Auto merge of #1003 - pepyakin:derive-ord-when-possible, r=fitzgen

Derive ord when possible

Fixes #884

r? @fitzgen

Author: bors-servo

src/codegen/mod.rs

@@ -12,8 +12,8 @@ use ir::comp::{Base, Bitfield, BitfieldUnit, CompInfo, CompKind, Field,
                FieldData, FieldMethods, Method, MethodKind};
 use ir::context::{BindgenContext, ItemId};
 use ir::derive::{CanDeriveCopy, CanDeriveDebug, CanDeriveDefault,
-                 CanDeriveHash, CanDerivePartialOrd, CanDerivePartialEq,
-                 CanDeriveEq};
+                 CanDeriveHash, CanDerivePartialOrd, CanDeriveOrd,
+                 CanDerivePartialEq, CanDeriveEq};
 use ir::dot;
 use ir::enum_ty::{Enum, EnumVariant, EnumVariantValue};
 use ir::function::{Abi, Function, FunctionSig};
@@ -1494,6 +1494,10 @@ impl CodeGenerator for CompInfo {
             derives.push("PartialOrd");
         }
 
+        if item.can_derive_ord(ctx) {
+            derives.push("Ord");
+        }
+
         if item.can_derive_partialeq(ctx) {
             derives.push("PartialEq");
         }

src/ir/context.rs

@@ -6,8 +6,8 @@ use super::analysis::{CannotDeriveCopy, CannotDeriveDebug,
                       HasVtableAnalysis, HasDestructorAnalysis, UsedTemplateParameters,
                       HasFloat, analyze};
 use super::derive::{CanDeriveCopy, CanDeriveDebug, CanDeriveDefault,
-                    CanDeriveHash, CanDerivePartialOrd, CanDerivePartialEq,
-                    CanDeriveEq};
+                    CanDeriveHash, CanDerivePartialOrd, CanDeriveOrd,
+                    CanDerivePartialEq, CanDeriveEq};
 use super::int::IntKind;
 use super::item::{HasTypeParamInArray, IsOpaque, Item, ItemAncestors,
                   ItemCanonicalPath, ItemSet};
@@ -91,6 +91,14 @@ impl CanDeriveEq for ItemId {
     }
 }
 
+impl CanDeriveOrd for ItemId {
+    fn can_derive_ord(&self, ctx: &BindgenContext) -> bool {
+        ctx.options().derive_ord &&
+            ctx.lookup_item_id_can_derive_partialeq_or_partialord(*self) &&
+            !ctx.lookup_item_id_has_float(&self)
+    }
+}
+
 /// A key used to index a resolved type, so we only process it once.
 ///
 /// This is almost always a USR string (an unique identifier generated by
@@ -2191,7 +2199,7 @@ impl BindgenContext {
     fn compute_has_float(&mut self) {
         let _t = self.timer("compute_has_float");
         assert!(self.has_float.is_none());
-        if self.options.derive_eq {
+        if self.options.derive_eq || self.options.derive_ord {
             self.has_float = Some(analyze::<HasFloat>(self));
         }
     }

src/ir/derive.rs

@@ -97,7 +97,7 @@ pub trait CanDerivePartialEq {
 ///
 /// This should ideally be a no-op that just returns `true`, but instead needs
 /// to be a recursive method that checks whether all the proper members can
-/// derive default or not, because of the limit rust has on 32 items as max in the
+/// derive partial ord or not, because of the limit rust has on 32 items as max in the
 /// array.
 pub trait CanDerivePartialOrd {
     /// Return `true` if `PartialOrd` can be derived for this thing, `false`
@@ -121,6 +121,19 @@ pub trait CanDeriveEq {
                      -> bool;
 }
 
