Add windows-bindgen warning when rustfmt fails (#3778)

Author: kennykerr

crates/libs/bindgen/src/config/format.rs

@@ -23,6 +23,16 @@ impl Config<'_> {
         };
         let tokens = format!("{preamble}{allow}{tokens}");
 
+        if let Some(result) = self.rustfmt(&tokens) {
+            result
+        } else {
+            self.warnings
+                .add("failed to format output with `rustfmt`".to_string());
+            tokens
+        }
+    }
+
+    fn rustfmt(&self, tokens: &str) -> Option<String> {
         let mut cmd = std::process::Command::new("rustfmt");
         cmd.stdin(std::process::Stdio::piped());
         cmd.stdout(std::process::Stdio::piped());
@@ -33,32 +43,16 @@ impl Config<'_> {
             cmd.arg(self.rustfmt);
         }
 
-        let Ok(mut child) = cmd.spawn() else {
-            return tokens;
-        };
-
-        let Some(mut stdin) = child.stdin.take() else {
-            return tokens;
-        };
-
-        if stdin.write_all(tokens.as_bytes()).is_err() {
-            return tokens;
-        }
-
+        let mut child = cmd.spawn().ok()?;
+        let mut stdin = child.stdin.take()?;
+        stdin.write_all(tokens.as_bytes()).ok()?;
         drop(stdin);
-
-        let Ok(output) = child.wait_with_output() else {
-            return tokens;
-        };
+        let output = child.wait_with_output().ok()?;
 
         if !output.status.success() {
-            return tokens;
+            return None;
         }
 
-        if let Ok(result) = String::from_utf8(output.stdout) {
-            result
-        } else {
-            tokens
-        }
+        String::from_utf8(output.stdout).ok()
     }
 }

crates/tests/libs/bindgen/src/lib.rs

@@ -1,5 +1,6 @@
 // This package was generated by `tool_bindgen`.
 
+#[rustfmt::skip] pub mod rustfmt_25;
 pub mod bool;
 pub mod bool_event;
 pub mod bool_event_sans_reference;

crates/tests/libs/bindgen/src/rustfmt_25.rs

@@ -0,0 +1,12 @@
+#[repr(C)]
+#[derive(
+    Clone,
+    Copy,
+    Debug,
+    Default,
+    PartialEq,
+)]
+pub struct POINT {
+    pub x: i32,
+    pub y: i32,
+}

crates/tests/libs/bindgen/tests/panic.rs

@@ -182,3 +182,20 @@ fn skip_method() {
     ])
     .unwrap();
 }
+
+#[test]
+#[should_panic(expected = "failed to format output with `rustfmt`")]
+fn rustfmt_failure() {
+    let mut path = std::env::temp_dir();
+    path.push("rustfmt_failure");
+
+    windows_bindgen::bindgen([
+        "--out",
+        &path.to_string_lossy(),
+        "--rustfmt",
+        "fail=true",
+        "--filter",
+        "POINT",
+    ])
+    .unwrap();
+}

crates/tools/bindgen/src/main.rs

@@ -176,6 +176,9 @@ fn main() {
         "--out comment_no_allow.rs --in default --filter GetTickCount --sys --flat --no-allow",
     );
 
+    // Tests for rustfmt
+    bindgen("--out rustfmt_25.rs --rustfmt max_width=25,newline_style=Unix --filter POINT --flat --no-comment --no-allow".split_whitespace()).unwrap();
+
     write_lib();
     println!("Finished in {:.2}s", time.elapsed().as_secs_f32());
 }
@@ -185,7 +188,7 @@ fn main() {
 // those modules.
 
 fn write_lib() {
-    let mods = std::fs::read_dir(".")
+    let mut mods: Vec<String> = std::fs::read_dir(".")
         .unwrap()
         .flatten()
         .filter_map(|entry| {
@@ -195,13 +198,21 @@ fn write_lib() {
 
                 if path == "lib.rs" {
                     None
+                } else if path.starts_with("rustfmt") {
+                    Some(format!(
+                        "\n#[rustfmt::skip] pub mod {};",
+                        path.strip_suffix(".rs").unwrap()
+                    ))
                 } else {
                     Some(format!("\npub mod {};", path.strip_suffix(".rs").unwrap()))
                 }
             } else {
                 None
             }
-        });
+        })
+        .collect();
+
+    mods.sort();
 
     let mut lib_rs = "// This package was generated by `tool_bindgen`.\n".to_string();
     lib_rs.extend(mods);