Recover doc for inferred directory targets

First created in 6b94ed2238a3f378cfe4fda47922cef0908a942c and lost by
1271bb4de0c0e0a085be239c2418af9c673ffc87.

diff --git a/src/doc/src/reference/manifest.md b/src/doc/src/reference/manifest.md
index 71aede54306c9cdd86707063b2317007d3603db6..94680d07110399f622679c6c28045310e8671ac0 100644 (file)
--- a/src/doc/src/reference/manifest.md
+++ b/src/doc/src/reference/manifest.md
@@ -557,7 +557,8 @@ each file you want to build.
 
 Your project can optionally contain folders named `examples`, `tests`, and
 `benches`, which Cargo will treat as containing examples,
-integration tests, and benchmarks respectively.
+integration tests, and benchmarks respectively. Analogous to `bin` targets, they
+may be composed of single files or directories with a `main.rs` file.
 
 ```shell
 ▾ src/           # directory containing source files
@@ -569,10 +570,16 @@ integration tests, and benchmarks respectively.
     main.rs
 ▾ examples/      # (optional) examples
   *.rs
+▾ */             # (optional) directories containing multi-file examples
+  main.rs
 ▾ tests/         # (optional) integration tests
   *.rs
+▾ */             # (optional) directories containing multi-file tests
+  main.rs
 ▾ benches/       # (optional) benchmarks
   *.rs
+▾ */             # (optional) directories containing multi-file benchmarks
+  main.rs
 ```
 
 To structure your code after you've created the files and folders for your