Auto merge of #1419 - emilio:constified-enum-default, r=emilio

ir: Ensure everything agrees in which kind of variation an enum generates.

Fixes #1418.

7 files changed, 55 insertions, 26 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 830dde2f..6cf5fdc0 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -26,7 +26,7 @@ dependencies = [
 
 [[package]]
 name = "bindgen"
-version = "0.42.1"
+version = "0.42.2"
 dependencies = [
  "bitflags 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "cexpr 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/Cargo.toml b/Cargo.toml
index 094c1c62..2ea63fb6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,7 +14,7 @@ readme = "README.md"
 repository = "https://github.com/rust-lang-nursery/rust-bindgen"
 documentation = "https://docs.rs/bindgen"
 homepage = "https://rust-lang-nursery.github.io/rust-bindgen/"
-version = "0.42.1"
+version = "0.42.2"
 build = "build.rs"
 
 include = [
diff --git a/src/codegen/mod.rs b/src/codegen/mod.rs
index dc8271f9..f29a3bc0 100644
--- a/src/codegen/mod.rs
+++ b/src/codegen/mod.rs
@@ -2566,22 +2566,10 @@ impl CodeGenerator for Enum {
             }
         };
 
-        // ModuleConsts has higher precedence before Rust in order to avoid problems with
-        // overlapping match patterns
-        let variation = if self.is_constified_enum_module(ctx, item) {
-            EnumVariation::ModuleConsts
-        } else if self.is_bitfield(ctx, item) {
-            EnumVariation::Bitfield
-        } else if self.is_rustified_enum(ctx, item) {
-            EnumVariation::Rust
-        } else if self.is_constified_enum(ctx, item) {
-            EnumVariation::Consts
-        } else {
-            ctx.options().default_enum_style
-        };
-
         let mut attrs = vec![];
 
+        let variation = self.computed_enum_variation(ctx, item);
+
         // TODO(emilio): Delegate this to the builders?
         if variation.is_rust() {
             attrs.push(attributes::repr(repr_name));
diff --git a/src/ir/enum_ty.rs b/src/ir/enum_ty.rs
index ee705f16..6d1e7214 100644
--- a/src/ir/enum_ty.rs
+++ b/src/ir/enum_ty.rs
@@ -2,6 +2,7 @@
 
 use super::context::{BindgenContext, TypeId};
 use super::item::Item;
+use super::super::codegen::EnumVariation;
 use super::ty::TypeKind;
 use clang;
 use ir::annotations::Annotations;
@@ -150,25 +151,43 @@ impl Enum {
         path_matches || (enum_is_anon && a_variant_matches)
     }
 
-    /// Whether the enum should be a bitfield
-    pub fn is_bitfield(&self, ctx: &BindgenContext, item: &Item) -> bool {
+    /// Whether the enum was explicitly specified to be a bitfield.
+    fn is_bitfield(&self, ctx: &BindgenContext, item: &Item) -> bool {
         self.is_matching_enum(ctx, &ctx.options().bitfield_enums, item)
     }
 
-    /// Whether the enum should be an constified enum module
-    pub fn is_constified_enum_module(&self, ctx: &BindgenContext, item: &Item) -> bool {
+    /// Whether the enum was explicitly specified to be an constified enum
+    /// module.
+    fn is_constified_enum_module(&self, ctx: &BindgenContext, item: &Item) -> bool {
         self.is_matching_enum(ctx, &ctx.options().constified_enum_modules, item)
     }
 
-    /// Whether the enum should be an set of constants
-    pub fn is_constified_enum(&self, ctx: &BindgenContext, item: &Item) -> bool {
+    /// Whether the enum was explicitly specified to be an set of constants.
+    fn is_constified_enum(&self, ctx: &BindgenContext, item: &Item) -> bool {
         self.is_matching_enum(ctx, &ctx.options().constified_enums, item)
     }
 
-    /// Whether the enum should be a Rust enum
-    pub fn is_rustified_enum(&self, ctx: &BindgenContext, item: &Item) -> bool {
+    /// Whether the enum was explicitly specified to be a Rust enum.
+    fn is_rustified_enum(&self, ctx: &BindgenContext, item: &Item) -> bool {
         self.is_matching_enum(ctx, &ctx.options().rustified_enums, item)
     }
+
+    /// Returns the final representation of the enum.
+    pub fn computed_enum_variation(&self, ctx: &BindgenContext, item: &Item) -> EnumVariation {
+        // ModuleConsts has higher precedence before Rust in order to avoid
+        // problems with overlapping match patterns.
+        if self.is_constified_enum_module(ctx, item) {
+            EnumVariation::ModuleConsts
+        } else if self.is_bitfield(ctx, item) {
+            EnumVariation::Bitfield
+        } else if self.is_rustified_enum(ctx, item) {
+            EnumVariation::Rust
+        } else if self.is_constified_enum(ctx, item) {
+            EnumVariation::Consts
+        } else {
+            ctx.options().default_enum_style
+        }
+    }
 }
 
 /// A single enum variant, to be contained only in an enum.
diff --git a/src/ir/item.rs b/src/ir/item.rs
index 27e3d2f8..92372031 100644
--- a/src/ir/item.rs
+++ b/src/ir/item.rs
@@ -13,7 +13,7 @@ use super::function::{Function, FunctionKind};
 use super::item_kind::ItemKind;
 use super::layout::Opaque;
 use super::module::Module;
-use super::super::codegen::CONSTIFIED_ENUM_MODULE_REPR_NAME;
+use super::super::codegen::{CONSTIFIED_ENUM_MODULE_REPR_NAME, EnumVariation};
 use super::template::{AsTemplateParam, TemplateParameters};
 use super::traversal::{EdgeKind, Trace, Tracer};
 use super::ty::{Type, TypeKind};
@@ -928,7 +928,7 @@ impl Item {
 
         match *type_.kind() {
             TypeKind::Enum(ref enum_) => {
-                enum_.is_constified_enum_module(ctx, self)
+                enum_.computed_enum_variation(ctx, self) == EnumVariation::ModuleConsts
             }
             TypeKind::Alias(inner_id) => {
                 // TODO(emilio): Make this "hop through type aliases that aren't
diff --git a/tests/expectations/tests/default-enum-style-constified-module.rs b/tests/expectations/tests/default-enum-style-constified-module.rs
new file mode 100644
index 00000000..4b71efdd
--- /dev/null
+++ b/tests/expectations/tests/default-enum-style-constified-module.rs
@@ -0,0 +1,18 @@
+/* automatically generated by rust-bindgen */
+
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
+
+pub mod Foo {
+    pub type Type = u32;
+    pub const bar: Type = 0;
+    pub const baz: Type = 1;
+    pub const blap: Type = 2;
+}
+extern "C" {
+    pub fn func(x: Foo::Type);
+}
diff --git a/tests/headers/default-enum-style-constified-module.h b/tests/headers/default-enum-style-constified-module.h
new file mode 100644
index 00000000..a5ba6531
--- /dev/null
+++ b/tests/headers/default-enum-style-constified-module.h
@@ -0,0 +1,4 @@
+// bindgen-flags: --default-enum-style moduleconsts
+
+typedef enum { bar, baz, blap } Foo;
+void func(Foo x);