Add type cases to Rust AST

6 files changed, 117 insertions, 1 deletions

diff --git a/hobgoblin/src/output/lang/rust/ast.hob b/hobgoblin/src/output/lang/rust/ast.hob
index a592f4e..bce56f8 100644
--- a/hobgoblin/src/output/lang/rust/ast.hob
+++ b/hobgoblin/src/output/lang/rust/ast.hob
@@ -139,6 +139,7 @@ sum RustExpression {
     variant RustStructExpression;
     variant RustTryPropagationExpression;
     variant RustTupleExpression;
+    variant RustTypeCastExpression;
     variant RustVecRepeatExpression;
 }
 
@@ -249,6 +250,11 @@ struct RustTupleExpression {
     field elements: List[RustExpression];
 }
 
+struct RustTypeCastExpression {
+    field left: RustExpression;
+    field right: RustType;
+}
+
 struct RustVecRepeatExpression {
     field repeatOperand: RustExpression;
     field lengthOperand: RustExpression;
diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriter.java b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriter.java
index aa8d6cb..53b9a38 100644
--- a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriter.java
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriter.java
@@ -383,6 +383,10 @@ public class RustWriter implements AutoCloseable {
                 this.writeTupleExpression(tupleExpression);
             }
 
+            case RustTypeCastExpression typeCastExpression -> {
+                this.writeTypeCastExpression(typeCastExpression);
+            }
+
             case RustVecRepeatExpression vecRepeatExpression -> {
                 this.writeVecRepeatExpression(vecRepeatExpression);
             }
@@ -430,6 +434,7 @@ public class RustWriter implements AutoCloseable {
             case RustStructExpression _ -> RustPrecedence.PRIMARY;
             case RustTryPropagationExpression _ -> RustPrecedence.TRY_PROPAGATION;
             case RustTupleExpression _ -> RustPrecedence.PRIMARY;
+            case RustTypeCastExpression _ -> RustPrecedence.AS;
             case RustVecRepeatExpression _ -> RustPrecedence.PRIMARY;
         };
     }
@@ -668,6 +673,12 @@ public class RustWriter implements AutoCloseable {
         this.writer.write(")");
     }
 
+    private void writeTypeCastExpression(RustTypeCastExpression typeCastExpression) throws IOException {
+        this.writeSubExpression(typeCastExpression.left(), RustPrecedence.AS, true);
+        this.writer.write(" as ");
+        this.writeType(typeCastExpression.right());
+    }
+
     private void writeVecRepeatExpression(RustVecRepeatExpression vecRepeatExpression) throws IOException {
         this.writer.write("vec![");
         this.writeTopLevelExpression(vecRepeatExpression.repeatOperand());
diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustExpression.java b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustExpression.java
index 5f51d5e..9f15f5b 100644
--- a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustExpression.java
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustExpression.java
@@ -5,7 +5,7 @@ package org.zwobble.hobgoblin.compiler.output.lang.rust.ast;
 // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression imports
 // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression imports
 
-public sealed interface RustExpression permits org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustArrayRepeatExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBinaryExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBlockExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBoolLiteral, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustCallExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustClosureExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIfExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIntegerLiteral, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIteratorLoopExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustMatchExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustPath, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustPrefixExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustRangeExpr, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustStructExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTryPropagationExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTupleExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustVecRepeatExpression {
+public sealed interface RustExpression permits org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustArrayRepeatExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBinaryExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBlockExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBoolLiteral, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustCallExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustClosureExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIfExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIntegerLiteral, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIteratorLoopExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustMatchExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustPath, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustPrefixExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustRangeExpr, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustStructExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTryPropagationExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTupleExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustVecRepeatExpression {
     public interface Builder {
         public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression build();
 
diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustTypeCastExpression.java b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustTypeCastExpression.java
new file mode 100644
index 0000000..1a7e5bd
--- /dev/null
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustTypeCastExpression.java
@@ -0,0 +1,40 @@
+// Generated by hobgoblin.
+
+package org.zwobble.hobgoblin.compiler.output.lang.rust.ast;
+
+// Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression imports
+// Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression imports
+
+public record RustTypeCastExpression(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression left, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType right) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression {
+    public static org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder arbitrary() {
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBlockExpression.arbitrary().build(), org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustImplTraitType.arbitrary().build());
+    }
+
+    public record Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression left, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType right) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression.Builder {
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression build() {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression(left, right);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder withLeft(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression left) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder(left, right);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder withLeft(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression.Builder left) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder(left.build(), right);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder withRight(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType right) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder(left, right);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder withRight(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType.Builder right) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder(left, right.build());
+        }
+
+        // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder body
+        // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.Builder body
+    }
+
+    // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression body
+    // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression body
+}
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriterTests.java b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriterTests.java
index fe1f9b4..55c8f54 100644
--- a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriterTests.java
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/RustWriterTests.java
@@ -842,6 +842,20 @@ public class RustWriterTests {
         assertThat(string, equalTo("(a, b, c)"));
     }
 
+    // === Type cast expressions ===
+
+    @Test
+    public void typeCastExpression() throws IOException {
+        var rust = RustTypeCastExpression.arbitrary()
+            .withLeft(RustPath.of("a"))
+            .withRight(RustPath.of("X"))
+            .build();
+
+        var string = write(writer -> writer.writeTopLevelExpression(rust));
+
+        assertThat(string, equalTo("a as X"));
+    }
+
     // === Vec repeat expressions ===
 
     @Test
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustTypeCastExpressionMatcher.java b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustTypeCastExpressionMatcher.java
new file mode 100644
index 0000000..2ff190e
--- /dev/null
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustTypeCastExpressionMatcher.java
@@ -0,0 +1,45 @@
+// Generated by hobgoblin.
+
+package org.zwobble.hobgoblin.compiler.output.lang.rust.ast;
+
+// Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher imports
+// Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher imports
+
+public class RustTypeCastExpressionMatcher implements org.zwobble.precisely.Matcher<java.lang.Object> {
+    public static org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher isRustTypeCastExpression() {
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher(java.util.List.of());
+    }
+
+    private final java.util.List<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression>> submatchers;
+
+    private RustTypeCastExpressionMatcher(java.util.List<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression>> submatchers) {
+        this.submatchers = submatchers;
+    }
+
+    public org.zwobble.precisely.MatchResult match(java.lang.Object actual) {
+        return this.toMatcher().match(actual);
+    }
+
+    public org.zwobble.precisely.TextTree describe() {
+        return this.toMatcher().describe();
+    }
+
+    private org.zwobble.precisely.Matcher<java.lang.Object> toMatcher() {
+        return org.zwobble.precisely.Matchers.instanceOf(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression.class, this.submatchers);
+    }
+
+    public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher withLeft(org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression> left) {
+        var submatchers = new java.util.ArrayList<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression>>(this.submatchers);
+        submatchers.add(org.zwobble.precisely.Matchers.has("left", org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression::left, left));
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher(submatchers);
+    }
+
+    public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher withRight(org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType> right) {
+        var submatchers = new java.util.ArrayList<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression>>(this.submatchers);
+        submatchers.add(org.zwobble.precisely.Matchers.has("right", org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpression::right, right));
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher(submatchers);
+    }
+
+    // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher body
+    // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypeCastExpressionMatcher body
+}