put helpers in folder, add libsnark flags

zokrates_core/src/flat_absy/mod.rs

@@ -14,6 +14,7 @@ use std::fmt;
 use std::collections::{BTreeMap};
 use field::Field;
 use substitution::Substitution;
+#[cfg(feature = "libsnark")]
 use standard;
 use helpers::{DirectiveStatement, Executable};
 
@@ -61,6 +62,7 @@ impl<T: Field> fmt::Debug for FlatProg<T> {
     }
 }
 
+#[cfg(feature = "libsnark")]
 impl<T: Field> From<standard::R1CS> for FlatProg<T> {
     fn from(r1cs: standard::R1CS) -> Self {
         FlatProg {

zokrates_core/src/helpers/libsnark_gadget.rs

@@ -0,0 +1,43 @@
+use libsnark::get_sha256_witness;
+use serde_json;
+use standard;
+use std::fmt;
+use field::{Field};
+use helpers::{Signed, Executable};
+
+#[derive(Clone, PartialEq, Debug, Serialize, Deserialize)]
+pub enum LibsnarkGadgetHelper {
+	Sha256Compress,
+}
+
+impl fmt::Display for LibsnarkGadgetHelper {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    	match *self {
+    		LibsnarkGadgetHelper::Sha256Compress => write!(f, "Sha256Compress"),
+    	}
+    }
+}
+
+impl<T: Field> Executable<T> for LibsnarkGadgetHelper {
+	fn execute(&self, inputs: &Vec<T>) -> Result<Vec<T>, String> {
+		match self {
+			LibsnarkGadgetHelper::Sha256Compress => {
+				let witness_result: Result<standard::Witness, serde_json::Error> = serde_json::from_str(&get_sha256_witness(inputs));
+
+				if let Err(e) = witness_result {
+					return Err(format!("{}", e));
+				}
+
+				Ok(witness_result.unwrap().variables.iter().map(|&i| T::from(i)).collect())
+			},
+		}
+	}
+}
+
+impl Signed for LibsnarkGadgetHelper {
+	fn get_signature(&self) -> (usize, usize) {
+		match self {
+			LibsnarkGadgetHelper::Sha256Compress => (512, 25561),
+		}
+	}
+}

zokrates_core/src/helpers/mod.rs

@@ -1,7 +1,13 @@
+#[cfg(feature = "libsnark")]
+mod libsnark_gadget;
+mod rust;
+
+#[cfg(feature = "libsnark")]
+pub use self::libsnark_gadget::LibsnarkGadgetHelper;
+pub use self::rust::RustHelper;
 use std::fmt;
 use field::{Field};
-use serde_json;
-use standard;
+
 
 #[derive(Clone, PartialEq, Debug, Serialize, Deserialize)]
 pub struct DirectiveStatement {
@@ -18,6 +24,7 @@ impl fmt::Display for DirectiveStatement {
 
 #[derive(Clone, PartialEq, Debug, Serialize, Deserialize)]
 pub enum Helper {
+	#[cfg(feature = "libsnark")]
 	LibsnarkGadget(LibsnarkGadgetHelper),
 	Rust(RustHelper)
 }
@@ -25,40 +32,13 @@ pub enum Helper {
 impl fmt::Display for Helper {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
     	match *self {
+    		#[cfg(feature = "libsnark")]
     		Helper::LibsnarkGadget(ref h) => write!(f, "LibsnarkGadget::{}", h),
     		Helper::Rust(ref h) => write!(f, "Rust::{}", h)
     	}
     }
 }
 
-#[derive(Clone, PartialEq, Debug, Serialize, Deserialize)]
-pub enum LibsnarkGadgetHelper {
-	Sha256Compress,
-}
-
-impl fmt::Display for LibsnarkGadgetHelper {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    	match *self {
-    		LibsnarkGadgetHelper::Sha256Compress => write!(f, "Sha256Compress"),
-    	}
-    }
-}
-
-#[derive(Clone, PartialEq, Debug, Serialize, Deserialize)]
-pub enum RustHelper {
-	Identity,
-	ConditionEq,
-}
-
-impl fmt::Display for RustHelper {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-    	match *self {
-    		RustHelper::Identity => write!(f, "Identity"),
-    		RustHelper::ConditionEq => write!(f, "ConditionEq"),
-    	}
-    }
-}
-
 pub trait Executable<T: Field>
 	: Signed {
 	fn execute(&self, inputs: &Vec<T>) -> Result<Vec<T>, String>;
@@ -68,69 +48,13 @@ pub trait Signed {
 	fn get_signature(&self) -> (usize, usize);
 }
 
