Auto merge of #891 - fitzgen:fix-test-expectations, r=photoszzt

Fix test expectations

r? @photoszzt

cc @tmfink: I had to revert the target features commit because there were a bunch of compilation failures in the test expectations (we had another, earlier regression that accidentally made it so that we weren't compiling and running the test expectations in CI, so we didn't catch the target features PR's regressions).

7 files changed, 29 insertions, 261 deletions

diff --git a/src/codegen/mod.rs b/src/codegen/mod.rs
index ef6f031f..5c00a53d 100644
--- a/src/codegen/mod.rs
+++ b/src/codegen/mod.rs
@@ -350,7 +350,7 @@ impl CodeGenerator for Module {
             }
 
             if item.id() == ctx.root_module() {
-                if result.saw_union && !ctx.options().rust_features().untagged_union() {
+                if result.saw_union && !ctx.options().unstable_rust {
                     utils::prepend_union_types(ctx, &mut *result);
                 }
                 if result.saw_incomplete_array {
@@ -911,8 +911,8 @@ impl<'a> FieldCodegen<'a> for FieldData {
         let field_ty = ctx.resolve_type(self.ty());
         let ty = self.ty().to_rust_ty_or_opaque(ctx, &());
 
-        // NB: If supported, we use proper `union` types.
-        let ty = if parent.is_union() && !ctx.options().rust_features().untagged_union() {
+        // NB: In unstable rust we use proper `union` types.
+        let ty = if parent.is_union() && !ctx.options().unstable_rust {
             if ctx.options().enable_cxx_namespaces {
                 quote_ty!(ctx.ext_cx(), root::__BindgenUnionField<$ty>)
             } else {
@@ -1052,8 +1052,8 @@ impl BitfieldUnit {
                          -> P<ast::Item> {
         let ctor_name = self.ctor_name(ctx);
 
-        // If supported, add the const.
-        let fn_prefix = if ctx.options().rust_features().const_fn() {
+        // If we're generating unstable Rust, add the const.
+        let fn_prefix = if ctx.options().unstable_rust {
             quote_tokens!(ctx.ext_cx(), pub const fn)
         } else {
             quote_tokens!(ctx.ext_cx(), pub fn)
@@ -1115,8 +1115,8 @@ impl Bitfield {
         let offset = self.offset_into_unit();
         let mask = self.mask();
 
-        // If supported, add the const.
-        let fn_prefix = if ctx.options().rust_features().const_fn() {
+        // If we're generating unstable Rust, add the const.
+        let fn_prefix = if ctx.options().unstable_rust {
             quote_tokens!(ctx.ext_cx(), pub const fn)
         } else {
             quote_tokens!(ctx.ext_cx(), pub fn)
@@ -1445,7 +1445,7 @@ impl CodeGenerator for CompInfo {
         }
 
         let canonical_name = item.canonical_name(ctx);
-        let builder = if is_union && ctx.options().rust_features().untagged_union() {
+        let builder = if is_union && ctx.options().unstable_rust {
             aster::AstBuilder::new()
                 .item()
                 .pub_()
@@ -1552,7 +1552,7 @@ impl CodeGenerator for CompInfo {
                           ());
         }
 
