Auto merge of rust-lang#13640 - ehuss:fix-doc-dash-collision, r=epage

Fix doc collision for lib/bin with a dash in the inferred name.

This fixes an issue where `cargo doc` would report a collision if the project has a `-` in the name, and both a lib and bin. As a consequence of the change in rust-lang#12783, the target name for the library no longer has a `-`. The code that checks for the lib/bin doc collision was only checking if the target names were equal, which is no longer the case after rust-lang#12783. The solution here is to use the `crate_name` and not the target name, which has the appropriate `_` translation done. This is the more correct method to use, even before rust-lang#12783, because rustdoc uses crate names, not target names (and thus even documenting bins have their filenames converted to underscores).

Fixes rust-lang#13628

src/cargo/ops/cargo_compile/unit_generator.rs

@@ -198,7 +198,9 @@ impl<'a> UnitGenerator<'a, '_> {
                     .filter(|t| {
                         t.documented()
                             && (!t.is_bin()
-                                || !targets.iter().any(|l| l.is_lib() && l.name() == t.name()))
+                                || !targets
+                                    .iter()
+                                    .any(|l| l.is_lib() && l.crate_name() == t.crate_name()))
                     })
                     .collect()
             }

tests/testsuite/doc.rs

@@ -478,6 +478,28 @@ fn doc_lib_bin_same_name_documents_lib_when_requested() {
     assert!(!doc_html.contains("Binary"));
 }
 
+#[cargo_test]
+fn doc_lib_bin_same_name_with_dash() {
+    // Checks `doc` behavior when there is a dash in the package name, and
+    // there is a lib and bin, and the lib name is inferred.
+    let p = project()
+        .file("Cargo.toml", &basic_manifest("foo-bar", "1.0.0"))
+        .file("src/lib.rs", "")
+        .file("src/main.rs", "fn main() {}")
+        .build();
+    p.cargo("doc")
+        .with_stderr(
+            "\
+[DOCUMENTING] foo-bar v1.0.0 ([ROOT]/foo)
+[FINISHED] [..]
+[GENERATED] [ROOT]/foo/target/doc/foo_bar/index.html
+",
+        )
+        .run();
+    assert!(p.build_dir().join("doc/foo_bar/index.html").exists());
+    assert!(!p.build_dir().join("doc/foo_bar/fn.main.html").exists());
+}
+
 #[cargo_test]
 fn doc_lib_bin_same_name_documents_named_bin_when_requested() {
     let p = project()