Improve benchmarks

Author: orf

Cargo.toml

@@ -46,10 +46,6 @@ rustyline = "6.0"
 cpython = "0.5.0"
 criterion = "0.3"
 
-[[bench]]
-name = "parsing"
-harness = false
-
 [[bench]]
 name = "execution"
 harness = false

benches/README.md

@@ -4,26 +4,27 @@ These are some files to determine performance of rustpython.
 
 ## Usage
 
-Install pytest and pytest-benchmark:
+Running `cargo bench` from the root of the repository will start the benchmarks. Once done there will be a graphical 
+report under `target/critierion/report/index.html` that you can use use to view the results.
 
-    $ pip install pytest-benchmark
+To view Python tracebacks during benchmarks, run `RUST_BACKTRACE=1 cargo bench`. You can also bench against a 
+specific installed Python version by running:
 
-Then run:
+```shell
+$ PYTHON_SYS_EXECUTABLE=python3.7 cargo bench
+```
 
-    $ pytest
+### Adding a benchmark
 
-You can also benchmark the Rust benchmarks by just running
-`cargo bench` from the root of the repository. To view Python tracebacks during benchmarks,
-run `RUST_BACKTRACE=1 cargo bench`.
+Simply adding a file to the `benchmarks/` directory will add it to the set of files benchmarked. Each file is tested 
+in two ways:
 
-You can bench against a specific Python version by running:
+1. The time to parse the file to AST
+2. The time it takes to execute the file
 
-```shell
-$ PYTHON_SYS_EXECUTABLE=python3.7 cargo bench
-```
+## MacOS setup 
 
-On MacOS you will need to
-add the following to a `.cargo/config` file:
+On MacOS you will need to add the following to a `.cargo/config` file:
 
 ```toml
 [target.x86_64-apple-darwin]