Auto merge of #859 - tmfink:feature-832-custom-rust-target, r=fitzgen

Feature 832 custom rust target

Addresses #832.

Instead of specifying whether or not to use stable, specify the Rust
release to support (one of several stable/beta releases or nightly).
The `--unstable-rust` option is still accepted and implies `--rust-target nightly`.

The definitions of `RustTarget` and `RustFeatures` are created with
macros.

In order to keep the test outputs the same,
`bindgen-flags: --rust-target 1.0` was added to test headers.

**Todo:**

- [x] Create `RustFeatures`/`RustTarget` structs
- [x] Replace uses of `unstable` with `RustFeatures` query
- [x] Add new tests
- [x] Fix doc comments TODOs

1 files changed, 44 insertions, 0 deletions

diff --git a/tests/headers/class_with_inner_struct_1_0.hpp b/tests/headers/class_with_inner_struct_1_0.hpp
new file mode 100644
index 00000000..5145337f
--- /dev/null
+++ b/tests/headers/class_with_inner_struct_1_0.hpp
@@ -0,0 +1,44 @@
+// bindgen-flags: --rust-target 1.0 -- -std=c++11
+
+
+class A {
+    unsigned c;
+    struct Segment { int begin, end; };
+    union {
+        int f;
+    } named_union;
+    union {
+        int d;
+    };
+};
+
+class B {
+    unsigned d;
+    struct Segment { int begin, end; };
+};
+
+
+enum class StepSyntax {
+    Keyword,                     // step-start and step-end
+    FunctionalWithoutKeyword,    // steps(...)
+    FunctionalWithStartKeyword,  // steps(..., start)
+    FunctionalWithEndKeyword,    // steps(..., end)
+};
+
+class C {
+    unsigned d;
+    union {
+        struct {
+            float mX1;
+            float mY1;
+            float mX2;
+            float mY2;
+        } mFunc;
+        struct {
+            StepSyntax mStepSyntax;
+            unsigned int mSteps;
+        };
+    };
+    // To ensure it doesn't collide
+    struct Segment { int begin, end; };
+};