add common crate

Signed-off-by: xermicus <cyrill@parity.io>

crates/common/src/utils.rs

@@ -0,0 +1,35 @@
+//!
+//! The compiler common utils.
+//!
+
+///
+/// Deserializes a `serde_json` object from slice with the recursion limit disabled.
+///
+/// Must be used for all JSON I/O to avoid crashes due to the aforementioned limit.
+///
+pub fn deserialize_from_slice<O>(input: &[u8]) -> anyhow::Result<O>
+where
+    O: serde::de::DeserializeOwned,
+{
+    let mut deserializer = serde_json::Deserializer::from_slice(input);
+    deserializer.disable_recursion_limit();
+    let deserializer = serde_stacker::Deserializer::new(&mut deserializer);
+    let result = O::deserialize(deserializer)?;
+    Ok(result)
+}
+
+///
+/// Deserializes a `serde_json` object from string with the recursion limit disabled.
+///
+/// Must be used for all JSON I/O to avoid crashes due to the aforementioned limit.
+///
+pub fn deserialize_from_str<O>(input: &str) -> anyhow::Result<O>
+where
+    O: serde::de::DeserializeOwned,
+{
+    let mut deserializer = serde_json::Deserializer::from_str(input);
+    deserializer.disable_recursion_limit();
+    let deserializer = serde_stacker::Deserializer::new(&mut deserializer);
+    let result = O::deserialize(deserializer)?;
+    Ok(result)
+}