feat: Catch types in Cargo.toml and warn about them

Cargo.lock

@@ -756,6 +756,14 @@ dependencies = [
  "syn 0.15.18 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "serde_ignored"
+version = "0.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "serde_json"
 version = "1.0.32"
@@ -1056,6 +1064,7 @@ dependencies = [
  "parking_lot 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_ignored 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "siphasher 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "slog 2.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -1226,6 +1235,7 @@ dependencies = [
 "checksum semver-parser 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "388a1df253eca08550bef6c72392cfe7c30914bf41df5269b68cbd6ff8f570a3"
 "checksum serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)" = "15c141fc7027dd265a47c090bf864cf62b42c4d228bbcf4e51a0c9e2b0d3f7ef"
 "checksum serde_derive 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)" = "225de307c6302bec3898c51ca302fc94a7a1697ef0845fcee6448f33c032249c"
+"checksum serde_ignored 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "190e9765dcedb56be63b6e0993a006c7e3b071a016a304736e4a315dc01fb142"
 "checksum serde_json 1.0.32 (registry+https://github.com/rust-lang/crates.io-index)" = "43344e7ce05d0d8280c5940cabb4964bea626aa58b1ec0e8c73fa2a8512a38ce"
 "checksum siphasher 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "0b8de496cf83d4ed58b6be86c3a275b8602f6ffe98d3024a869e124147a9a3ac"
 "checksum slog 2.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "1e1a2eec401952cd7b12a84ea120e2d57281329940c3f93c2bf04f462539508e"

Cargo.toml

@@ -25,6 +25,7 @@ openssl = { version = '0.10.11', optional = true }
 parking_lot = "0.6"
 serde = "1.0.74"
 serde_derive = "1.0.74"
+serde_ignored = "0.0.4"
 serde_json = "1.0.26"
 siphasher = "0.2.3"
 slog = "2.3"

src/lib.rs

@@ -17,6 +17,7 @@ extern crate parking_lot;
 extern crate serde;
 #[macro_use]
 extern crate serde_derive;
+extern crate serde_ignored;
 extern crate serde_json;
 extern crate siphasher;
 #[macro_use]

src/manifest/mod.rs

@@ -15,6 +15,7 @@ use failure::{Error, ResultExt};
 use progressbar::Step;
 use serde::{self, Deserialize};
 use serde_json;
+use std::collections::BTreeSet;
 use toml;
 use PBAR;
 
@@ -210,8 +211,25 @@ impl CrateData {
         }
         let manifest = fs::read_to_string(&manifest_path)
             .with_context(|_| format!("failed to read: {}", manifest_path.display()))?;
-        let manifest: CargoManifest = toml::from_str(&manifest)
-            .with_context(|_| format!("failed to parse manifest: {}", manifest_path.display()))?;
+        let manifest = &mut toml::Deserializer::new(&manifest);
+
+        let mut unused_keys = BTreeSet::new();
+
+        let manifest: CargoManifest = serde_ignored::deserialize(manifest, |path| {
+            let path_string = path.to_string();
+
+            if path_string.contains("metadata") {
+                unused_keys.insert(path_string);
+            }
+        })
+        .with_context(|_| format!("failed to parse manifest: {}", manifest_path.display()))?;
+
+        unused_keys.iter().for_each(|path| {
+            PBAR.warn(&format!(
+                "\"{}\" is misspelled and will be ignored. Please check your Cargo.toml.",
+                path
+            ));
+        });
 
         let data =
             cargo_metadata::metadata(Some(&manifest_path)).map_err(error_chain_to_failure)?;