Simplify Array usage with non-WinRT types (#2362)

.github/workflows/clippy.yml

@@ -67,6 +67,7 @@ jobs:
           cargo clippy -p test_alternate_success_code &&
           cargo clippy -p test_arch &&
           cargo clippy -p test_arch_feature &&
+          cargo clippy -p test_array &&
           cargo clippy -p test_bcrypt &&
           cargo clippy -p test_bstr &&
           cargo clippy -p test_calling_convention &&

.github/workflows/test.yml

@@ -117,6 +117,7 @@ jobs:
           cargo test --target ${{ matrix.target }} -p test_alternate_success_code &&
           cargo test --target ${{ matrix.target }} -p test_arch &&
           cargo test --target ${{ matrix.target }} -p test_arch_feature &&
+          cargo test --target ${{ matrix.target }} -p test_array &&
           cargo test --target ${{ matrix.target }} -p test_bcrypt &&
           cargo test --target ${{ matrix.target }} -p test_bstr &&
           cargo test --target ${{ matrix.target }} -p test_calling_convention &&

crates/libs/windows/src/core/array.rs

@@ -54,6 +54,18 @@ impl<T: Type<T>> Array<T> {
         array
     }
 
+    /// Creates an array from a pointer and length. The `len` argument is the number of elements, not the number of bytes.
+    /// # Safety
+    /// The `data` argument must have been allocated with `CoTaskMemAlloc`.
+    pub unsafe fn from_raw_parts(data: *mut T::Default, len: u32) -> Self {
+        Self { data, len }
+    }
+
+    /// Returns a slice containing the entire array.
+    pub fn as_slice(&self) -> &[T::Default] {
+        self
+    }
+
     /// Returns `true` if the array is empty.
     pub fn is_empty(&self) -> bool {
         self.len == 0

crates/tests/array/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "test_array"
+version = "0.0.0"
+authors = ["Microsoft"]
+edition = "2018"
+
+[dependencies.windows]
+path = "../../libs/windows"
+features = [
+    "Foundation",
+    "Win32_Media_MediaFoundation",
+]

crates/tests/array/src/lib.rs

@@ -0,0 +1 @@
+

crates/tests/array/tests/com.rs

@@ -0,0 +1,19 @@
+use windows::{core::*, Win32::Media::MediaFoundation::*};
+
+#[test]
+fn test() -> Result<()> {
+    unsafe {
+        let mut data = std::ptr::null_mut();
+        let mut len = 0;
+
+        MFTEnumEx(MFT_CATEGORY_VIDEO_ENCODER, MFT_ENUM_FLAG_HARDWARE, None, None, &mut data, &mut len)?;
+
+        let array = Array::<IMFActivate>::from_raw_parts(data as _, len);
+
+        for i in array.as_slice() {
+            println!("{}", i.as_ref().unwrap().GetCount()?);
+        }
+
+        Ok(())
+    }
+}

crates/tests/array/tests/primitive.rs

@@ -0,0 +1,30 @@
+use windows::core::Array;
+
+#[test]
+fn array() {
+    let a = Array::<i32>::new();
+    assert!(a.is_empty());
+
+    let mut a = Array::<i32>::with_len(3);
+    assert_eq!(a[0], 0);
+    assert_eq!(a[1], 0);
+    assert_eq!(a[2], 0);
+
+    a[0] = 1;
+    a[1] = 2;
+    a[2] = 3;
+
+    assert_eq!(a[0], 1);
+    assert_eq!(a[1], 2);
+    assert_eq!(a[2], 3);
+
+    let result = a.as_slice().iter().fold(0, |acc, x| acc + x);
+    assert_eq!(result, 6);
+
+    let a = Array::<i32>::from_slice(&[4, 5, 6]);
+
+    assert_eq!(a.len(), 3);
+    assert_eq!(a[0], 4);
+    assert_eq!(a[1], 5);
+    assert_eq!(a[2], 6);
+}

crates/tests/winrt/tests/array.rs → crates/tests/array/tests/winrt.rs

@@ -13,8 +13,6 @@ fn array() {
     a[0] = Uri::CreateUri(&windows::core::HSTRING::from("http://kennykerr.ca")).ok();
     a[1] = Uri::CreateUri(&windows::core::HSTRING::from("http://microsoft.com")).ok();
 
-    // TODO: this seems rather tedious... may warrant a windows::Option<T> that's more convenient
-    // that could handle both nullable and IReference<T> behaviors in a single abstraction.
     assert!(a[0].as_ref().unwrap().Domain().unwrap() == "kennykerr.ca");
     assert!(a[1].as_ref().unwrap().Domain().unwrap() == "microsoft.com");
 }