Add support for enums (#33)

* Add support for enums * Emit C-style enums * Explain why enum is isize * Run cargo fmt
rust-diplomat · Jul 23, 2021 · 306367c · 306367c
1 parent 0513b67
commit 306367c
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Showing 17 changed files with 465 additions and 81 deletions.
diff --git a/core/src/ast/enums.rs b/core/src/ast/enums.rs
@@ -0,0 +1,85 @@
+use serde::{Deserialize, Serialize};
+
+use super::utils::get_doc_lines;
+use super::Method;
+
+/// A fieldless enum declaration in an FFI module.
+#[derive(Clone, Serialize, Deserialize, Debug)]
+pub struct Enum {
+    pub name: String,
+    pub doc_lines: String,
+    /// A list of variants of the enum. (name, discriminant, doc_lines)
+    pub variants: Vec<(String, isize, String)>,
+    pub methods: Vec<Method>,
+}
+
+impl From<&syn::ItemEnum> for Enum {
+    /// Extract an [`Enum`] metadata value from an AST node.
+    fn from(strct: &syn::ItemEnum) -> Enum {
+        let mut last_discriminant = -1;
+        Enum {
+            name: strct.ident.to_string(),
+            doc_lines: get_doc_lines(&strct.attrs),
+            variants: strct
+                .variants
+                .iter()
+                .map(|v| {
+                    let new_discriminant = v
+                        .discriminant
+                        .as_ref()
+                        .map(|d| {
+                            if let syn::Expr::Lit(syn::ExprLit {
+                                attrs: _,
+                                lit: syn::Lit::Int(lit_int),
+                            }) = &d.1
+                            {
+                                lit_int.base10_parse::<isize>().unwrap()
+                            } else {
+                                panic!("Expected a discriminant to be a constant integer");
+                            }
+                        })
+                        .unwrap_or_else(|| last_discriminant + 1);
+
+                    last_discriminant = new_discriminant;
+
+                    (
+                        v.ident.to_string(),
+                        new_discriminant,
+                        get_doc_lines(&v.attrs),
+                    )
+                })
+                .collect(),
+            methods: vec![],
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use insta::{self, Settings};
+
+    use quote::quote;
+    use syn;
+
+    use super::Enum;
+
+    #[test]
+    fn simple_enum() {
+        let mut settings = Settings::new();
+        settings.set_sort_maps(true);
+
+        settings.bind(|| {
+            insta::assert_yaml_snapshot!(Enum::from(
+                &syn::parse2(quote! {
+                    /// Some docs.
+                    enum MyLocalEnum {
+                        Abc,
+                        /// Some more docs.
+                        Def
+                    }
+                })
+                .unwrap()
+            ));
+        });
+    }
+}
diff --git a/core/src/ast/mod.rs b/core/src/ast/mod.rs
@@ -11,6 +11,9 @@ pub use modules::{File, Module};
 mod structs;
 pub use structs::{OpaqueStruct, Struct};
 
+mod enums;
+pub use enums::Enum;
+
 mod types;
 pub use types::{CustomType, ModSymbol, PrimitiveType, TypeName};
 

diff --git a/core/src/ast/modules.rs b/core/src/ast/modules.rs
@@ -4,7 +4,7 @@ use std::collections::HashMap;
 use quote::ToTokens;
 use syn::{ImplItem, Item, ItemMod, UseTree};
 
-use super::{CustomType, Method, ModSymbol, OpaqueStruct, Path, Struct, TypeName};
+use super::{CustomType, Enum, Method, ModSymbol, OpaqueStruct, Path, Struct, TypeName};
 