-        if is_union && !ctx.options().rust_features().untagged_union() {
+        if is_union && !ctx.options().unstable_rust {
             let layout = layout.expect("Unable to get layout information?");
             let ty = BlobTyBuilder::new(layout).build();
             let field = StructFieldBuilder::named("bindgen_union_field")
diff --git a/src/features.rs b/src/features.rs
deleted file mode 100644
index ba2f11cf..00000000
--- a/src/features.rs
+++ /dev/null
@@ -1,187 +0,0 @@
-//! Contains code for selecting features
-
-#![deny(missing_docs)]
-#![deny(warnings)]
-#![deny(unused_extern_crates)]
-
-use std::io;
-use std::str::FromStr;
-
-/// Define RustTarget struct definition, Default impl, and conversions
-/// between RustTarget and String.
-macro_rules! rust_target_def {
-    ( $( $( #[$attr:meta] )* => $release:ident => $value:expr; )* ) => {
-        /// Represents the version of the Rust language to target.
-        ///
-        /// To support a beta release, use the corresponding stable release.
-        ///
-        /// This enum will have more variants added as necessary.
-        #[derive(Debug, Copy, Clone, Eq, PartialEq, PartialOrd, Hash)]
-        #[allow(non_camel_case_types)]
-        pub enum RustTarget {
-            $(
-                $(
-                    #[$attr]
-                )*
-                $release,
-            )*
-        }
-
-        impl Default for RustTarget {
-            /// Gives the latest stable Rust version
-            fn default() -> RustTarget {
-                LATEST_STABLE_RUST
-            }
-        }
-
-        impl FromStr for RustTarget {
-            type Err = io::Error;
-
-            #[allow(dead_code)]
-            /// Create a `RustTarget` from a string.
-            ///
-            /// * The stable/beta versions of Rust are of the form "1.0",
-            /// "1.19", etc.
-            /// * The nightly version should be specified with "nightly".
-            fn from_str(s: &str) -> Result<Self, Self::Err> {
-                match s.as_ref() {
-                    $(
-                        stringify!($value) => Ok(RustTarget::$release),
-                    )*
-                    _ => Err(
-                        io::Error::new(
-                            io::ErrorKind::InvalidInput,
-                            concat!(
-                                "Got an invalid rust target. Accepted values ",
-                                "are of the form ",
-                                "\"1.0\" or \"nightly\"."))),
-                }
-            }
-        }
-
-        impl From<RustTarget> for String {
-            fn from(target: RustTarget) -> Self {
-                match target {
-                    $(
-                        RustTarget::$release => stringify!($value),
-                    )*
-                }.into()
-            }
-        }
-    }
-}
-
-/// Defines an array slice with all RustTarget values
-macro_rules! rust_target_values_def {
-    ( $( $( #[$attr:meta] )* => $release:ident => $value:expr; )* ) => {
-        /// Strings of allowed `RustTarget` values
-        #[allow(dead_code)]
-        pub static RUST_TARGET_STRINGS: &'static [&str] = &[
-            $(
-                stringify!($value),
-            )*
-        ];
-    }
-}
-
-/// Defines macro which takes a macro
-macro_rules! rust_target_base {
-    ( $x_macro:ident ) => {
-        $x_macro!(
-            /// Rust stable 1.0
-            => Stable_1_0 => 1.0;
-            /// Rust stable 1.19
-            => Stable_1_19 => 1.19;
-            /// Nightly rust
-            => Nightly => nightly;
-        );
-    }
-}
-
-rust_target_base!(rust_target_def);
-rust_target_base!(rust_target_values_def);
-
-/// Latest stable release of Rust
-pub const LATEST_STABLE_RUST: RustTarget = RustTarget::Stable_1_19;
-
-/// Create RustFeatures struct definition, new(), and a getter for each field
-macro_rules! rust_feature_def {
-    ( $( $( #[$attr:meta] )* => $feature:ident; )* ) => {
-        /// Features supported by a rust target
-        #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
-        pub struct RustFeatures {
-            $(
-                $feature: bool,
-            )*
-        }
-
-        impl RustFeatures {
-            /// Gives a RustFeatures struct with all features disabled
-            fn new() -> Self {
-                RustFeatures {
-                    $(
-                        $feature: false,
-                    )*
-                }
-            }
-
-            $(
-                $(
-                    #[$attr]
-                )*
-                pub fn $feature(&self) -> bool {
-                    self.$feature
-                }
-            )*
-        }
-    }
-}
-
-rust_feature_def!(
-    /// Untagged unions ([RFC 1444](https://github.com/rust-lang/rfcs/blob/master/text/1444-union.md))
-    => untagged_union;
-    /// Constant function ([RFC 911](https://github.com/rust-lang/rfcs/blob/master/text/0911-const-fn.md))
-    => const_fn;
-);
-
-impl From<RustTarget> for RustFeatures {
-    fn from(rust_target: RustTarget) -> Self {
-        let mut features = RustFeatures::new();
-
-        if rust_target >= RustTarget::Stable_1_19 {
-            features.untagged_union = true;
-        }
-
-        if rust_target >= RustTarget::Nightly {
-            features.const_fn = true;
-        }
-
-        features
-    }
-}
-
-impl Default for RustFeatures {
-    fn default() -> Self {
-        let default_rust_target: RustTarget = Default::default();
-        Self::from(default_rust_target)
-    }
-}
-
-#[cfg(test)]
-mod test {
-    #![allow(unused_imports)]
-    use super::*;
-
-    fn test_target(target_str: &str, target: RustTarget) {
-        let target_string: String = target.into();
-        assert_eq!(target_str, target_string);
-        assert_eq!(target, RustTarget::from_str(target_str).unwrap());
-    }
-
-    #[test]
-    fn str_to_target() {
-        test_target("1.0", RustTarget::Stable_1_0);
-        test_target("1.19", RustTarget::Stable_1_19);
-        test_target("nightly", RustTarget::Nightly);
-    }
-}
diff --git a/src/ir/analysis/derive_copy.rs b/src/ir/analysis/derive_copy.rs
index dfd0343c..f4997632 100644
--- a/src/ir/analysis/derive_copy.rs
+++ b/src/ir/analysis/derive_copy.rs
@@ -207,7 +207,7 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveCopy<'ctx, 'gen> {
                 }
 
