Auto merge of #5834 - Undin:metadata-edition, r=alexcrichton

Add edition info into metadata

Since edition feature was introduced, external tools have to support this new feature.
But cargo metadata doesn't provide info about package edition.
This commit adds edition field to `SerializedPackage` struct to add the corresponding field into metadata output.

src/cargo/core/manifest.rs

@@ -228,6 +228,7 @@ struct SerializedTarget<'a> {
     crate_types: Vec<&'a str>,
     name: &'a str,
     src_path: &'a PathBuf,
+    edition: &'a str,
 }
 
 impl ser::Serialize for Target {
@@ -237,6 +238,7 @@ impl ser::Serialize for Target {
             crate_types: self.rustc_crate_types(),
             name: &self.name,
             src_path: &self.src_path.path,
+            edition: &self.edition.to_string()
         }.serialize(s)
     }
 }

src/cargo/core/package.rs

@@ -47,6 +47,7 @@ struct SerializedPackage<'a> {
     keywords: &'a [String],
     readme: Option<&'a str>,
     repository: Option<&'a str>,
+    edition: &'a str,
 }
 
 impl ser::Serialize for Package {
@@ -84,6 +85,7 @@ impl ser::Serialize for Package {
             keywords,
             readme,
             repository,
+            edition: &self.manifest.edition().to_string(),
         }.serialize(s)
     }
 }

tests/testsuite/build.rs

@@ -3399,6 +3399,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["custom-build"],
             "crate_types":["bin"],
+            "edition": "2015",
             "name":"build-script-build",
             "src_path":"[..]build.rs"
         },
@@ -3420,6 +3421,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["lib"],
             "crate_types":["lib"],
+            "edition": "2015",
             "name":"bar",
             "src_path":"[..]lib.rs"
         },
@@ -3440,6 +3442,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["lib"],
             "crate_types":["lib"],
+            "edition": "2015",
             "name":"bar",
             "src_path":"[..]lib.rs"
         },
@@ -3462,6 +3465,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["bin"],
             "crate_types":["bin"],
+            "edition": "2015",
             "name":"foo",
             "src_path":"[..]main.rs"
         },
@@ -3474,6 +3478,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["bin"],
             "crate_types":["bin"],
+            "edition": "2015",
             "name":"foo",
             "src_path":"[..]main.rs"
         },
@@ -3504,6 +3509,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["custom-build"],
             "crate_types":["bin"],
+            "edition": "2015",
             "name":"build-script-build",
             "src_path":"[..]build.rs"
         },
@@ -3533,6 +3539,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["lib"],
             "crate_types":["lib"],
+            "edition": "2015",
             "name":"bar",
             "src_path":"[..]lib.rs"
         },
@@ -3555,6 +3562,7 @@ fn compiler_json_error_format() {
         "target":{
             "kind":["bin"],
             "crate_types":["bin"],
+            "edition": "2015",
             "name":"foo",
             "src_path":"[..]main.rs"
         },
@@ -3614,6 +3622,7 @@ fn message_format_json_forward_stderr() {
         "target":{
             "kind":["bin"],
             "crate_types":["bin"],
+            "edition": "2015",
             "name":"foo",
             "src_path":"[..]"
         },
@@ -3626,6 +3635,7 @@ fn message_format_json_forward_stderr() {
         "target":{
             "kind":["bin"],
             "crate_types":["bin"],
+            "edition": "2015",
             "name":"foo",
             "src_path":"[..]"
         },