Fix tests to run on stable

Signed-off-by: trivernis <trivernis@protonmail.com>

Cargo.toml

@@ -2,7 +2,7 @@
 name = "asciimath-rs"
 description = "AsciiMath parser"
 repository = "https://github.com/trivernis/asciimath-rs"
-version = "0.5.6"
+version = "0.5.7"
 authors = ["trivernis <trivernis@protonmail.com>"]
 edition = "2018"
 readme = "README.md"
@@ -13,7 +13,7 @@ categories = ["mathematics", "parser-implementations"]
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-charred = "0.3.1"
+charred = "0.3.3"
 maplit = "1.0.2"
 lazy_static = "1.4.0"
 htmlescape = "0.3.1"

src/lib.rs

@@ -1,6 +1,3 @@
-#![feature(test)]
-extern crate test;
-
 #[macro_use]
 extern crate maplit;
 
@@ -51,7 +48,6 @@ mod tests {
     use crate::tokens::{Function, Grouping, Misc, Operation, Relation, Text, Token};
     use crate::utils::Boxed;
     use std::fs;
-    use test::Bencher;
 
     #[test]
     fn it_tokenizes_expressions1() {
@@ -399,10 +395,4 @@ mod tests {
         )
         .unwrap();
     }
-
-    #[bench]
-    fn bench_tokenizer(b: &mut Bencher) {
-        let expression = "sqrt 1 in NN implies 2^4 + sum_(k = 1)^3 - ((1),(2)) [[2, 3 + 3],[4, 5]] (((((((nesting)))))))";
-        b.iter(|| parse(expression.to_string()));
-    }
 }

src/parsing/tree_parser.rs

@@ -460,7 +460,7 @@ impl TreeParser {
             self.step();
             Some(Frac {
                 top: previous.to_non_enclosed().boxed(),
-                bottom: self.parse_element().unwrap().to_non_enclosed().boxed(),
+                bottom: self.parse_element()?.to_non_enclosed().boxed(),
             })
         } else {
             None