                 if info.kind() == CompKind::Union {
-                    if !self.ctx.options().rust_features().untagged_union() {
+                    if !self.ctx.options().unstable_rust {
                         // NOTE: If there's no template parameters we can derive copy
                         // unconditionally, since arrays are magical for rustc, and
                         // __BindgenUnionField always implements copy.
diff --git a/src/ir/analysis/derive_debug.rs b/src/ir/analysis/derive_debug.rs
index 8f2be22a..8990d1cc 100644
--- a/src/ir/analysis/derive_debug.rs
+++ b/src/ir/analysis/derive_debug.rs
@@ -208,7 +208,7 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDebug<'ctx, 'gen> {
                 );
 
                 if info.kind() == CompKind::Union {
-                    if self.ctx.options().rust_features().untagged_union() {
+                    if self.ctx.options().unstable_rust {
                         trace!("    cannot derive Debug for Rust unions");
                         return self.insert(id);
                     }
diff --git a/src/ir/analysis/derive_default.rs b/src/ir/analysis/derive_default.rs
index 4c2cad25..fe429e2a 100644
--- a/src/ir/analysis/derive_default.rs
+++ b/src/ir/analysis/derive_default.rs
@@ -242,7 +242,7 @@ impl<'ctx, 'gen> MonotoneFramework for CannotDeriveDefault<'ctx, 'gen> {
                 );
 
                 if info.kind() == CompKind::Union {
-                    if self.ctx.options().rust_features().untagged_union() {
+                    if self.ctx.options().unstable_rust {
                         trace!("    cannot derive Default for Rust unions");
                         return self.insert(id);
                     }
diff --git a/src/lib.rs b/src/lib.rs
index feb3c309..3a853829 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -62,7 +62,6 @@ macro_rules! doc_mod {
 }
 
 mod clang;
-mod features;
 mod ir;
 mod parse;
 mod regex_set;
@@ -73,7 +72,6 @@ pub mod callbacks;
 mod codegen;
 
 doc_mod!(clang, clang_docs);
-doc_mod!(features, features_docs);
 doc_mod!(ir, ir_docs);
 doc_mod!(parse, parse_docs);
 doc_mod!(regex_set, regex_set_docs);
@@ -82,8 +80,6 @@ mod codegen {
     include!(concat!(env!("OUT_DIR"), "/codegen.rs"));
 }
 
-pub use features::{RustTarget, LATEST_STABLE_RUST, RUST_TARGET_STRINGS};
-use features::RustFeatures;
 use ir::context::{BindgenContext, ItemId};
 use ir::item::Item;
 use parse::{ClangItemParser, ParseError};
@@ -192,8 +188,6 @@ impl Builder {
             output_vector.push(header);
         }
 
-        output_vector.push(self.options.rust_target.into());
-
         self.options
             .bitfield_enums
             .get_items()
@@ -346,6 +340,10 @@ impl Builder {
             output_vector.push("--no-prepend-enum-name".into());
         }
 
+        if !self.options.unstable_rust {
+            output_vector.push("--unstable-rust".into());
+        }
+
         self.options
             .opaque_types
             .get_items()
@@ -465,14 +463,6 @@ impl Builder {
         self
     }
 
-    /// Specify the rust target
-    ///
-    /// The default is the latest stable Rust version
-    pub fn rust_target(mut self, rust_target: RustTarget) -> Self {
-        self.options.set_rust_target(rust_target);
-        self
-    }
-
     /// Set the output graphviz file.
     pub fn emit_ir_graphviz<T: Into<String>>(mut self, path: T) -> Builder {
         let path = path.into();
@@ -754,10 +744,9 @@ impl Builder {
     }
 
     /// Avoid generating any unstable Rust, such as Rust unions, in the generated bindings.
-    #[deprecated(note="please use `rust_target` instead")]
-    pub fn unstable_rust(self, doit: bool) -> Self {
-        let rust_target = if doit { RustTarget::Nightly } else { LATEST_STABLE_RUST };
-        self.rust_target(rust_target)
+    pub fn unstable_rust(mut self, doit: bool) -> Self {
+        self.options.unstable_rust = doit;
+        self
     }
 
