cargo install: suggest --git when package name is url

src/bin/cargo/commands/install.rs

@@ -121,6 +121,14 @@ pub fn exec(config: &mut Config, args: &ArgMatches) -> CliResult {
             )
             .into());
         }
+
+        if let Ok(url) = crate_name.into_url() {
+            return Err(anyhow!(
+                "invalid package name: `{url}`
+    Use `cargo install --git {url}` if you meant to install from a git repository."
+            )
+            .into());
+        }
     }
 
     let mut from_cwd = false;

tests/testsuite/install.rs

@@ -71,6 +71,18 @@ fn toolchain() {
         .run();
 }
 
+#[cargo_test]
+fn url() {
+    pkg("foo", "0.0.1");
+    cargo_process("install https://github.com/bar/foo")
+        .with_status(101)
+        .with_stderr(
+            "\
+[ERROR] invalid package name: `https://github.com/bar/foo`
+    Use `cargo install --git https://github.com/bar/foo` if you meant to install from a git repository.")
+        .run();
+}
+
 #[cargo_test]
 fn simple_with_message_format() {
     pkg("foo", "0.0.1");