+/// A trait that encapsulates the logic for whether or not we can derive `Ord`
+/// for a given thing.
+///
+/// This should ideally be a no-op that just returns `true`, but instead needs
+/// to be a recursive method that checks whether all the proper members can
+/// derive ord or not, because of the limit rust has on 32 items as max in the
+/// array.
+pub trait CanDeriveOrd {
+    /// Return `true` if `Ord` can be derived for this thing, `false`
+    /// otherwise.
+    fn can_derive_ord(&self, ctx: &BindgenContext) -> bool;
+}
+
 /// A trait that encapsulates the logic for whether or not we can derive `Hash`.
 /// The difference between this trait and the CanDeriveHash is that the type
 /// implementing this trait cannot use recursion or lookup result from fix point

src/ir/item.rs

@@ -6,8 +6,8 @@ use super::comment;
 use super::comp::MethodKind;
 use super::context::{BindgenContext, ItemId, PartialType};
 use super::derive::{CanDeriveCopy, CanDeriveDebug, CanDeriveDefault,
-                    CanDeriveHash, CanDerivePartialOrd, CanDerivePartialEq,
-                    CanDeriveEq};
+                    CanDeriveHash, CanDerivePartialOrd, CanDeriveOrd,
+                    CanDerivePartialEq, CanDeriveEq};
 use super::dot::DotAttributes;
 use super::function::{Function, FunctionKind};
 use super::item_kind::ItemKind;
@@ -353,6 +353,14 @@ impl CanDeriveEq for Item {
     }
 }
 
+impl CanDeriveOrd for Item {
+    fn can_derive_ord(&self, ctx: &BindgenContext) -> bool {
+        ctx.options().derive_ord &&
+            ctx.lookup_item_id_can_derive_partialeq_or_partialord(self.id()) &&
+            !ctx.lookup_item_id_has_float(&self.id())
+    }
+}
+
 /// An item is the base of the bindgen representation, it can be either a
 /// module, a type, a function, or a variable (see `ItemKind` for more
 /// information).

src/lib.rs

@@ -265,6 +265,10 @@ impl Builder {
             output_vector.push("--with-derive-partialord".into());
         }
 
+        if self.options.derive_ord {
+            output_vector.push("--with-derive-ord".into());
+        }
+
         if self.options.derive_partialeq {
             output_vector.push("--with-derive-partialeq".into());
         }
@@ -819,7 +823,21 @@ impl Builder {
     }
 
     /// Set whether `PartialOrd` should be derived by default.
+    /// If we don't compute partialord, we also cannot compute
+    /// ord. Set the derive_ord to `false` when doit is `false`.
     pub fn derive_partialord(mut self, doit: bool) -> Self {
+        self.options.derive_partialord = doit;
+        if !doit {
+            self.options.derive_ord = false;
+        }
+        self
+    }
+
+    /// Set whether `Ord` should be derived by default.
+    /// We can't compute `Ord` without computing `PartialOrd`, 
+    /// so we set the same option to derive_partialord.
+    pub fn derive_ord(mut self, doit: bool) -> Self {
+        self.options.derive_ord = doit;
         self.options.derive_partialord = doit;
         self
     }
@@ -1190,6 +1208,10 @@ struct BindgenOptions {
     /// and types.
     derive_partialord: bool,
 
+    /// True if we should derive Ord trait implementations for C/C++ structures
+    /// and types.
+    derive_ord: bool,
+
     /// True if we should derive PartialEq trait implementations for C/C++ structures
     /// and types.
     derive_partialeq: bool,
@@ -1340,6 +1362,7 @@ impl Default for BindgenOptions {
             derive_default: false,
             derive_hash: false,
             derive_partialord: false,
+            derive_ord: false,
             derive_partialeq: false,
             derive_eq: false,
             enable_cxx_namespaces: false,

src/options.rs

@@ -88,7 +88,12 @@ where
                 .help("Derive partialord on any type."),
             Arg::with_name("with-derive-eq")
                 .long("with-derive-eq")
-                .help("Derive eq on any type. Enable this option also enables --with-derive-partialeq"),
+                .help("Derive eq on any type. Enable this option also \
+                       enables --with-derive-partialeq"),
+            Arg::with_name("with-derive-ord")
+                .long("with-derive-ord")
+                .help("Derive ord on any type. Enable this option also \
+                       enables --with-derive-partialord"),
             Arg::with_name("no-doc-comments")
                 .long("no-doc-comments")
                 .help("Avoid including doc comments in the output, see: \
@@ -351,6 +356,10 @@ where
         builder = builder.derive_eq(true);
     }
 
+    if matches.is_present("with-derive-ord") {
+        builder = builder.derive_ord(true);
+    }
+
     if matches.is_present("no-derive-default") {
         builder = builder.derive_default(false);
     }

tests/expectations/tests/derive-hash-struct-with-anon-struct-float.rs

@@ -5,7 +5,7 @@
 
 
 
