Fix default feature for tests

Also add an example for creating a circuit.

.github/workflows/dusk_ci.yml

@@ -25,6 +25,14 @@ jobs:
       - uses: Swatinem/rust-cache@v2
       - run: cargo bench --no-run
 
+  run_examples:
+    name: Run Examples
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: Swatinem/rust-cache@v2
+      - run: cargo run --release --example circuit
+
   build_docs:
     name: Build Documentation
     runs-on: ubuntu-latest

Cargo.toml

@@ -42,10 +42,6 @@ tempdir = "0.3"
 rand = "0.8"
 rkyv = {version = "0.7", default-features = false, features = ["size_32"]}
 
-[[bench]]
-name = "plonk"
-harness = false
-
 [features]
 default = ["std"]
 std = [
@@ -78,9 +74,69 @@ lto = true
 incremental = false
 codegen-units = 1
 
+[[example]]
+name = "circuit"
+required-features = ["alloc"]
+
+[[bench]]
+name = "plonk"
+harness = false
+
+[[test]]
+name = "append_gate"
+required-features = ["alloc"]
+
+[[test]]
+name = "assert_point"
+required-features = ["alloc"]
+
+[[test]]
+name = "assert_scalar"
+required-features = ["alloc"]
+
+[[test]]
+name = "boolean"
+required-features = ["alloc"]
+
+[[test]]
+name = "composer"
+required-features = ["alloc"]
+
 [[test]]
 name = "debugger"
 required-features = ["debug", "std"]
 
+[[test]]
+name = "decomposition"
+required-features = ["alloc"]
+
+[[test]]
+name = "ecc"
+required-features = ["alloc"]
+
+[[test]]
+name = "error_size"
+required-features = ["alloc"]
+
+[[test]]
+name = "gate_add_mul"
+required-features = ["alloc"]
+
+[[test]]
+name = "logic"
+required-features = ["alloc"]
+
+[[test]]
+name = "range"
+required-features = ["alloc"]
+
+[[test]]
+name = "select_bls"
+required-features = ["alloc"]
+
+[[test]]
+name = "select_point"
+required-features = ["alloc"]
+
 [package.metadata.docs.rs]
 rustdoc-args = [ "--html-in-header", "./docs/katex-header.html" ]

README.md

@@ -15,78 +15,7 @@ an exhaustive security analysis. Use at your own risk.
 
 ## Usage
 
-```rust
-use dusk_plonk::prelude::*;
-use rand_core::OsRng;
-
-// Implement a circuit that checks:
-// 1) a + b = c where C is a PI
-// 2) a < 2^6
-// 3) b < 2^4
-// 4) a * b = d where D is a PI
-// 5) JubJub::GENERATOR * e(JubJubScalar) = f where F is a Public Input
-#[derive(Debug, Default)]
-pub struct TestCircuit {
-    a: BlsScalar,
-    b: BlsScalar,
-    c: BlsScalar,
-    d: BlsScalar,
-    e: JubJubScalar,
-    f: JubJubAffine,
-}
-
-impl Circuit for TestCircuit {
-    fn circuit(&self, composer: &mut Composer) -> Result<(), Error>
-    {
-        let a = composer.append_witness(self.a);
-        let b = composer.append_witness(self.b);
-
-        // Make first constraint a + b = c
-        let constraint =
-            Constraint::new().left(1).right(1).public(-self.c).a(a).b(b);
-
-        composer.append_gate(constraint);
-
-        // Check that a and b are in range
-        const HALF_SIX: usize = 3;
-        composer.component_range::<HALF_SIX>(a);
-        const HALF_FOUR: usize = 2;
-        composer.component_range::<HALF_FOUR>(b);
-
-        // Make second constraint a * b = d
-        let constraint =
-            Constraint::new().mult(1).public(-self.d).a(a).b(b);
-
-        composer.append_gate(constraint);
-
-        let e = composer.append_witness(self.e);
-        let scalar_mul_result = composer
-            .component_mul_generator(e, dusk_jubjub::GENERATOR_EXTENDED)?;
-
-        // Apply the constraint
-        composer.assert_equal_public_point(scalar_mul_result, self.f);
-
-        Ok(())
-    }
-}
-
-let label = b"transcript-arguments";
-let pp = PublicParameters::setup(1 << 12, &mut OsRng)
-    .expect("failed to setup");
-
-let (prover, verifier) = Compiler::compile::<TestCircuit>(&pp, label)
-    .expect("failed to compile circuit");
-
-// Generate the proof and its public inputs
-let (proof, public_inputs) = prover
-    .prove(&mut OsRng, &TestCircuit::default())
-    .expect("failed to prove");
-
-// Verify the generated proof
-verifier
-    .verify(&proof, &public_inputs)
-    .expect("failed to verify proof");
-```
+Check the 'examples' directory for the usage.
 
