Rollup merge of #59825 - jsgf:from-ref-string, r=sfackler

Centril · web-flow · commit f08c5bbc850a · 2019-05-16T10:43:24.000+02:00
string: implement From<&String> for String Allow Strings to be created from borrowed Strings. This is mostly to make things like passing `&String` to an `impl Into<String>` parameter frictionless. Fixes #59827.
diff --git a/src/liballoc/string.rs b/src/liballoc/string.rs
@@ -2189,6 +2189,14 @@ impl From<&str> for String {
     }
 }
 
+#[stable(feature = "from_ref_string", since = "1.35.0")]
+impl From<&String> for String {
+    #[inline]
+    fn from(s: &String) -> String {
+        s.clone()
+    }
+}
+
 // note: test pulls in libstd, which causes errors here
 #[cfg(not(test))]
 #[stable(feature = "string_from_box", since = "1.18.0")]

Original file line number	Diff line number	Diff line change
`@@ -2189,6 +2189,14 @@ impl From<&str> for String {`
`2189`	`2189`	`}`
`2190`	`2190`	`}`
`2191`	`2191`
	`2192`	`+#[stable(feature = "from_ref_string", since = "1.35.0")]`
	`2193`	`+impl From<&String> for String {`
	`2194`	`+ #[inline]`
	`2195`	`+ fn from(s: &String) -> String {`
	`2196`	`+ s.clone()`
	`2197`	`+ }`
	`2198`	`+}`
	`2199`	`+`
`2192`	`2200`	`// note: test pulls in libstd, which causes errors here`
`2193`	`2201`	`#[cfg(not(test))]`
`2194`	`2202`	`#[stable(feature = "string_from_box", since = "1.18.0")]`