-/// A struct containing a struct containing a float that cannot derive hash/eq but can derive partialeq and partialord
+/// A struct containing a struct containing a float that cannot derive Hash/Eq/Ord but can derive PartialEq/PartialOrd
 #[repr(C)]
 #[derive(Debug, Default, Copy, PartialOrd, PartialEq)]
 pub struct foo {

tests/expectations/tests/derive-hash-struct-with-float-array.rs

@@ -5,7 +5,7 @@
 
 
 
-/// A struct containing an array of floats that cannot derive hash/eq but can derive partialeq and partialord
+/// A struct containing an array of floats that cannot derive Hash/Eq/Ord but can derive PartialEq/PartialOrd
 #[repr(C)]
 #[derive(Debug, Default, Copy, PartialOrd, PartialEq)]
 pub struct foo {

tests/expectations/tests/derive-hash-struct-with-pointer.rs

@@ -5,9 +5,9 @@
 
 
 
-/// Pointers can derive Hash/PartialOrd/PartialEq/Eq
+/// Pointers can derive Hash/PartialOrd/Ord/PartialEq/Eq
 #[repr(C)]
-#[derive(Debug, Copy, Hash, PartialOrd, PartialEq, Eq)]
+#[derive(Debug, Copy, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct ConstPtrMutObj {
     pub bar: *const ::std::os::raw::c_int,
 }
@@ -45,7 +45,7 @@ impl Default for ConstPtrMutObj {
     }
 }
 #[repr(C)]
-#[derive(Debug, Copy, Hash, PartialOrd, PartialEq, Eq)]
+#[derive(Debug, Copy, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct MutPtrMutObj {
     pub bar: *mut ::std::os::raw::c_int,
 }
@@ -83,7 +83,7 @@ impl Default for MutPtrMutObj {
     }
 }
 #[repr(C)]
-#[derive(Debug, Copy, Hash, PartialOrd, PartialEq, Eq)]
+#[derive(Debug, Copy, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct MutPtrConstObj {
     pub bar: *const ::std::os::raw::c_int,
 }
@@ -121,7 +121,7 @@ impl Default for MutPtrConstObj {
     }
 }
 #[repr(C)]
-#[derive(Debug, Copy, Hash, PartialOrd, PartialEq, Eq)]
+#[derive(Debug, Copy, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct ConstPtrConstObj {
     pub bar: *const ::std::os::raw::c_int,
 }

tests/expectations/tests/derive-hash-template-def-float.rs

@@ -5,7 +5,7 @@
 
 
 
-/// Template definition containing a float, which cannot derive hash/eq but can derive partialeq and partialord.
+/// Template definition containing a float, which cannot derive Hash/Eq/Ord but can derive PartialEq/PartialOrd.
 #[repr(C)]
 #[derive(Debug, Copy, Clone, PartialOrd, PartialEq)]
 pub struct foo<T> {

tests/expectations/tests/derive-hash-template-inst-float.rs

@@ -5,9 +5,9 @@
 
 
 
-/// Template definition that doesn't contain float can derive hash/partialord/partialeq/eq
+/// Template definition that doesn't contain float can derive Hash/PartialOrd/Ord/PartialEq/Eq
 #[repr(C)]
-#[derive(Debug, Copy, Clone, Hash, PartialOrd, PartialEq, Eq)]
+#[derive(Debug, Copy, Clone, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct foo<T> {
     pub data: T,
     pub _phantom_0: ::std::marker::PhantomData<::std::cell::UnsafeCell<T>>,
@@ -17,9 +17,9 @@ impl<T> Default for foo<T> {
         unsafe { ::std::mem::zeroed() }
     }
 }
-/// Can derive hash/partialeq/eq when instantiated with int
+/// Can derive Hash/PartialOrd/Ord/PartialEq/Eq when instantiated with int
 #[repr(C)]
-#[derive(Debug, Copy, Hash, PartialOrd, PartialEq, Eq)]
+#[derive(Debug, Copy, Hash, PartialOrd, Ord, PartialEq, Eq)]
 pub struct IntStr {
     pub a: foo<::std::os::raw::c_int>,
 }
@@ -56,7 +56,7 @@ impl Default for IntStr {
         unsafe { ::std::mem::zeroed() }
     }
 }
-/// Cannot derive hash/eq when instantiated with float but can derive partialeq
+/// Cannot derive Hash/Eq/Ord when instantiated with float but can derive PartialEq/PartialOrd
 #[repr(C)]
 #[derive(Debug, Copy, PartialOrd, PartialEq)]
 pub struct FloatStr {