-impl<T: Field> Executable<T> for LibsnarkGadgetHelper {
-	fn execute(&self, inputs: &Vec<T>) -> Result<Vec<T>, String> {
-		match self {
-			LibsnarkGadgetHelper::Sha256Compress => {
-				#[cfg(not(feature = "libsnark"))]
-				{
-					Err(format!("Libsnark is not available"))
-				}
-
-				#[cfg(feature = "libsnark")]
-				{
-					use libsnark::*;
-
-					let witness_result: Result<standard::Witness, serde_json::Error> = serde_json::from_str(&get_sha256_witness(inputs));
-
-					if let Err(e) = witness_result {
-						return Err(format!("{}", e));
-					}
-
-					Ok(witness_result.unwrap().variables.iter().map(|&i| T::from(i)).collect())
-				}
-			},
-		}
-	}
-}
-
-impl Signed for LibsnarkGadgetHelper {
-	fn get_signature(&self) -> (usize, usize) {
-		match self {
-			LibsnarkGadgetHelper::Sha256Compress => (512, 25561),
-		}
-	}
-}
-
-impl<T: Field> Executable<T> for RustHelper {
-	fn execute(&self, inputs: &Vec<T>) -> Result<Vec<T>, String> {
-		match self {
-			RustHelper::Identity => Ok(inputs.clone()),
-			RustHelper::ConditionEq => {
-				match inputs[0].is_zero() {
-					true => Ok(vec![T::zero(), T::one()]),
-					false => Ok(vec![T::one(), T::one() / inputs[0].clone()])
-				}
-			},
-		}
-	}
-}
-
-impl Signed for RustHelper {
-	fn get_signature(&self) -> (usize, usize) {
-		match self {
-			RustHelper::Identity => (1, 1),
-			RustHelper::ConditionEq => (1, 2),
-		}
-	}
-}
-
 impl<T: Field> Executable<T> for Helper {
 	fn execute(&self, inputs: &Vec<T>) -> Result<Vec<T>, String> {
 		let (expected_input_count, expected_output_count) = self.get_signature();
 		assert!(inputs.len() == expected_input_count);
 
 		let result = match self {
+			#[cfg(feature = "libsnark")]
 			Helper::LibsnarkGadget(helper) => helper.execute(inputs),
 			Helper::Rust(helper) => helper.execute(inputs)
 		};
@@ -145,6 +69,7 @@ impl<T: Field> Executable<T> for Helper {
 impl Signed for Helper {
 	fn get_signature(&self) -> (usize, usize) {
 		match self {
+			#[cfg(feature = "libsnark")]
 			Helper::LibsnarkGadget(helper) => helper.get_signature(),
 			Helper::Rust(helper) => helper.get_signature()
 		}
@@ -161,7 +86,6 @@ mod tests {
 		use super::*;
 
 		#[test]
-		#[cfg(not(feature = "nolibsnark"))]
 		fn execute() {
 			let sha = LibsnarkGadgetHelper::Sha256Compress;
 			// second vector here https://homes.esat.kuleuven.be/~nsmart/MPC/sha-256-test.txt

zokrates_core/src/helpers/rust.rs

@@ -0,0 +1,42 @@
+use std::fmt;
+use helpers::{Signed, Executable};
+use field::{Field};
+
+#[derive(Clone, PartialEq, Debug, Serialize, Deserialize)]
+pub enum RustHelper {
+	Identity,
+	ConditionEq,
+}
+
+impl fmt::Display for RustHelper {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    	match *self {
+    		RustHelper::Identity => write!(f, "Identity"),
+    		RustHelper::ConditionEq => write!(f, "ConditionEq"),
+    	}
+    }
+}
+
+impl Signed for RustHelper {
+	fn get_signature(&self) -> (usize, usize) {
+		match self {
+			RustHelper::Identity => (1, 1),
+			RustHelper::ConditionEq => (1, 2),
+		}
+	}
+}
+
+
+impl<T: Field> Executable<T> for RustHelper {
+	fn execute(&self, inputs: &Vec<T>) -> Result<Vec<T>, String> {
+		match self {
+			RustHelper::Identity => Ok(inputs.clone()),
+			RustHelper::ConditionEq => {
+				match inputs[0].is_zero() {
+					true => Ok(vec![T::zero(), T::one()]),
+					false => Ok(vec![T::one(), T::one() / inputs[0].clone()])
+				}
+			},
+		}
+	}
+}

zokrates_core/src/lib.rs

@@ -17,6 +17,7 @@ mod semantics;
 mod substitution;
 mod flatten;
 mod optimizer;
+#[cfg(feature = "libsnark")]
 mod standard;
 mod helpers;
 mod types;