rustdoc: generate implementors for all auto traits

Previously we would only generate a list of synthetic implementations
for two well known traits – Send and Sync. With this patch all the auto
traits known to rustc are considered. This includes such traits like
Unpin and user’s own traits.

Sadly the implementation still iterates through the list of crate items
and checks them against the traits, which for non-std crates containing
their own auto-traits will still not include types defined in std/core.

It is an improvement nontheless.

5 files changed, 15 insertions, 3 deletions

diff --git a/src/test/rustdoc/empty-section.rs b/src/test/rustdoc/empty-section.rs
index 619f2d688a1..d95f3a80365 100644
--- a/src/test/rustdoc/empty-section.rs
+++ b/src/test/rustdoc/empty-section.rs
@@ -8,3 +8,6 @@ pub struct Foo;
 // @!has - 'Auto Trait Implementations'
 impl !Send for Foo {}
 impl !Sync for Foo {}
+impl !std::marker::Unpin for Foo {}
+impl !std::panic::RefUnwindSafe for Foo {}
+impl !std::panic::UnwindSafe for Foo {}
diff --git a/src/test/rustdoc/issue-50159.rs b/src/test/rustdoc/issue-50159.rs
index d175c82ec87..74502be622a 100644
--- a/src/test/rustdoc/issue-50159.rs
+++ b/src/test/rustdoc/issue-50159.rs
@@ -14,7 +14,7 @@ impl<B, C> Signal2 for B where B: Signal<Item = C> {
 // @has - '//code' 'impl<B> Send for Switch<B> where <B as Signal>::Item: Send'
 // @has - '//code' 'impl<B> Sync for Switch<B> where <B as Signal>::Item: Sync'
 // @count - '//*[@id="implementations-list"]/*[@class="impl"]' 0
-// @count - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]' 2
+// @count - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]' 5
 pub struct Switch<B: Signal> {
     pub inner: <B as Signal2>::Item2,
 }
diff --git a/src/test/rustdoc/synthetic_auto/basic.rs b/src/test/rustdoc/synthetic_auto/basic.rs
index d5f1269d08a..38de5316b6c 100644
--- a/src/test/rustdoc/synthetic_auto/basic.rs
+++ b/src/test/rustdoc/synthetic_auto/basic.rs
@@ -2,7 +2,7 @@
 // @has - '//code' 'impl<T> Send for Foo<T> where T: Send'
 // @has - '//code' 'impl<T> Sync for Foo<T> where T: Sync'
 // @count - '//*[@id="implementations-list"]/*[@class="impl"]' 0
-// @count - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]' 2
+// @count - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]' 5
 pub struct Foo<T> {
     field: T,
 }
diff --git a/src/test/rustdoc/synthetic_auto/crate-local.rs b/src/test/rustdoc/synthetic_auto/crate-local.rs
new file mode 100644
index 00000000000..341dd572f81
--- /dev/null
+++ b/src/test/rustdoc/synthetic_auto/crate-local.rs
@@ -0,0 +1,9 @@
+#![feature(optin_builtin_traits)]
+
+pub auto trait Banana {}
+
+// @has crate_local/struct.Peach.html
+// @has - '//code' 'impl Banana for Peach'
+// @has - '//code' 'impl Send for Peach'
+// @has - '//code' 'impl Sync for Peach'
+pub struct Peach;
diff --git a/src/test/rustdoc/synthetic_auto/manual.rs b/src/test/rustdoc/synthetic_auto/manual.rs
index 413ba187f45..458403462d6 100644
--- a/src/test/rustdoc/synthetic_auto/manual.rs
+++ b/src/test/rustdoc/synthetic_auto/manual.rs
@@ -6,7 +6,7 @@
 // 'impl<T> Send for Foo<T>'
 //
 // @count - '//*[@id="implementations-list"]/*[@class="impl"]' 1
-// @count - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]' 1
+// @count - '//*[@id="synthetic-implementations-list"]/*[@class="impl"]' 4
 pub struct Foo<T> {
     field: T,
 }