tests/headers/derive-hash-blacklisting.hpp

@@ -1,4 +1,4 @@
-// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-partialeq --with-derive-eq --whitelist-type 'Whitelisted.*' --blacklist-type Blacklisted --raw-line "#[repr(C)] #[derive(Debug, Hash, Copy, Clone, PartialEq, Eq)] pub struct Blacklisted<T> {t: T, pub _phantom_0: ::std::marker::PhantomData<::std::cell::UnsafeCell<T>> }"
+// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-ord --with-derive-partialeq --with-derive-eq --whitelist-type 'Whitelisted.*' --blacklist-type Blacklisted --raw-line "#[repr(C)] #[derive(Debug, Hash, Copy, Clone, PartialEq, Eq)] pub struct Blacklisted<T> {t: T, pub _phantom_0: ::std::marker::PhantomData<::std::cell::UnsafeCell<T>> }"
 //
 template <class T>
 struct Blacklisted {

tests/headers/derive-hash-struct-with-anon-struct-float.h

@@ -1,6 +1,6 @@
-// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-partialeq --with-derive-eq
+// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-ord --with-derive-partialeq --with-derive-eq
 //
-/// A struct containing a struct containing a float that cannot derive hash/eq but can derive partialeq and partialord
+/// A struct containing a struct containing a float that cannot derive Hash/Eq/Ord but can derive PartialEq/PartialOrd
 struct foo {
     struct {
         float a;

tests/headers/derive-hash-struct-with-float-array.h

@@ -1,6 +1,6 @@
-// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-partialeq --with-derive-eq
+// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-ord --with-derive-partialeq --with-derive-eq
 //
-/// A struct containing an array of floats that cannot derive hash/eq but can derive partialeq and partialord
+/// A struct containing an array of floats that cannot derive Hash/Eq/Ord but can derive PartialEq/PartialOrd
 struct foo {
     float bar[3];
 };

tests/headers/derive-hash-struct-with-pointer.h

@@ -1,6 +1,6 @@
-// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-partialeq --with-derive-eq
+// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-ord --with-derive-partialeq --with-derive-eq
 //
-/// Pointers can derive Hash/PartialOrd/PartialEq/Eq
+/// Pointers can derive Hash/PartialOrd/Ord/PartialEq/Eq
 struct ConstPtrMutObj {
     int* const bar;
 };

tests/headers/derive-hash-template-def-float.hpp

@@ -1,6 +1,6 @@
-// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-partialeq --with-derive-eq
+// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-ord --with-derive-partialeq --with-derive-eq
 //
-/// Template definition containing a float, which cannot derive hash/eq but can derive partialeq and partialord.
+/// Template definition containing a float, which cannot derive Hash/Eq/Ord but can derive PartialEq/PartialOrd.
 template <typename T>
 struct foo {
     T data;

tests/headers/derive-hash-template-inst-float.hpp

@@ -1,17 +1,17 @@
-// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-partialeq --with-derive-eq
+// bindgen-flags: --with-derive-hash --with-derive-partialord --with-derive-ord --with-derive-partialeq --with-derive-eq
 //
-/// Template definition that doesn't contain float can derive hash/partialord/partialeq/eq
+/// Template definition that doesn't contain float can derive Hash/PartialOrd/Ord/PartialEq/Eq
 template <typename T>
 struct foo {
     T data;
 };
 
-/// Can derive hash/partialeq/eq when instantiated with int
+/// Can derive Hash/PartialOrd/Ord/PartialEq/Eq when instantiated with int
 struct IntStr {
     foo<int> a;
 };
 
-/// Cannot derive hash/eq when instantiated with float but can derive partialeq
+/// Cannot derive Hash/Eq/Ord when instantiated with float but can derive PartialEq/PartialOrd
 struct FloatStr {
     foo<float> a;
 };