 #[derive(Clone, Serialize, Deserialize, Debug)]
 pub struct Module {
@@ -99,6 +99,14 @@ impl Module {
                         }
                     }
                 }
+
+                Item::Enum(enm) => {
+                    if analyze_types {
+                        custom_types_by_name
+                            .insert(enm.ident.to_string(), CustomType::Enum(Enum::from(enm)));
+                    }
+                }
+
                 Item::Impl(ipl) => {
                     if analyze_types {
                         assert!(ipl.trait_.is_none());
@@ -126,6 +134,9 @@ impl Module {
                             CustomType::Opaque(strct) => {
                                 strct.methods.append(&mut new_methods);
                             }
+                            CustomType::Enum(enm) => {
+                                enm.methods.append(&mut new_methods);
+                            }
                         }
                     }
                 }

diff --git a/core/src/ast/snapshots/diplomat_core__ast__enums__tests__simple_enum.snap b/core/src/ast/snapshots/diplomat_core__ast__enums__tests__simple_enum.snap
@@ -0,0 +1,16 @@
+---
+source: core/src/ast/enums.rs
+expression: "Enum::from(&syn::parse2(quote! {\n                            /// Some docs.\n                            enum MyLocalEnum\n                            {\n                                Abc, /// Some more docs.\n                                Def\n                            }\n                        }).unwrap())"
+
+---
+name: MyLocalEnum
+doc_lines: Some docs.
+variants:
+  - - Abc
+    - 0
+    - ""
+  - - Def
+    - 1
+    - Some more docs.
+methods: []
+
diff --git a/core/src/ast/types.rs b/core/src/ast/types.rs
@@ -7,16 +7,17 @@ use lazy_static::lazy_static;
 use std::collections::HashMap;
 use std::iter::FromIterator;
 
-use super::{Method, OpaqueStruct, Path, Struct};
+use super::{Enum, Method, OpaqueStruct, Path, Struct};
 
 /// A type declared inside a Diplomat-annotated module.
 #[derive(Clone, Serialize, Deserialize, Debug)]
 pub enum CustomType {
     /// A non-opaque struct whose fields will be visible across the FFI boundary.
     Struct(Struct),
-    // TODO(shadaj): Enum
     /// A struct annotated with [`diplomat::opaque`] whose fields are not visible.
     Opaque(OpaqueStruct),
+    /// A fieldless enum.
+    Enum(Enum),
 }
 
 impl CustomType {
@@ -25,6 +26,7 @@ impl CustomType {
         match self {
             CustomType::Struct(strct) => &strct.name,
             CustomType::Opaque(strct) => &strct.name,
+            CustomType::Enum(enm) => &enm.name,
         }
     }
 
@@ -33,6 +35,7 @@ impl CustomType {
         match self {
             CustomType::Struct(strct) => &strct.methods,
             CustomType::Opaque(strct) => &strct.methods,
+            CustomType::Enum(enm) => &enm.methods,
         }
     }
 
@@ -41,6 +44,7 @@ impl CustomType {
         match self {
             CustomType::Struct(strct) => &strct.doc_lines,
             CustomType::Opaque(strct) => &strct.doc_lines,
+            CustomType::Enum(enm) => &enm.doc_lines,
         }
     }
 
@@ -61,6 +65,7 @@ impl CustomType {
                 }
             }
             CustomType::Opaque(_) => {}
+            CustomType::Enum(_) => {}
         }
 
         for method in self.methods().iter() {

diff --git a/example/c/api.h b/example/c/api.h
@@ -13,11 +13,26 @@ typedef struct ICU4XFixedDecimal ICU4XFixedDecimal;
 
 typedef struct ICU4XFixedDecimalFormat ICU4XFixedDecimalFormat;
 
