From 7381ea019c47282985baab8752d27aca0a432023 Mon Sep 17 00:00:00 2001
From: bjorn3 <bjorn3@users.noreply.github.com>
Date: Fri, 4 Jun 2021 18:32:00 +0200
Subject: [PATCH] Remove emit_unit

It doesn't do anything for all encoders
---
 compiler/rustc_ast/src/ast.rs                   |  4 ++--
 compiler/rustc_metadata/src/rmeta/encoder.rs    |  5 -----
 compiler/rustc_middle/src/mir/predecessors.rs   |  4 ++--
 compiler/rustc_middle/src/mir/switch_sources.rs |  4 ++--
 compiler/rustc_middle/src/mir/traversal.rs      |  4 ++--
 compiler/rustc_query_impl/src/on_disk_cache.rs  |  5 -----
 compiler/rustc_serialize/src/opaque.rs          | 10 ----------
 compiler/rustc_serialize/src/serialize.rs       |  9 ++++-----
 8 files changed, 12 insertions(+), 33 deletions(-)

diff --git a/compiler/rustc_ast/src/ast.rs b/compiler/rustc_ast/src/ast.rs
index 09a3e53c7f0..b64f7b8ad1b 100644
--- a/compiler/rustc_ast/src/ast.rs
+++ b/compiler/rustc_ast/src/ast.rs
@@ -2473,8 +2473,8 @@ rustc_index::newtype_index! {
 }
 
 impl<S: Encoder> rustc_serialize::Encodable<S> for AttrId {
-    fn encode(&self, s: &mut S) -> Result<(), S::Error> {
-        s.emit_unit()
+    fn encode(&self, _s: &mut S) -> Result<(), S::Error> {
+        Ok(())
     }
 }
 
diff --git a/compiler/rustc_metadata/src/rmeta/encoder.rs b/compiler/rustc_metadata/src/rmeta/encoder.rs
index f67e1cab16d..1425c5467af 100644
--- a/compiler/rustc_metadata/src/rmeta/encoder.rs
+++ b/compiler/rustc_metadata/src/rmeta/encoder.rs
@@ -95,11 +95,6 @@ macro_rules! encoder_methods {
 impl<'a, 'tcx> Encoder for EncodeContext<'a, 'tcx> {
     type Error = <opaque::Encoder as Encoder>::Error;
 
-    #[inline]
-    fn emit_unit(&mut self) -> Result<(), Self::Error> {
-        Ok(())
-    }
-
     encoder_methods! {
         emit_usize(usize);
         emit_u128(u128);
diff --git a/compiler/rustc_middle/src/mir/predecessors.rs b/compiler/rustc_middle/src/mir/predecessors.rs
index ad09328585d..0b9ddaf64d4 100644
--- a/compiler/rustc_middle/src/mir/predecessors.rs
+++ b/compiler/rustc_middle/src/mir/predecessors.rs
@@ -56,8 +56,8 @@ impl PredecessorCache {
 
 impl<S: serialize::Encoder> serialize::Encodable<S> for PredecessorCache {
     #[inline]
-    fn encode(&self, s: &mut S) -> Result<(), S::Error> {
-        s.emit_unit()
+    fn encode(&self, _s: &mut S) -> Result<(), S::Error> {
+        Ok(())
     }
 }
 
diff --git a/compiler/rustc_middle/src/mir/switch_sources.rs b/compiler/rustc_middle/src/mir/switch_sources.rs
index adeeec70d1c..fbb26800e29 100644
--- a/compiler/rustc_middle/src/mir/switch_sources.rs
+++ b/compiler/rustc_middle/src/mir/switch_sources.rs
@@ -56,8 +56,8 @@ impl SwitchSourceCache {
 
 impl<S: serialize::Encoder> serialize::Encodable<S> for SwitchSourceCache {
     #[inline]
-    fn encode(&self, s: &mut S) -> Result<(), S::Error> {
-        s.emit_unit()
+    fn encode(&self, _s: &mut S) -> Result<(), S::Error> {
+        Ok(())
     }
 }
 
