Use 'classifiers' instead of 'classifier'

Cargo.toml

@@ -13,7 +13,7 @@ edition = "2018"
 
 [package.metadata.maturin]
 requires-python = ">=3.5"
-classifier = [
+classifiers = [
     "Topic :: Software Development :: Build Tools",
     "Programming Language :: Rust",
     "Programming Language :: Python :: Implementation :: CPython",

Changelog.md

@@ -10,6 +10,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
  * Error when the `abi3` feature is selected but no minimum version
  * Support building universal2 wheels (x86 and aarch64 in a single file) by messense in [#403](https://github.com/PyO3/maturin/pull/403)
  * Recognize `PYO3_CROSS_LIB_DIR` for cross compiling with abi3 targeting windows. 
+ * `package.metadata.maturin.classifier` is renamed to `classifiers`
 
 ## 0.9.0 - 2020-01-10
 

Readme.md

@@ -124,13 +124,15 @@ Pip allows adding so called console scripts, which are shell commands that execu
 get_42 = "my_project:DummyClass.get_42"
 ```
 
-You can also specify [trove classifiers](https://pypi.org/classifiers/) in your Cargo.toml under `package.metadata.maturin.classifier`:
+You can also specify [trove classifiers](https://pypi.org/classifiers/) in your Cargo.toml under `package.metadata.maturin.classifiers`:
 
