From 9771b45e0ead3fff4187b1674de9dc84d39dbda2 Mon Sep 17 00:00:00 2001
From: Alex Crichton <alex@alexcrichton.com>
Date: Wed, 5 Jul 2017 15:29:02 -0700
Subject: [PATCH] Add support for testing `str` consts

---
 src/lib.rs             | 73 +++++++++++++++++++++++++++++++++---------
 testcrate/src/t1.h     |  1 +
 testcrate/src/t1.rs    |  1 +
 testcrate/src/t2.h     |  1 +
 testcrate/src/t2.rs    |  1 +
 testcrate/tests/all.rs |  1 +
 6 files changed, 63 insertions(+), 15 deletions(-)

diff --git a/src/lib.rs b/src/lib.rs
index 1857d14..f476590 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -683,6 +683,9 @@ impl TestGenerator {
                 fn pretty(&self) -> String;
             }
 
+            impl<'a> Pretty for &'a str {
+                fn pretty(&self) -> String { format!("{:?}", self) }
+            }
             impl<T> Pretty for *const T {
                 fn pretty(&self) -> String { format!("{:?}", self) }
             }
@@ -994,6 +997,9 @@ impl<'a> Generator<'a> {
     }
 
     fn rust_ty_to_c_ty(&self, mut rust_ty: &str) -> String {
+        if rust_ty == "&str" {
+            return "char*".to_string();
+        }
         let mut cty = self.rust2c(&rust_ty.replace("*mut ", "")
                                           .replace("*const ", ""));
         while rust_ty.starts_with("*") {
@@ -1014,30 +1020,47 @@ impl<'a> Generator<'a> {
         }
 
         let cty = self.rust_ty_to_c_ty(rust_ty);
-
         t!(writeln!(self.c, r#"
             static {cty} __test_const_{name}_val = {name};
             {cty}* __test_const_{name}(void) {{
                 return &__test_const_{name}_val;
             }}
         "#, name = name, cty = cty));
-        t!(writeln!(self.rust, r#"
-            fn const_{name}() {{
-                extern {{
-                    fn __test_const_{name}() -> *const {ty};
+
+        if rust_ty == "&str" {
+            t!(writeln!(self.rust, r#"
+                fn const_{name}() {{
+                    extern {{
+                        fn __test_const_{name}() -> *const *const u8;
+                    }}
+                    let val = {name};
+                    unsafe {{
+                        let ptr = *__test_const_{name}();
+                        let c = ::std::ffi::CStr::from_ptr(ptr as *const _);
+                        let c = c.to_str().expect("const {name} not utf8");
+                        same(val, c, "{name} string");
+                    }}
                 }}
-                let val = {name};
-                unsafe {{
-                    let ptr1 = &val as *const _ as *const u8;
-                    let ptr2 = __test_const_{name}() as *const u8;
-                    for i in 0..mem::size_of::<{ty}>() {{
-                        let i = i as isize;
-                        same(*ptr1.offset(i), *ptr2.offset(i),
-                             &format!("{name} value at byte {{}}", i));
+            "#, name = name));
+        } else {
+            t!(writeln!(self.rust, r#"
+                fn const_{name}() {{
+                    extern {{
+                        fn __test_const_{name}() -> *const {ty};
+                    }}
+                    let val = {name};
+                    unsafe {{
+                        let ptr1 = &val as *const _ as *const u8;
+                        let ptr2 = __test_const_{name}() as *const u8;
+                        for i in 0..mem::size_of::<{ty}>() {{
+                            let i = i as isize;
+                            same(*ptr1.offset(i), *ptr2.offset(i),
+                                 &format!("{name} value at byte {{}}", i));
+                        }}
                     }}
                 }}
-            }}
-        "#, ty = rust_ty, name = name));
+            "#, ty = rust_ty, name = name));
+        }
         self.tests.push(format!("const_{}", name));
     }
 
@@ -1149,6 +1172,26 @@ impl<'a> Generator<'a> {
                 assert!(rust);
                 format!("[{}; {}]", self.ty2name(t, rust), self.expr2str(e))
             }
+            ast::TyKind::Rptr(_, ast::MutTy {
+                ref ty,
+                mutbl: ast::Mutability::Immutable,
+            }) => {
+                let path = match ty.node {
+                    ast::TyKind::Path(_, ref p) => p,
+                    _ => panic!("unknown ty {:?}", ty),
+                };
+                if path.segments.len() != 1 {
+                    panic!("unknown ty {:?}", ty)
+                }
+                if &*path.segments[0].identifier.name.as_str() != "str" {
+                    panic!("unknown ty {:?}", ty)
+                }
+                if rust {
+                    format!("&str")
+                } else {
+                    format!("char*")
+                }
+            }
             _ => panic!("unknown ty {:?}", ty),
         }
     }
diff --git a/testcrate/src/t1.h b/testcrate/src/t1.h
index 0fc6c0d..d32cd94 100644
--- a/testcrate/src/t1.h
+++ b/testcrate/src/t1.h
@@ -3,6 +3,7 @@
 typedef int32_t T1Foo;
 
 #define T1N 5
+#define T1S "foo"
 
 struct T1Bar {
   int32_t a;
diff --git a/testcrate/src/t1.rs b/testcrate/src/t1.rs
index a234840..0e48f0b 100644
--- a/testcrate/src/t1.rs
+++ b/testcrate/src/t1.rs
@@ -3,6 +3,7 @@
 use libc::*;
 
 pub type T1Foo = i32;
+pub const T1S: &'static str = "foo";
 
 pub const T1N: i32 = 5;
 
diff --git a/testcrate/src/t2.h b/testcrate/src/t2.h
index 85ac048..0ef984f 100644
--- a/testcrate/src/t2.h
+++ b/testcrate/src/t2.h
@@ -12,3 +12,4 @@ struct T2Baz {
 static void T2a(void) {}
 
 #define T2C 4
+#define T2S "a"
diff --git a/testcrate/src/t2.rs b/testcrate/src/t2.rs
index d68dd03..768f645 100644
--- a/testcrate/src/t2.rs
+++ b/testcrate/src/t2.rs
@@ -8,6 +8,7 @@ pub struct T2Baz {
 }
 
 pub const T2C: i32 = 5;
+pub const T2S: &'static str = "b";
 
 extern {
     pub fn T2a();
diff --git a/testcrate/tests/all.rs b/testcrate/tests/all.rs
index 32ddf18..a605366 100644
--- a/testcrate/tests/all.rs
+++ b/testcrate/tests/all.rs
@@ -35,6 +35,7 @@ fn t2() {
         "bad field type b of T2Baz",
         "bad T2a function pointer",
         "bad T2C value at byte 0",
+        "bad T2S string",
     ];
     let mut errors = errors.iter().cloned().collect::<HashSet<_>>();