+enum ICU4XFixedDecimalGroupingStrategy {
+  ICU4XFixedDecimalGroupingStrategy_Auto = 0,
+  ICU4XFixedDecimalGroupingStrategy_Never = 1,
+  ICU4XFixedDecimalGroupingStrategy_Always = 2,
+  ICU4XFixedDecimalGroupingStrategy_Min2 = 3,
+};
+
+enum ICU4XFixedDecimalSignDisplay {
+  ICU4XFixedDecimalSignDisplay_Auto = 0,
+  ICU4XFixedDecimalSignDisplay_Never = 1,
+  ICU4XFixedDecimalSignDisplay_Always = 2,
+  ICU4XFixedDecimalSignDisplay_ExceptZero = 3,
+  ICU4XFixedDecimalSignDisplay_Negative = 4,
+};
+
 typedef struct ICU4XLocale ICU4XLocale;
 
 typedef struct ICU4XFixedDecimalFormatOptions {
-    uint8_t grouping_strategy;
-    uint8_t sign_display;
+    ssize_t grouping_strategy;
+    ssize_t sign_display;
 } ICU4XFixedDecimalFormatOptions;
 
 typedef struct ICU4XFixedDecimalFormatResult {
@@ -45,6 +60,8 @@ void ICU4XFixedDecimalFormat_destroy(ICU4XFixedDecimalFormat* self);
 ICU4XFixedDecimalFormatOptions ICU4XFixedDecimalFormatOptions_default();
 void ICU4XFixedDecimalFormatOptions_destroy(ICU4XFixedDecimalFormatOptions* self);
 void ICU4XFixedDecimalFormatResult_destroy(ICU4XFixedDecimalFormatResult* self);
+void ICU4XFixedDecimalGroupingStrategy_destroy(ssize_t* self);
+void ICU4XFixedDecimalSignDisplay_destroy(ssize_t* self);
 
 ICU4XLocale* ICU4XLocale_new(const char* name_data, size_t name_len);
 void ICU4XLocale_destroy(ICU4XLocale* self);

diff --git a/example/cpp/api.h b/example/cpp/api.h
@@ -13,11 +13,26 @@ typedef struct ICU4XFixedDecimal ICU4XFixedDecimal;
 
 typedef struct ICU4XFixedDecimalFormat ICU4XFixedDecimalFormat;
 
+enum ICU4XFixedDecimalGroupingStrategy {
+  ICU4XFixedDecimalGroupingStrategy_Auto = 0,
+  ICU4XFixedDecimalGroupingStrategy_Never = 1,
+  ICU4XFixedDecimalGroupingStrategy_Always = 2,
+  ICU4XFixedDecimalGroupingStrategy_Min2 = 3,
+};
+
+enum ICU4XFixedDecimalSignDisplay {
+  ICU4XFixedDecimalSignDisplay_Auto = 0,
+  ICU4XFixedDecimalSignDisplay_Never = 1,
+  ICU4XFixedDecimalSignDisplay_Always = 2,
+  ICU4XFixedDecimalSignDisplay_ExceptZero = 3,
+  ICU4XFixedDecimalSignDisplay_Negative = 4,
+};
+
 typedef struct ICU4XLocale ICU4XLocale;
 
 typedef struct ICU4XFixedDecimalFormatOptions {
-    uint8_t grouping_strategy;
-    uint8_t sign_display;
+    ssize_t grouping_strategy;
+    ssize_t sign_display;
 } ICU4XFixedDecimalFormatOptions;
 
 typedef struct ICU4XFixedDecimalFormatResult {
@@ -45,6 +60,8 @@ void ICU4XFixedDecimalFormat_destroy(ICU4XFixedDecimalFormat* self);
 ICU4XFixedDecimalFormatOptions ICU4XFixedDecimalFormatOptions_default();
 void ICU4XFixedDecimalFormatOptions_destroy(ICU4XFixedDecimalFormatOptions* self);
 void ICU4XFixedDecimalFormatResult_destroy(ICU4XFixedDecimalFormatResult* self);
+void ICU4XFixedDecimalGroupingStrategy_destroy(ssize_t* self);
+void ICU4XFixedDecimalSignDisplay_destroy(ssize_t* self);
 
 ICU4XLocale* ICU4XLocale_new(const char* name_data, size_t name_len);
 void ICU4XLocale_destroy(ICU4XLocale* self);

diff --git a/example/cpp/api.hpp b/example/cpp/api.hpp
@@ -17,6 +17,21 @@ struct ICU4XFixedDecimalFormatOptions;
 
 struct ICU4XFixedDecimalFormatResult;
 