 ```toml
 [package.metadata.maturin]
-classifier = ["Programming Language :: Python"]
+classifiers = ["Programming Language :: Python"]
 ```
 
+Note that `package.metadata.maturin.classifier` is
+
 You can use other fields from the [python core metadata](https://packaging.python.org/specifications/core-metadata/) in the `[package.metadata.maturin]` section, specifically ` maintainer`, `maintainer-email` and `requires-python` (string fields), as well as `requires-external` and `provides-extra` (lists of strings) and `project-url` (dictionary string to string)
 
 ## pyproject.toml

src/cargo_toml.rs

@@ -70,13 +70,13 @@ impl CargoToml {
         }
     }
 
-    /// Returns the trove classifier
-    pub fn classifier(&self) -> Vec<String> {
+    /// Returns the trove classifiers
+    pub fn classifiers(&self) -> Vec<String> {
         match self.package.metadata {
             Some(CargoTomlMetadata {
                 maturin:
                     Some(RemainingCoreMetadata {
-                        classifier: Some(ref classifier),
+                        classifiers: Some(ref classifier),
                         ..
                     }),
             }) => classifier.clone(),
@@ -112,7 +112,9 @@ struct CargoTomlMetadata {
 pub struct RemainingCoreMetadata {
     pub name: Option<String>,
     pub scripts: Option<HashMap<String, String>>,
-    pub classifier: Option<Vec<String>>,
+    // For backward compatibility, we also allow classifier.
+    #[serde(alias = "classifier")]
+    pub classifiers: Option<Vec<String>>,
     pub maintainer: Option<String>,
     pub maintainer_email: Option<String>,
     pub requires_dist: Option<Vec<String>>,
@@ -148,7 +150,7 @@ mod test {
             ph = "maturin:print_hello"
 
             [package.metadata.maturin]
-            classifier = ["Programming Language :: Python"]
+            classifiers = ["Programming Language :: Python"]
             requires-dist = ["flask~=1.1.0", "toml==0.10.0"]
         "#
         );
@@ -158,15 +160,44 @@ mod test {
         let mut scripts = HashMap::new();
         scripts.insert("ph".to_string(), "maturin:print_hello".to_string());
 
-        let classifier = vec!["Programming Language :: Python".to_string()];
+        let classifiers = vec!["Programming Language :: Python".to_string()];
 
         let requires_dist = Some(vec!["flask~=1.1.0".to_string(), "toml==0.10.0".to_string()]);
 
         assert_eq!(cargo_toml.scripts(), scripts);
-        assert_eq!(cargo_toml.classifier(), classifier);
+        assert_eq!(cargo_toml.classifiers(), classifiers);
         assert_eq!(
             cargo_toml.remaining_core_metadata().requires_dist,
             requires_dist
         );
     }
+
+    #[test]
+    fn test_old_classifier_works() {
+        let cargo_toml = indoc!(
+            r#"
+            [package]
+            authors = ["konstin <konstin@mailbox.org>"]
+            name = "info-project"
+            version = "0.1.0"
+            description = "A test project"
+            homepage = "https://example.org"
+            keywords = ["ffi", "test"]
+
+            [lib]
+            crate-type = ["cdylib"]
+            name = "pyo3_pure"
+
+            [package.metadata.maturin]
+            # Not classifiers
+            classifier = ["Programming Language :: Python"]
+        "#
+        );
+
+        let cargo_toml: CargoToml = toml::from_str(&cargo_toml).unwrap();
+
+        let classifiers = vec!["Programming Language :: Python".to_string()];
+
+        assert_eq!(cargo_toml.classifiers(), classifiers);
+    }
 }

src/metadata.rs

@@ -44,7 +44,7 @@ pub struct Metadata21 {
     pub maintainer: Option<String>,
     pub maintainer_email: Option<String>,
     pub license: Option<String>,
-    pub classifier: Vec<String>,
+    pub classifiers: Vec<String>,
     pub requires_dist: Vec<String>,
     pub provides_dist: Vec<String>,
     pub obsoletes_dist: Vec<String>,
@@ -85,7 +85,7 @@ impl Metadata21 {
     ) -> Result<Metadata21> {
         let authors = cargo_toml.package.authors.join(", ");
 
-        let classifier = cargo_toml.classifier();
+        let classifiers = cargo_toml.classifiers();
 
         let author_email = if authors.contains('@') {
             Some(authors.clone())
@@ -137,7 +137,7 @@ impl Metadata21 {
             license: cargo_toml.package.license.clone(),
 
             // Values provided through `[project.metadata.maturin]`
-            classifier,
+            classifiers,
             maintainer: extra_metadata.maintainer,
             maintainer_email: extra_metadata.maintainer_email,
             requires_dist: extra_metadata.requires_dist.unwrap_or_default(),
@@ -175,7 +175,7 @@ impl Metadata21 {
         add_vec("Supported-Platform", &self.supported_platform);
         add_vec("Platform", &self.platform);
         add_vec("Supported-Platform", &self.supported_platform);
-        add_vec("Classifier", &self.classifier);
+        add_vec("Classifiers", &self.classifiers);
         add_vec("Requires-Dist", &self.requires_dist);
         add_vec("Provides-Dist", &self.provides_dist);
         add_vec("Obsoletes-Dist", &self.obsoletes_dist);
@@ -345,7 +345,7 @@ mod test {
             ph = "maturin:print_hello"
 
             [package.metadata.maturin]
-            classifier = ["Programming Language :: Python"]
+            classifiers = ["Programming Language :: Python"]
             requires-dist = ["flask~=1.1.0", "toml==0.10.0"]
             project-url = { "Bug Tracker" = "http://bitbucket.org/tarek/distribute/issues/" }
         "#
@@ -356,7 +356,7 @@ mod test {
             Metadata-Version: 2.1
             Name: info-project
             Version: 0.1.0
-            Classifier: Programming Language :: Python
+            Classifiers: Programming Language :: Python
             Requires-Dist: flask~=1.1.0
             Requires-Dist: toml==0.10.0
             Summary: A test project
@@ -404,7 +404,7 @@ mod test {
             ph = "maturin:print_hello"
 
             [package.metadata.maturin]
-            classifier = ["Programming Language :: Python"]
+            classifiers = ["Programming Language :: Python"]
             requires-dist = ["flask~=1.1.0", "toml==0.10.0"]
             description-content-type = "text/x-rst"
         "#
@@ -415,7 +415,7 @@ mod test {
             Metadata-Version: 2.1
             Name: info-project
             Version: 0.1.0
-            Classifier: Programming Language :: Python
+            Classifiers: Programming Language :: Python
             Requires-Dist: flask~=1.1.0
             Requires-Dist: toml==0.10.0
             Summary: A test project
@@ -453,7 +453,7 @@ mod test {
 
             [package.metadata.maturin]
             name = "info"
-            classifier = ["Programming Language :: Python"]
+            classifiers = ["Programming Language :: Python"]
             description-content-type = "text/x-rst"
         "#
         );
@@ -463,7 +463,7 @@ mod test {
             Metadata-Version: 2.1
             Name: info
             Version: 0.1.0
-            Classifier: Programming Language :: Python
+            Classifiers: Programming Language :: Python
             Summary: A test project
             Home-Page: https://example.org
             Author: konstin <konstin@mailbox.org>