refactor: create submodules for tests

src/nodes/eval.rs

@@ -28,8 +28,8 @@ impl Nodes {
         let len = nodes.len();
         collapse_toplevel(nodes, len)?;
 
-        match nodes.pop().unwrap() {
-            Node::Number(n) => Ok(n),
+        match nodes.pop() {
+            Some(Node::Number(n)) => Ok(n),
             _ => Err(Error::CollapseFailed(self)),
         }
     }
@@ -41,7 +41,7 @@ fn collapse_toplevel(nodes: &mut Vec<Node>, mut end: usize) -> Result<(), Error>
         .rposition(|n| *n == Node::ParenthesisStart)
         .unwrap_or(0);
 
-    while let Some((index, variant)) = nodes[start..end]
+    while let Some((index, function)) = nodes[start..end]
         .iter()
         .enumerate()
         .filter_map(|(i, n)| match n {
@@ -58,20 +58,7 @@ fn collapse_toplevel(nodes: &mut Vec<Node>, mut end: usize) -> Result<(), Error>
             return Err(Error::MissingArgument(node.clone()));
         };
 
-        match variant {
-            Function::Sqrt => n.sqrt_mut(),
-
-            Function::Ln => n.ln_mut(),
-
-            Function::Sine => n.sin_mut(),
-            Function::ArcSine => n.asin_mut(),
-            Function::Cosine => n.cos_mut(),
-            Function::ArcCosine => n.acos_mut(),
-            Function::Tangent => n.tan_mut(),
-            Function::ArcTangent => n.atan_mut(),
-            Function::Secant => n.sec_mut(),
-            Function::CoSecant => n.csc_mut(),
-        };
+        function.for_float()(n);
 
         nodes.remove(start + index);
         end -= 1;
@@ -185,23 +172,54 @@ fn collapse_toplevel(nodes: &mut Vec<Node>, mut end: usize) -> Result<(), Error>
     Ok(())
 }
 
-#[cfg(test)]
-use super::PREC;
+impl Function {
+    fn for_float(&self) -> impl FnMut(&mut Float) {
+        match self {
+            Function::Sqrt => Float::sqrt_mut,
 
-#[test]
-fn test() {
-    assert_eq!(
-        Nodes(vec![
-            Node::Function(Function::Sine),
-            Node::ParenthesisStart,
-            Node::Number(Float::with_val(PREC, 2)),
-            Node::ParenthesisEnd,
-            Node::Operator(Operator::Plus),
-            Node::Number(Float::with_val(PREC, 1))
-        ])
-        .evaluate()
-        .unwrap()
-        .to_f64(),
-        1.9092974268256817,
-    );
+            Function::Ln => Float::ln_mut,
+
+            Function::Sine => Float::sin_mut,
+            Function::ArcSine => Float::asin_mut,
+            Function::Cosine => Float::cos_mut,
+            Function::ArcCosine => Float::acos_mut,
+            Function::Tangent => Float::tan_mut,
+            Function::ArcTangent => Float::atan_mut,
+            Function::Secant => Float::sec_mut,
+            Function::CoSecant => Float::csc_mut,
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::super::PREC;
+    use super::*;
+    use std::assert_matches;
+
+    #[test]
+    fn basic() {
+        assert_eq!(
+            Nodes(vec![
+                Node::Function(Function::Sine),
+                Node::ParenthesisStart,
+                Node::Number(Float::with_val(PREC, 2)),
+                Node::ParenthesisEnd,
+                Node::Operator(Operator::Plus),
+                Node::Number(Float::with_val(PREC, 1))
+            ])
+            .evaluate()
+            .unwrap()
+            .to_f64(),
+            1.9092974268256817,
+        );
+    }
+
+    #[test]
+    fn zerosized() {
+        assert_matches!(
+            Nodes(vec![Node::ParenthesisStart, Node::ParenthesisEnd]).evaluate(),
+            Err(Error::CollapseFailed(Nodes(v))) if v.is_empty()
+        )
+    }
 }

src/nodes/parse.rs

@@ -195,43 +195,49 @@ impl FromStr for Nodes {
     }
 }
 
-#[test]
-fn test() {
-    assert_eq!(
-        Nodes::from_str("sin(2) + 1").unwrap().as_ref(),
-        &[
-            Node::Function(Function::Sine),
-            Node::ParenthesisStart,
-            Node::from(2),
-            Node::ParenthesisEnd,
-            Node::Operator(Operator::Plus),
-            Node::from(1),
-        ],
-    )
-}
-#[test]
-fn test_e() {
-    assert_eq!(
-        Nodes::from_str("5e * 5").unwrap().as_ref(),
-        &[
-            Node::from(5),
-            Node::Operator(Operator::Mult),
-            Node::from(f64::consts::E),
-            Node::Operator(Operator::Mult),
-            Node::from(5),
-        ],
-    )
-}
-#[test]
-fn test_unary_op() {
-    assert_eq!(
-        Nodes::from_str("5(-5)").unwrap().as_ref(),
-        &[
-            Node::from(5),
-            Node::Operator(Operator::Mult),
-            Node::ParenthesisStart,
-            Node::from(-5),
-            Node::ParenthesisEnd,
-        ],
-    )
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn basic() {
+        assert_eq!(
+            Nodes::from_str("sin(2) + 1").unwrap().as_ref(),
+            &[
+                Node::Function(Function::Sine),
+                Node::ParenthesisStart,
+                Node::from(2),
+                Node::ParenthesisEnd,
+                Node::Operator(Operator::Plus),
+                Node::from(1),
+            ],
+        )
+    }
+
+    #[test]
+    fn e_constant() {
+        assert_eq!(
+            Nodes::from_str("5e * 5").unwrap().as_ref(),
+            &[
+                Node::from(5),
+                Node::Operator(Operator::Mult),
+                Node::from(f64::consts::E),
+                Node::Operator(Operator::Mult),
+                Node::from(5),
+            ],
+        )
+    }
+    #[test]
+    fn unary_op() {
+        assert_eq!(
+            Nodes::from_str("5(-5)").unwrap().as_ref(),
+            &[
+                Node::from(5),
+                Node::Operator(Operator::Mult),
+                Node::ParenthesisStart,
+                Node::from(-5),
+                Node::ParenthesisEnd,
+            ],
+        )
+    }
 }