every function marked with a @test annotation,
+//! evaluates its annotation inputs to concrete values, then runs each test
+//! through the full in-memory proof pipeline:
+//!   compile (test fn as entry point) -> assert check -> setup -> prove -> verify
+//! and prints ok / FAILED per test. A test passes when its assertions hold for
+//! the supplied inputs and its proof verifies. Assertions are evaluated
+//! directly on the unoptimized IR before proof generation. Tests use
+//! Groth16 by default and may select Mirage in the annotation.
+//!
+//! The per-test execution logic lives in [`circ::test_runner`]; this file is
+//! the CLI wrapper.
+use bls12_381::Bls12;
+use circ::cfg::{clap, CircOpt};
+use circ::front::zsharpcurly::{TestBackend, ZSharpCurlyFE};
+use circ::front::Mode;
+use circ::ir::term::Value;
+use circ::target::r1cs::{bellman::Bellman, mirage::Mirage};
+use circ::test_runner::{catch, run_test, Outcome};
+use clap::Parser;
+use std::path::PathBuf;
+
+#[derive(Debug, Parser)]
+#[command(
+    name = "ztest",
+    about = "Run @test functions in a ZoKratesCurly program"
+)]
+struct Options {
+    /// Input file
+    #[arg(name = "PATH")]
+    path: PathBuf,
+
+    #[command(flatten)]
+    circ: CircOpt,
+}
+
+/// Render a concrete Value as a plain number/bool, without the field
+/// modulus that Value's own Display appends (e.g. `9` instead of `#f9m524...`).
+fn pretty_value(v: &Value) -> String {
+    match v {
+        Value::Field(f) => f.i().to_string(),
+        Value::BitVector(b) => b.uint().to_string(),
+        Value::Bool(b) => b.to_string(),
+        Value::Array(a) => format!(
+            "[{}]",
+            a.values()
+                .iter()
+                .map(pretty_value)
+                .collect::<Vec<_>>()
+                .join(", ")
+        ),
+        // Singletons print as `(5,)` — the trailing comma matches how they
+        // must be written in source.
+        Value::Tuple(vs) if vs.len() == 1 => format!("({},)", pretty_value(&vs[0])),
+        Value::Tuple(vs) => format!(
+            "({})",
+            vs.iter().map(pretty_value).collect::<Vec<_>>().join(", ")
+        ),
+        // Anything else (structs, ...): fall back to the default form.
+        other => other.to_string(),
+    }
+}
+
+fn main() {
+    env_logger::Builder::from_default_env()
+        .format_level(false)
+        .format_timestamp(None)
+        .init();
+
+    let options = Options::parse();
+    circ::cfg::set(&options.circ);
+
+    // The frontend panics on a missing file with an unhelpful unwrap
+    // message; check up front so the user gets a plain answer.
+    if !options.path.exists() {
+        eprintln!("Error: file not found: {}", options.path.display());
+        std::process::exit(1);
+    }
+
+    // Find every @test function and evaluate its annotation inputs to
+    // concrete values. Parse errors surface as panics, evaluation errors
+    // through the Result.
+    let tests = match catch(|| ZSharpCurlyFE::eval_test_inputs(options.path.clone(), Mode::Proof)) {
+        Ok(Ok(tests)) => tests,
+        Ok(Err(e)) | Err(e) => {
+            eprintln!("Error: {}", e);
+            std::process::exit(1);
+        }
+    };
+
+    println!(
+        "running {} test{} from {}",
+        tests.len(),
+        if tests.len() == 1 { "" } else { "s" },
+        options.path.display()
+    );
+
+    let (mut passed, mut failed, mut errored) = (0, 0, 0);
+    for t in &tests {
+        // Show each input as `name = <source> = <value>`, collapsing to
+        // `name = <value>` when the source is already just the value.
+        let inputs: Vec<String> = t
+            .inputs()
+            .iter()
+            .map(|input| {
+                let value = pretty_value(input.value());
+                if input.source() == value {
+                    format!("{} = {}", input.name(), value)
+                } else {
+                    format!("{} = {} = {}", input.name(), input.source(), value)
+                }
+            })
+            .collect();
+        print!(
+            "test {} [{}] ({}) ... ",
+            t.name(),
+            t.settings().backend(),
+            inputs.join(", ")
+        );
+        // Flush so the prover's own stderr diagnostics (printed when a
+        // constraint fails) appear under this test's line, not before it.
+        use std::io::Write;
+        let _ = std::io::stdout().flush();
+
+        let indent = |msg: String| {
+            // The prover's message spans several lines; indent them all.
+            for line in msg.lines() {
+                println!("    {}", line);
+            }
+        };
+        let outcome = match t.settings().backend() {
+            TestBackend::Groth16 => run_test::<Bellman<Bls12>>(t),
+            TestBackend::Mirage => run_test::<Mirage<Bls12>>(t),
+        };
+        match outcome {
+            Outcome::Pass => {
+                passed += 1;
+                println!("ok");
+            }
+            Outcome::AssertionFailed(msg) => {
+                failed += 1;
+                println!("FAILED");
+                indent(msg);
+            }
+            Outcome::CompileError(msg) | Outcome::BackendError(msg) => {
+                errored += 1;
+                println!("error");
+                indent(msg);
+            }
+        }
+    }
+
+    println!(
+        "\ntest result: {}. {} passed; {} failed; {} errored",
+        if failed == 0 && errored == 0 {
+            "ok"
+        } else {
+            "FAILED"
+        },
+        passed,
+        failed,
+        errored
+    );
+    if failed > 0 || errored > 0 {
+        std::process::exit(1);
+    }
+}