Lift the requirement that cargo is built with make

Cargo should be able to build with cargo so others can depend on the cargo
library. This means that the one requirement of the CFG_VERSION env var will not
be available. This alters `version()` to prioritize CFG_VERSION but fall back to
the cargo-specified variables.

diff --git a/src/cargo/lib.rs b/src/cargo/lib.rs
index f80f38d2e83e0444ebc6cf151e1c71603cdc63e0..89baab02194bdba5ea8144083985b9120a8d83d4 100644 (file)
--- a/src/cargo/lib.rs
+++ b/src/cargo/lib.rs
@@ -200,7 +200,14 @@ fn handle_cause(err: &CargoError, shell: &mut MultiShell) {
 }
 
 pub fn version() -> String {
-    format!("cargo {}", env!("CFG_VERSION"))
+    format!("cargo {}", match option_env!("CFG_VERSION") {
+        Some(s) => s.to_string(),
+        None => format!("{}.{}.{}{}",
+                        env!("CARGO_PKG_VERSION_MAJOR"),
+                        env!("CARGO_PKG_VERSION_MINOR"),
+                        env!("CARGO_PKG_VERSION_PATCH"),
+                        option_env!("CARGO_PKG_VERSION_PRE").unwrap_or(""))
+    })
 }
 
 fn flags_from_args<T: FlagParser>(args: &[String],