     /// Use core instead of libstd in the generated bindings.
@@ -966,6 +955,10 @@ pub struct BindgenOptions {
     /// and types.
     pub derive_default: bool,
 
+    /// True if we can use unstable Rust code in the bindings, false if we
+    /// cannot.
+    pub unstable_rust: bool,
+
     /// True if we should avoid using libstd to use libcore instead.
     pub use_core: bool,
 
@@ -1032,12 +1025,6 @@ pub struct BindgenOptions {
 
     /// Whether to prepend the enum name to bitfield or constant variants.
     pub prepend_enum_name: bool,
-
-    /// Version of the Rust compiler to target
-    rust_target: RustTarget,
-
-    /// Features to enable, derived from `rust_target`
-    rust_features: RustFeatures,
 }
 
 /// TODO(emilio): This is sort of a lie (see the error message that results from
@@ -1056,34 +1043,11 @@ impl BindgenOptions {
         self.constified_enum_modules.build();
         self.constified_enums.build();
     }
-
-    /// Update rust target version
-    pub fn set_rust_target(&mut self, rust_target: RustTarget) {
-        self.rust_target = rust_target;
-
-        // Keep rust_features synced with rust_target
-        self.rust_features = rust_target.into();
-    }
-
-    /// Get target Rust version
-    pub fn rust_target(&self) -> RustTarget {
-        self.rust_target
-    }
-
-    /// Get features supported by target Rust version
-    pub fn rust_features(&self) -> RustFeatures {
-        self.rust_features
-    }
-
 }
 
 impl Default for BindgenOptions {
     fn default() -> BindgenOptions {
-        let rust_target = RustTarget::default();
-
         BindgenOptions {
-            rust_target: rust_target,
-            rust_features: rust_target.into(),
             hidden_types: Default::default(),
             opaque_types: Default::default(),
             whitelisted_types: Default::default(),
@@ -1102,6 +1066,7 @@ impl Default for BindgenOptions {
             derive_default: false,
             enable_cxx_namespaces: false,
             disable_name_namespacing: false,
+            unstable_rust: false,
             use_core: false,
             ctypes_prefix: None,
             namespaced_constants: true,
diff --git a/src/options.rs b/src/options.rs
index e2e1b277..f2ed5494 100644
--- a/src/options.rs
+++ b/src/options.rs
@@ -1,9 +1,7 @@
-use bindgen::{Builder, CodegenConfig, RUST_TARGET_STRINGS, RustTarget, builder};
+use bindgen::{Builder, CodegenConfig, builder};
 use clap::{App, Arg};
-// use super::features::RUST_TARGET_STRINGS;
 use std::fs::File;
 use std::io::{self, Error, ErrorKind};
-use std::str::FromStr;
 
 /// Construct a new [`Builder`](./struct.Builder.html) from command line flags.
 pub fn builder_from_flags<I>
@@ -11,10 +9,6 @@ pub fn builder_from_flags<I>
      -> Result<(Builder, Box<io::Write>, bool), io::Error>
     where I: Iterator<Item = String>,
 {
-    let rust_target_help = format!(
-        "Version of the Rust compiler to target. Valid options are: {:?}.",
-        RUST_TARGET_STRINGS);
-
     let matches = App::new("bindgen")
         .version(env!("CARGO_PKG_VERSION"))
         .about("Generates Rust bindings from C/C++ headers.")
@@ -167,10 +161,6 @@ pub fn builder_from_flags<I>
                 .takes_value(true)
                 .multiple(true)
                 .number_of_values(1),
-            Arg::with_name("rust-target")
-                .long("rust-target")
-                .help(&rust_target_help)
-                .takes_value(true),
             Arg::with_name("static")
                 .long("static-link")
                 .help("Link to static library.")
@@ -236,10 +226,6 @@ pub fn builder_from_flags<I>
         return Err(Error::new(ErrorKind::Other, "Header not found"));
     }
 
-    if let Some(rust_target) = matches.value_of("rust-target") {
-        builder = builder.rust_target(RustTarget::from_str(rust_target)?);
-    }
-
     if let Some(bitfields) = matches.values_of("bitfield-enum") {
         for regex in bitfields {
             builder = builder.bitfield_enum(regex);
@@ -351,6 +337,10 @@ pub fn builder_from_flags<I>
         builder = builder.ignore_methods();
     }
 
+    if matches.is_present("unstable-rust") {
+        builder = builder.unstable_rust(true);
+    }
+
     if matches.is_present("no-convert-floats") {
         builder = builder.no_convert_floats();
     }