Use windows-core with embedded bindings via windows-bindgen

.github/workflows/rust.yml

@@ -369,3 +369,15 @@ jobs:
           tool: cargo-hack
 
       - run: cargo hack check --version-range 1.36.. --version-step 2 --clean-per-version --clean-per-run
+
+  generate-windows-bindings:
+    name: Generate windows-core bindings with windows-bindgen
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Clean
+        run: rm -rf src/Windows.rs
+      - name: Generate
+        run: cargo r --manifest-path=api_gen/Cargo.toml
+      - name: Diff generated Rust code
+        run: test -z "$(git status --porcelain)" || (echo "::error::Generated files are different, please regenerate with cargo run --manifest-path=api_gen/Cargo.toml!"; git status; false)

Cargo.toml

@@ -6,7 +6,7 @@ authors = [
     "Andrew Straw <strawman@astraw.com>",
     "René Kijewski <rene.kijewski@fu-berlin.de>",
     "Ryan Lopopolo <rjl@hyperbo.la>",
-    ]
+]
 repository = "https://github.com/strawlab/iana-time-zone"
 license = "MIT OR Apache-2.0"
 keywords = ["IANA", "time"]
@@ -25,7 +25,7 @@ android_system_properties = "0.1.5"
 core-foundation-sys = "0.8.3"
 
 [target.'cfg(target_os = "windows")'.dependencies]
-windows = { version = "0.48.0", features = [ "Globalization" ] }
+windows-core = { version = ">=0.50, <=0.51" }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 js-sys = "0.3.50"

api_gen/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "api_gen"
+version = "0.0.0"
+edition = "2018"
+publish = false
+
+[dependencies]
+windows-bindgen = "0.51"
+
+# Dissociate this crate from the root workspace to allow older Rust to build the main crate within
+# the workspace, without observing `edition = "2021"` inside `windows-bindgen`.
+[workspace]

api_gen/src/main.rs

@@ -0,0 +1,7 @@
+use windows_bindgen::{bindgen, Result};
+
+fn main() -> Result<()> {
+    let log = bindgen(["--etc", "bindings.txt"])?;
+    println!("{}", log);
+    Ok(())
+}

bindings.txt

@@ -0,0 +1,16 @@
+--out src/Windows.rs
+
+--filter
+    Windows.Globalization.Calendar
+
+    # Dependencies of the above
+    Windows.Foundation.Collections.IIterable
+    Windows.Foundation.Collections.IIterator
+    Windows.Foundation.Collections.IVectorView
+    Windows.Foundation.DateTime
+    Windows.Foundation.TimeSpan
+    Windows.Globalization.DayOfWeek
+    Windows.Globalization.ICalendar
+    Windows.Globalization.ICalendarFactory
+    Windows.Globalization.ICalendarFactory2
+    Windows.Globalization.ITimeZoneOnCalendar