add rfc#3662 tests, plus multi letter test crates

* Adds tests for the behavior in rfc#3662
* Renames single variable test crate names to multi letter crate names in
  tests/rustdoc/cross-crate-info (i.e. s.rs -> sierra.rs)

Author: EtomicBomb

tests/rustdoc/cross-crate-info/cargo-transitive-no-index/auxiliary/quebec.rs

@@ -0,0 +1,2 @@
+//@ unique-doc-out-dir
+pub struct Quebec;

tests/rustdoc/cross-crate-info/cargo-transitive-no-index/auxiliary/t.rs

@@ -0,0 +1,5 @@
+//@ aux-build:quebec.rs
+//@ build-aux-docs
+//@ unique-doc-out-dir
+extern crate quebec;
+pub trait Tango {}

tests/rustdoc/cross-crate-info/cargo-transitive-no-index/auxiliary/tango.rs

@@ -0,0 +1,18 @@
+//@ aux-build:tango.rs
+//@ build-aux-docs
+//@ !has index.html
+//@ !has quebec/struct.Quebec.html
+//@ !has tango/trait.Tango.html
+//@ has sierra/struct.Sierra.html
+//@ hasraw sierra/struct.Sierra.html 'Tango'
+//@ hasraw trait.impl/tango/trait.Tango.js 'struct.Sierra.html'
+//@ !hasraw search-index.js 'Tango'
+//@ !hasraw search-index.js 'Quebec'
+//@ hasraw search-index.js 'Sierra'
+
+// We use the regular and transitive dependencies.Both should appear in
+// the item docs for the final crate. The index page is not generated,
+// however.
+extern crate tango;
+pub struct Sierra;
+impl tango::Tango for Sierra {}

tests/rustdoc/cross-crate-info/cargo-transitive-no-index/s.rs

@@ -0,0 +1,5 @@
+//@ doc-flags:--merge=shared
+//@ doc-flags:--enable-index-page
+//@ doc-flags:-Zunstable-options
+
+pub struct Quebec;

tests/rustdoc/cross-crate-info/cargo-transitive-no-index/sierra.rs

@@ -0,0 +1,8 @@
+//@ aux-build:quebec.rs
+//@ build-aux-docs
+//@ doc-flags:--merge=shared
+//@ doc-flags:--enable-index-page
+//@ doc-flags:-Zunstable-options
+
+extern crate quebec;
+pub trait Tango {}

tests/rustdoc/cross-crate-info/cargo-transitive-read-write/auxiliary/quebec.rs

@@ -0,0 +1,25 @@
+//@ aux-build:tango.rs
+//@ build-aux-docs
+//@ doc-flags:--merge=shared
+//@ doc-flags:--enable-index-page
+//@ doc-flags:-Zunstable-options
+
+//@ has index.html
+//@ has index.html '//h1' 'List of all crates'
+//@ has index.html '//ul[@class="all-items"]//a[@href="quebec/index.html"]' 'quebec'
+//@ has index.html '//ul[@class="all-items"]//a[@href="sierra/index.html"]' 'sierra'
+//@ has index.html '//ul[@class="all-items"]//a[@href="tango/index.html"]' 'tango'
+//@ has quebec/struct.Quebec.html
+//@ has sierra/struct.Sierra.html
+//@ has tango/trait.Tango.html
+//@ hasraw sierra/struct.Sierra.html 'Tango'
+//@ hasraw trait.impl/tango/trait.Tango.js 'struct.Sierra.html'
+//@ hasraw search-index.js 'Tango'
+//@ hasraw search-index.js 'Sierra'
+//@ hasraw search-index.js 'Quebec'
+
+// similar to cargo-workflow-transitive, but we use --merge=read-write,
+// which is the default.
+extern crate tango;
+pub struct Sierra;
+impl tango::Tango for Sierra {}

tests/rustdoc/cross-crate-info/cargo-transitive-read-write/auxiliary/tango.rs

@@ -1,4 +1,4 @@
-//@ build-aux-docs
+//@ unique-doc-out-dir
 //@ doc-flags:--enable-index-page
 //@ doc-flags:-Zunstable-options
 

tests/rustdoc/cross-crate-info/cargo-transitive-read-write/sierra.rs

@@ -1,7 +1,8 @@
-//@ aux-build:q.rs
+//@ aux-build:quebec.rs
 //@ build-aux-docs
+//@ unique-doc-out-dir
 //@ doc-flags:--enable-index-page
 //@ doc-flags:-Zunstable-options
 
-extern crate q;
+extern crate quebec;
 pub trait Tango {}