+enum struct ICU4XFixedDecimalGroupingStrategy : ssize_t {
+  Auto = 0,
+  Never = 1,
+  Always = 2,
+  Min2 = 3,
+};
+
+enum struct ICU4XFixedDecimalSignDisplay : ssize_t {
+  Auto = 0,
+  Never = 1,
+  Always = 2,
+  ExceptZero = 3,
+  Negative = 4,
+};
+
 class ICU4XLocale;
 
 struct ICU4XDataProviderDeleter {
@@ -86,8 +101,8 @@ struct ICU4XFixedDecimalFormatOptionsDeleter {
 };
 struct ICU4XFixedDecimalFormatOptions {
  public:
-  uint8_t grouping_strategy;
-  uint8_t sign_display;
+  ICU4XFixedDecimalGroupingStrategy grouping_strategy;
+  ICU4XFixedDecimalSignDisplay sign_display;
   static ICU4XFixedDecimalFormatOptions default_();
 };
 
@@ -124,7 +139,7 @@ std::string ICU4XFixedDecimal::to_string() {
 
 ICU4XFixedDecimalFormatResult ICU4XFixedDecimalFormat::try_new(const ICU4XLocale& locale, const ICU4XDataProvider& provider, ICU4XFixedDecimalFormatOptions options) {
   ICU4XFixedDecimalFormatOptions diplomat_wrapped_struct_options = options;
-  capi::ICU4XFixedDecimalFormatResult diplomat_raw_struct_out_value = capi::ICU4XFixedDecimalFormat_try_new(locale.AsFFI(), provider.AsFFI(), capi::ICU4XFixedDecimalFormatOptions{ .grouping_strategy = diplomat_wrapped_struct_options.grouping_strategy, .sign_display = diplomat_wrapped_struct_options.sign_display });
+  capi::ICU4XFixedDecimalFormatResult diplomat_raw_struct_out_value = capi::ICU4XFixedDecimalFormat_try_new(locale.AsFFI(), provider.AsFFI(), capi::ICU4XFixedDecimalFormatOptions{ .grouping_strategy = static_cast<ssize_t>(diplomat_wrapped_struct_options.grouping_strategy), .sign_display = static_cast<ssize_t>(diplomat_wrapped_struct_options.sign_display) });
   auto diplomat_optional_raw_out_value_fdf = diplomat_raw_struct_out_value.fdf;
   std::optional<ICU4XFixedDecimalFormat> diplomat_optional_out_value_fdf;
   if (diplomat_optional_raw_out_value_fdf != nullptr) {
@@ -143,10 +158,12 @@ std::string ICU4XFixedDecimalFormat::format_write(const ICU4XFixedDecimal& value
 
 ICU4XFixedDecimalFormatOptions ICU4XFixedDecimalFormatOptions::default_() {
   capi::ICU4XFixedDecimalFormatOptions diplomat_raw_struct_out_value = capi::ICU4XFixedDecimalFormatOptions_default();
-  return ICU4XFixedDecimalFormatOptions{ .grouping_strategy = std::move(diplomat_raw_struct_out_value.grouping_strategy), .sign_display = std::move(diplomat_raw_struct_out_value.sign_display) };
+  return ICU4XFixedDecimalFormatOptions{ .grouping_strategy = std::move(ICU4XFixedDecimalGroupingStrategy{ diplomat_raw_struct_out_value.grouping_strategy }), .sign_display = std::move(ICU4XFixedDecimalSignDisplay{ diplomat_raw_struct_out_value.sign_display }) };
 }
 
 
+
+
 ICU4XLocale ICU4XLocale::new_(const std::string name) {
   return ICU4XLocale(capi::ICU4XLocale_new(name.data(), name.length()));
 }