Add trivial fuzzer for parser

As described in #61, fuzz testing some parts of this would be ~~fun~~
helpful. So, I started with the most trivial fuzzer I could think of:
Put random stuff into File::parse and see what happens.

To speed things up, I also did

    cp src/**/*.rs fuzz/corpus/parser/

in the `crates/libsyntax2/` directory (running the fuzzer once will
generate the necessary directories).

1 files changed, 22 insertions, 0 deletions

diff --git a/crates/libsyntax2/fuzz/Cargo.toml b/crates/libsyntax2/fuzz/Cargo.toml
new file mode 100644
index 000000000..916cd5b6f
--- /dev/null
+++ b/crates/libsyntax2/fuzz/Cargo.toml
@@ -0,0 +1,22 @@
+
+[package]
+name = "libsyntax2-fuzz"
+version = "0.0.1"
+authors = ["Automatically generated"]
+publish = false
+
+[package.metadata]
+cargo-fuzz = true
+
+[dependencies.libsyntax2]
+path = ".."
+[dependencies.libfuzzer-sys]
+git = "https://github.com/rust-fuzz/libfuzzer-sys.git"
+
+# Prevent this from interfering with workspaces
+[workspace]
+members = ["."]
+
+[[bin]]
+name = "parser"
+path = "fuzz_targets/parser.rs"