Auto merge of #6451 - dwijnand:reify-DepFingerprint, r=alexcrichton

Reify the DepFingerprint type

I'm very slightly concerned I might've incompatibly changed the serialise/deserialise code with respect to existing serialised data, so please double-check my work.

src/cargo/core/compiler/fingerprint.rs

@@ -132,7 +132,11 @@ pub fn prepare_target<'a, 'cfg>(
 /// * its package id
 /// * its extern crate name
 /// * its calculated fingerprint for the dependency
-type DepFingerprint = (String, String, Arc<Fingerprint>);
+struct DepFingerprint {
+ pkg_id: String,
+ name: String,
+ fingerprint: Arc<Fingerprint>,
+}
 
 /// A fingerprint can be considered to be a "short string" representing the
 /// state of a world for a package.
@@ -162,10 +166,6 @@ pub struct Fingerprint {
  target: u64,
  profile: u64,
  path: u64,
- #[serde(
- serialize_with = "serialize_deps",
- deserialize_with = "deserialize_deps"
- )]
  deps: Vec<DepFingerprint>,
  local: Vec<LocalFingerprint>,
  #[serde(skip_serializing, skip_deserializing)]
@@ -174,32 +174,31 @@ pub struct Fingerprint {
  edition: Edition,
 }
 
-fn serialize_deps<S>(deps: &[DepFingerprint], ser: S) -> Result<S::Ok, S::Error>
-where
- S: ser::Serializer,
-{
- ser.collect_seq(deps.iter().map(|&(ref a, ref b, ref c)| (a, b, c.hash())))
+impl Serialize for DepFingerprint {
+ fn serialize<S>(&self, ser: S) -> Result<S::Ok, S::Error>
+ where
+ S: ser::Serializer,
+ {
+ (&self.pkg_id, &self.name, &self.fingerprint.hash()).serialize(ser)
+ }
 }
 
-fn deserialize_deps<'de, D>(d: D) -> Result<Vec<DepFingerprint>, D::Error>
-where
- D: de::Deserializer<'de>,
-{
- let decoded = <Vec<(String, String, u64)>>::deserialize(d)?;
- Ok(decoded
- .into_iter()
- .map(|(pkg_id, name, hash)| {
- (
- pkg_id,
- name,
- Arc::new(Fingerprint {
- local: vec![LocalFingerprint::Precalculated(String::new())],
- memoized_hash: Mutex::new(Some(hash)),
- ..Fingerprint::new()
- }),
- )
+impl<'de> Deserialize<'de> for DepFingerprint {
+ fn deserialize<D>(d: D) -> Result<DepFingerprint, D::Error>
+ where
+ D: de::Deserializer<'de>,
+ {
+ let (pkg_id, name, hash) = <(String, String, u64)>::deserialize(d)?;
+ Ok(DepFingerprint {
+ pkg_id,
+ name,
+ fingerprint: Arc::new(Fingerprint {
+ local: vec![LocalFingerprint::Precalculated(String::new())],
+ memoized_hash: Mutex::new(Some(hash)),
+ ..Fingerprint::new()
+ }),
  })
-  .collect())
+ }
 }
 
 #[derive(Serialize, Deserialize, Hash)]
@@ -352,8 +351,8 @@ impl Fingerprint {
  failure::bail!("number of dependencies has changed")
  }
  for (a, b) in self.deps.iter().zip(old.deps.iter()) {
- if a.1 != b.1 || a.2.hash() != b.2.hash() {
- failure::bail!("new ({}) != old ({})", a.0, b.0)
+ if a.name != b.name || a.fingerprint.hash() != b.fingerprint.hash() {
+ failure::bail!("new ({}) != old ({})", a.pkg_id, b.pkg_id)
  }
  }
  Ok(())
@@ -380,7 +379,12 @@ impl hash::Hash for Fingerprint {
  .hash(h);
 
  h.write_usize(deps.len());
- for &(ref pkg_id, ref name, ref fingerprint) in deps {
+ for DepFingerprint {
+ pkg_id,
+ name,
+ fingerprint,
+ } in deps
+ {
  pkg_id.hash(h);
  name.hash(h);
  // use memoized dep hashes to avoid exponential blowup
@@ -455,7 +459,11 @@ fn calculate<'a, 'cfg>(
  .map(|dep| {
  calculate(cx, dep).and_then(|fingerprint| {
  let name = cx.bcx.extern_crate_name(unit, dep)?;
- Ok((dep.pkg.package_id().to_string(), name, fingerprint))
+ Ok(DepFingerprint {
+ pkg_id: dep.pkg.package_id().to_string(),
+ name,
+ fingerprint,
+ })
  })
  })
  .collect::<CargoResult<Vec<_>>>()?;
@@ -470,7 +478,7 @@ fn calculate<'a, 'cfg>(
  LocalFingerprint::Precalculated(fingerprint)
  };
  let mut deps = deps;
- deps.sort_by(|&(ref a, _, _), &(ref b, _, _)| a.cmp(b));
+ deps.sort_by(|a, b| a.pkg_id.cmp(&b.pkg_id));
  let extra_flags = if unit.mode.is_doc() {
  bcx.rustdocflags_args(unit)?
  } else {