diff --git a/compiler/rustc_middle/src/mir/traversal.rs b/compiler/rustc_middle/src/mir/traversal.rs
index 1cbfed62156..5e8226d356f 100644
--- a/compiler/rustc_middle/src/mir/traversal.rs
+++ b/compiler/rustc_middle/src/mir/traversal.rs
@@ -367,8 +367,8 @@ impl PostorderCache {
 
 impl<S: serialize::Encoder> serialize::Encodable<S> for PostorderCache {
     #[inline]
-    fn encode(&self, s: &mut S) -> Result<(), S::Error> {
-        s.emit_unit()
+    fn encode(&self, _s: &mut S) -> Result<(), S::Error> {
+        Ok(())
     }
 }
 
diff --git a/compiler/rustc_query_impl/src/on_disk_cache.rs b/compiler/rustc_query_impl/src/on_disk_cache.rs
index 5a915933dc5..e93bf1a4752 100644
--- a/compiler/rustc_query_impl/src/on_disk_cache.rs
+++ b/compiler/rustc_query_impl/src/on_disk_cache.rs
@@ -993,11 +993,6 @@ where
 {
     type Error = E::Error;
 
-    #[inline]
-    fn emit_unit(&mut self) -> Result<(), Self::Error> {
-        Ok(())
-    }
-
     encoder_methods! {
         emit_usize(usize);
         emit_u128(u128);
diff --git a/compiler/rustc_serialize/src/opaque.rs b/compiler/rustc_serialize/src/opaque.rs
index 5e5cbacbcff..3bcb7cc3650 100644
--- a/compiler/rustc_serialize/src/opaque.rs
+++ b/compiler/rustc_serialize/src/opaque.rs
@@ -64,11 +64,6 @@ const STR_SENTINEL: u8 = 0xC1;
 impl serialize::Encoder for Encoder {
     type Error = !;
 
-    #[inline]
-    fn emit_unit(&mut self) -> EncodeResult {
-        Ok(())
-    }
-
     #[inline]
     fn emit_usize(&mut self, v: usize) -> EncodeResult {
         write_leb128!(self, v, usize, write_usize_leb128)
@@ -419,11 +414,6 @@ macro_rules! file_encoder_write_leb128 {
 impl serialize::Encoder for FileEncoder {
     type Error = io::Error;
 
-    #[inline]
-    fn emit_unit(&mut self) -> FileEncodeResult {
-        Ok(())
-    }
-
     #[inline]
     fn emit_usize(&mut self, v: usize) -> FileEncodeResult {
         file_encoder_write_leb128!(self, v, usize, write_usize_leb128)
diff --git a/compiler/rustc_serialize/src/serialize.rs b/compiler/rustc_serialize/src/serialize.rs
index 8c12d250f0f..817a0c9dcb1 100644
--- a/compiler/rustc_serialize/src/serialize.rs
+++ b/compiler/rustc_serialize/src/serialize.rs
@@ -15,7 +15,6 @@ pub trait Encoder {
     type Error;
 
     // Primitive types:
-    fn emit_unit(&mut self) -> Result<(), Self::Error>;
     fn emit_usize(&mut self, v: usize) -> Result<(), Self::Error>;
     fn emit_u128(&mut self, v: u128) -> Result<(), Self::Error>;
     fn emit_u64(&mut self, v: u64) -> Result<(), Self::Error>;
@@ -203,8 +202,8 @@ impl<D: Decoder> Decodable<D> for String {
 }
 
 impl<S: Encoder> Encodable<S> for () {
-    fn encode(&self, s: &mut S) -> Result<(), S::Error> {
-        s.emit_unit()
+    fn encode(&self, _s: &mut S) -> Result<(), S::Error> {
+        Ok(())
     }
 }
 
@@ -213,8 +212,8 @@ impl<D: Decoder> Decodable<D> for () {
 }
 
 impl<S: Encoder, T> Encodable<S> for PhantomData<T> {
-    fn encode(&self, s: &mut S) -> Result<(), S::Error> {
-        s.emit_unit()
+    fn encode(&self, _s: &mut S) -> Result<(), S::Error> {
+        Ok(())
     }
 }