Clippy fixes.

engine/src/conversion/parse/parse_bindgen.rs

@@ -253,12 +253,11 @@ impl<'a> ParseBindgen<'a> {
                             let old_id = &urn.ident;
                             let new_id = &urn.rename;
                             let new_tyname = QualifiedName::new(ns, new_id.clone());
-                            if segs.remove(0) != "self" {
-                                panic!("Path didn't start with self");
-                            }
-                            if segs.remove(0) != "super" {
-                                panic!("Path didn't start with self::super");
-                            }
+                            assert!(segs.remove(0) == "self", "Path didn't start with self");
+                            assert!(
+                                segs.remove(0) == "super",
+                                "Path didn't start with self::super"
+                            );
                             // This is similar to the path encountered within 'tree'
                             // but without the self::super prefix which is unhelpful
                             // in our output mod, because we prefer relative paths

engine/src/lib.rs

@@ -261,9 +261,10 @@ impl IncludeCppEngine {
     }
 
     pub fn config_mut(&mut self) -> &mut IncludeCppConfig {
-        if !matches!(self.state, State::NotGenerated) {
-            panic!("Can't alter config after generation commenced");
-        }
+        assert!(
+            matches!(self.state, State::NotGenerated),
+            "Can't alter config after generation commenced"
+        );
         &mut self.config
     }
 
@@ -562,9 +563,7 @@ pub fn preprocess(
     cmd.arg(listing_path.to_str().unwrap());
     cmd.stderr(Stdio::inherit());
     let result = cmd.output().expect("failed to execute clang++");
-    if !result.status.success() {
-        panic!("failed to preprocess");
-    }
+    assert!(result.status.success(), "failed to preprocess");
     let mut file = File::create(preprocess_path)?;
     file.write_all(&result.stdout)?;
     Ok(())