 ### Features
 

examples/circuit.rs

@@ -0,0 +1,95 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+//
+// Copyright (c) DUSK NETWORK. All rights reserved.
+
+use dusk_plonk::prelude::*;
+use rand_core::OsRng;
+
+// Create a `TestCircuit` struct.
+#[derive(Debug, Default)]
+pub struct TestCircuit {
+    pub a: BlsScalar,
+    pub b: BlsScalar,
+    pub c: BlsScalar,
+    pub d: BlsScalar,
+    pub e: JubJubScalar,
+    pub f: JubJubAffine,
+}
+
+// Implement the 'Circuit' trait that checks:
+// 1) a < 2^6
+// 2) b < 2^4
+// 3) a + b + 42 = c where c is public input
+// 4) a * b + d = 42
+// 5) JubJub::GENERATOR * e(JubJubScalar) = f where F is a Public Input
+impl Circuit for TestCircuit {
+    fn circuit(&self, composer: &mut Composer) -> Result<(), Error> {
+        let a = composer.append_witness(self.a);
+        let b = composer.append_witness(self.b);
+        let d = composer.append_witness(self.d);
+
+        // 1) a < 2^6
+        const HALF_SIX: usize = 3;
+        composer.component_range::<HALF_SIX>(a);
+
+        // 2) b < 2^4
+        const HALF_FOUR: usize = 2;
+        composer.component_range::<HALF_FOUR>(b);
+
+        // 3) a + b + 42 = c where c is public input
+        let constraint = Constraint::new()
+            .left(1)
+            .right(1)
+            .a(a)
+            .b(b)
+            .constant(BlsScalar::from(42));
+        let result = composer.gate_add(constraint);
+        let c = composer.append_public(self.c);
+        composer.assert_equal(result, c);
+
+        // 4) a * b + d = 42
+        let constraint = Constraint::new().mult(1).a(a).b(b).fourth(1).d(d);
+        let result = composer.gate_mul(constraint);
+        composer.assert_equal_constant(result, BlsScalar::from(42), None);
+
+        // 5) JubJub::GENERATOR * e(JubJubScalar) = f where F is a Public Input
+        let e = composer.append_witness(self.e);
+        let scalar_mul_result = composer
+            .component_mul_generator(e, dusk_jubjub::GENERATOR_EXTENDED)?;
+        composer.assert_equal_public_point(scalar_mul_result, self.f);
+
+        Ok(())
+    }
+}
+
+fn main() {
+    let label = b"transcript-arguments";
+    let pp =
+        PublicParameters::setup(1 << 12, &mut OsRng).expect("failed to setup");
+
+    // Compile the default circuit to generate prover and verifier
+    let (prover, verifier) = Compiler::compile::<TestCircuit>(&pp, label)
+        .expect("failed to compile circuit");
+
+    // Create the circuit and public inputs to prove
+    let a = BlsScalar::from(31);
+    let b = BlsScalar::zero();
+    let c = BlsScalar::from(73);
+    let d = BlsScalar::from(42);
+    let e = JubJubScalar::one();
+    let f: JubJubAffine = dusk_jubjub::GENERATOR_EXTENDED.into();
+    let circuit = TestCircuit { a, b, c, d, e, f };
+    let public_inputs = vec![c, f.get_u(), f.get_v()];
+
+    // Generate the proof and its public inputs
+    let (proof, pi) =
+        prover.prove(&mut OsRng, &circuit).expect("failed to prove");
+    assert_eq!(public_inputs, pi);
+
+    // Verify the generated proof
+    verifier
+        .verify(&proof, &public_inputs)
+        .expect("failed to verify proof");
+}

src/fft/domain.rs

@@ -322,12 +322,10 @@ pub(crate) mod alloc {
         }
     }
 
-    #[cfg(feature = "alloc")]
     fn best_fft(a: &mut [BlsScalar], omega: BlsScalar, log_n: u32) {
         serial_fft(a, omega, log_n)
     }
 
-    #[cfg(feature = "alloc")]
     #[inline]
     fn bitreverse(mut n: u32, l: u32) -> u32 {
         let mut r = 0;
@@ -338,7 +336,6 @@ pub(crate) mod alloc {
         r
     }
 
-    #[cfg(feature = "alloc")]
     pub(crate) fn serial_fft(
         a: &mut [BlsScalar],
         omega: BlsScalar,
@@ -402,6 +399,7 @@ pub(crate) mod alloc {
 }
 
 #[cfg(test)]
+#[cfg(feature = "alloc")]
 mod tests {
     use super::*;
 

tests/common/mod.rs

@@ -4,6 +4,8 @@
 //
 // Copyright (c) DUSK NETWORK. All rights reserved.
 
+#![cfg(feature = "default")]
+
 use dusk_plonk::prelude::*;
 use rand::{CryptoRng, RngCore};