Move inherents to primitives (#4126)

* Split Aura and Timestamp inherents out of paint

* fixup node depedencies

* move babe inherents to primitives

* move authorship inherents into primitives

* Move finalty tracker inherents into primitives

* fix aura primitives import

substrate/primitives/consensus/babe/src/inherents.rs

@@ -0,0 +1,90 @@
+// Copyright 2019 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Substrate is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+//! Inherents for BABE
+
+use sp_inherents::{Error, InherentData, InherentIdentifier};
+#[cfg(feature = "std")]
+use sp_inherents::{InherentDataProviders, ProvideInherentData};
+#[cfg(feature = "std")]
+use sp_timestamp::TimestampInherentData;
+
+#[cfg(feature = "std")]
+use codec::Decode;
+use rstd::result::Result;
+
+/// The BABE inherent identifier.
+pub const INHERENT_IDENTIFIER: InherentIdentifier = *b"babeslot";
+
+/// The type of the BABE inherent.
+pub type InherentType = u64;
+/// Auxiliary trait to extract BABE inherent data.
+pub trait BabeInherentData {
+    /// Get BABE inherent data.
+    fn babe_inherent_data(&self) -> Result<InherentType, Error>;
+    /// Replace BABE inherent data.
+    fn babe_replace_inherent_data(&mut self, new: InherentType);
+}
+
+impl BabeInherentData for InherentData {
+    fn babe_inherent_data(&self) -> Result<InherentType, Error> {
+        self.get_data(&INHERENT_IDENTIFIER)
+            .and_then(|r| r.ok_or_else(|| "BABE inherent data not found".into()))
+    }
+
+    fn babe_replace_inherent_data(&mut self, new: InherentType) {
+        self.replace_data(INHERENT_IDENTIFIER, &new);
+    }
+}
+
+/// Provides the slot duration inherent data for BABE.
+#[cfg(feature = "std")]
+pub struct InherentDataProvider {
+    slot_duration: u64,
+}
+
+#[cfg(feature = "std")]
+impl InherentDataProvider {
+    /// Constructs `Self`
+    pub fn new(slot_duration: u64) -> Self {
+        Self { slot_duration }
+    }
+}
+
+#[cfg(feature = "std")]
+impl ProvideInherentData for InherentDataProvider {
+    fn on_register(&self, providers: &InherentDataProviders) -> Result<(), Error> {
+        if !providers.has_provider(&sp_timestamp::INHERENT_IDENTIFIER) {
+            // Add the timestamp inherent data provider, as we require it.
+            providers.register_provider(sp_timestamp::InherentDataProvider)
+        } else {
+            Ok(())
+        }
+    }
+
+    fn inherent_identifier(&self) -> &'static InherentIdentifier {
+        &INHERENT_IDENTIFIER
+    }
+
+    fn provide_inherent_data(&self, inherent_data: &mut InherentData) -> Result<(), Error> {
+        let timestamp = inherent_data.timestamp_inherent_data()?;
+        let slot_number = timestamp / self.slot_duration;
+        inherent_data.put_data(INHERENT_IDENTIFIER, &slot_number)
+    }
+
+    fn error_to_string(&self, error: &[u8]) -> Option<String> {
+        Error::decode(&mut &error[..]).map(|e| e.into_string()).ok()
+    }
+}

substrate/primitives/consensus/babe/src/lib.rs

@@ -20,6 +20,7 @@
 #![cfg_attr(not(feature = "std"), no_std)]
 
 mod digest;
+pub mod inherents;
 
 use codec::{Encode, Decode};
 use rstd::vec::Vec;