Add structopt dependency in version 0.3.7

This patch series replaces argparse with structopt in the argument
handling code. As a first step, we need structopt as a dependency.

Import subrepo structopt/:structopt at efbdda4753592e27bc430fb01f7b9650b2f3174d
Import subrepo bitflags/:bitflags at 30668016aca6bd3b02c766e8347e0b4080d4c296
Import subrepo clap/:clap at 784524f7eb193e35f81082cc69454c8c21b948f7
Import subrepo heck/:heck at 093d56fbf001e1506e56dbfa38631d99b1066df1
Import subrepo proc-macro-error/:proc-macro-error at 6c4cfe79a622c5de8ae68557993542be46eacae2
Import subrepo proc-macro2/:proc-macro2 at d5d48eddca4566e5438e8a2cbed4a74e049544de
Import subrepo quote/:quote at 727436c6c137b20f0f34dde5d8fda2679b9747ad
Import subrepo rustversion/:rustversion at 0c5663313516263059ce9059ef81fc7a1cf655ca
Import subrepo syn-mid/:syn-mid at 5d3d85414a9e6674e1857ec22a87b96e04a6851a
Import subrepo syn/:syn at e87c27e87f6f4ef8919d0372bdb056d53ef0d8f3
Import subrepo textwrap/:textwrap at abcd618beae3f74841032aa5b53c1086b0a57ca2
Import subrepo unicode-segmentation/:unicode-segmentation at 637c9874c4fe0c205ff27787faf150a40295c6c3
Import subrepo unicode-width/:unicode-width at 3033826f8bf05e82724140a981d5941e48fce393
Import subrepo unicode-xid/:unicode-xid at 4baae9fffb156ba229665b972a9cd5991787ceb7

4 files changed, 50 insertions, 0 deletions

diff --git a/syn/dev/Cargo.toml b/syn/dev/Cargo.toml
new file mode 100644
index 0000000..79486c1
--- /dev/null
+++ b/syn/dev/Cargo.toml
@@ -0,0 +1,22 @@
+[package]
+name = "syn-dev"
+version = "0.0.0"
+authors = ["David Tolnay <dtolnay@gmail.com>"]
+edition = "2018"
+publish = false
+
+[lib]
+path = "parse.rs"
+proc-macro = true
+
+[[bin]]
+path = "main.rs"
+name = "syn-dev"
+
+[dependencies]
+quote = "1.0"
+
+[dependencies.syn]
+path = ".."
+default-features = false
+features = ["parsing", "full", "extra-traits", "proc-macro"]
diff --git a/syn/dev/README.md b/syn/dev/README.md
new file mode 100644
index 0000000..91b9846
--- /dev/null
+++ b/syn/dev/README.md
@@ -0,0 +1,6 @@
+A little project skeleton for troubleshooting Syn's parsers during development,
+especially when adding support for new Rust syntax.
+
+Place a sample of the syntax you are working on into main.rs and then run `cargo
+check` to try parsing it, revealing the resulting syntax tree or else showing
+the position and error message if the input fails to parse.
diff --git a/syn/dev/main.rs b/syn/dev/main.rs
new file mode 100644
index 0000000..eb67546
--- /dev/null
+++ b/syn/dev/main.rs
@@ -0,0 +1,4 @@
+syn_dev::r#mod! {
+    // Write Rust code here and run `cargo check` to have Syn parse it.
+
+}
diff --git a/syn/dev/parse.rs b/syn/dev/parse.rs
new file mode 100644
index 0000000..2a92550
--- /dev/null
+++ b/syn/dev/parse.rs
@@ -0,0 +1,18 @@
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::File;
+
+#[proc_macro]
+pub fn r#mod(input: TokenStream) -> TokenStream {
+    let compile_error = syn::parse::<File>(input)
+        .map(|file| println!("{:#?}", file))
+        .map_err(|err| err.to_compile_error())
+        .err();
+
+    TokenStream::from(quote! {
+        #compile_error
+        fn main() {}
+    })
+}