Inspect CFG_RELEASE_CHANNEL env var at compile time

topecongiro · topecongiro · commit ef4b3d9bfa94 · 2017-12-04T11:34:27.000+09:00
diff --git a/src/config.rs b/src/config.rs
@@ -24,9 +24,9 @@ use Summary;
 
 macro_rules! is_nightly_channel {
     () => {
-    env::var("CFG_RELEASE_CHANNEL")
-        .map(|c| c == "nightly")
-        .unwrap_or(false)
+        option_env!("CFG_RELEASE_CHANNEL")
+            .map(|c| c == "nightly")
+            .unwrap_or(false)
     }
 }
 

Original file line number	Diff line number	Diff line change
`@@ -24,9 +24,9 @@ use Summary;`
`24`	`24`
`25`	`25`	`macro_rules! is_nightly_channel {`
`26`	`26`	`() => {`
`27`		`- env::var("CFG_RELEASE_CHANNEL")`
`28`		`- .map(\|c\| c == "nightly")`
`29`		`- .unwrap_or(false)`
	`27`	`+ option_env!("CFG_RELEASE_CHANNEL")`
	`28`	`+ .map(\|c\| c == "nightly")`
	`29`	`+ .unwrap_or(false)`
`30`	`30`	`}`
`31`	`31`	`}`
`32`	`32`