Support kebab-case names in parse sepc

README.md

@@ -47,6 +47,23 @@ $ RUST_LOG=info ./main
 [2018-11-03T06:09:06Z INFO  default] starting up
 ```
 
+To set the log level on a per module basis, module names can be declared as `path::to::module=level` in **`RUST_LOG`**.
+
+```console
+$ RUST_LOG=main=info ./main
+[2017-11-09T02:12:24Z ERROR main] this is printed by default
+[2017-11-09T02:12:24Z INFO main] the answer was: 12
+```
+
+When dealing with crate name with hyphens, either the original form (e.g., `my-app`) or the canonical form (e.g., `my_app`) works.
+
+```console
+$ RUST_LOG=my-app ./my-app   # `RUST_LOG=my_app ./my-app` also works
+[2017-11-09T02:12:24Z DEBUG my_app] this is a debug message
+[2017-11-09T02:12:24Z ERROR my_app] this is printed by default
+[2017-11-09T02:12:24Z INFO my_app] the answer was: 12
+```
+
 The letter case is not significant for the logging level names; e.g., `debug`,
 `DEBUG`, and `dEbuG` all represent the same logging level. Therefore, the
 previous example could also have been written this way, specifying the log

src/filter/mod.rs

@@ -336,7 +336,7 @@ fn parse_spec(spec: &str) -> (Vec<Directive>, Option<inner::Filter>) {
                     }
                 };
             dirs.push(Directive {
-                name: name.map(|s| s.to_string()),
+                name: name.map(|s| s.replace("-", "_")),
                 level: log_level,
             });
         }
@@ -860,4 +860,16 @@ mod tests {
         assert_eq!(dirs[0].level, LevelFilter::max());
         assert!(filter.is_some() && filter.unwrap().to_string() == "a*c");
     }
+
+    #[test]
+    fn parse_spec_name_canonicalization() {
+        // accept binary names in both styles (`snake_case` and `kebab-case`)
+        let (dirs, _) = parse_spec("snake_case_crate=info,kebab-case-crate=debug");
+        assert_eq!(dirs.len(), 2);
+        assert_eq!(dirs[0].name, Some("snake_case_crate".to_string()));
+        assert_eq!(dirs[0].level, LevelFilter::Info);
+
+        assert_eq!(dirs[1].name, Some("kebab_case_crate".to_string()));
+        assert_eq!(dirs[1].level, LevelFilter::Debug);
+    }
 }

src/lib.rs

@@ -71,11 +71,12 @@
 //! [2017-11-09T02:12:24Z INFO main] the answer was: 12
 //! ```
 //!
-//! If the binary name contains hyphens, you will need to replace
-//! them with underscores:
+//! Some package names may contain hyphens, this logger does the conversion for
+//! you so you don't have to. You are free to use the original form (`my-app`)
+//! or the canonical form (`my_app`).
 //!
 //! ```{.bash}
-//! $ RUST_LOG=my_app ./my-app
+//! $ RUST_LOG=my-app ./my-app
 //! [2017-11-09T02:12:24Z DEBUG my_app] this is a debug message
 //! [2017-11-09T02:12:24Z ERROR my_app] this is printed by default
 //! [2017-11-09T02:12:24Z INFO my_app] the answer was: 12