Add field expressions to Rust AST

6 files changed, 122 insertions, 1 deletions

diff --git a/hobgoblin/src/output/lang/rust/ast.hob b/hobgoblin/src/output/lang/rust/ast.hob
index 9c29cab..970ae7f 100644
--- a/hobgoblin/src/output/lang/rust/ast.hob
+++ b/hobgoblin/src/output/lang/rust/ast.hob
@@ -117,6 +117,7 @@ sum RustExpression {
     variant RustBlockExpression;
     variant RustBoolLiteral;
     variant RustCallExpression;
+    variant RustFieldExpression;
     variant RustPathInExpression;
 }
 
@@ -134,6 +135,11 @@ struct RustCallExpression {
     field args: List[RustExpression];
 }
 
+struct RustFieldExpression {
+    field containerOperand: RustExpression;
+    field fieldName: RustIdentifier;
+}
+
 // == Types ==
 
 sum RustType {
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 665a056..5a29448 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
@@ -305,6 +305,10 @@ public class RustWriter implements AutoCloseable {
                 this.writeCallExpression(callExpression);
             }
 
+            case RustFieldExpression fieldExpression -> {
+                this.writeFieldExpression(fieldExpression);
+            }
+
             case RustPathInExpression pathInExpression -> {
                 this.writePathInExpression(pathInExpression);
             }
@@ -347,6 +351,12 @@ public class RustWriter implements AutoCloseable {
         this.writer.write(")");
     }
 
+    private void writeFieldExpression(RustFieldExpression fieldExpression) throws IOException {
+        this.writeExpression(fieldExpression.containerOperand());
+        this.writer.write(".");
+        this.writeIdentifier(fieldExpression.fieldName());
+    }
+
     // == Types ==
 
     void writeType(RustType type) throws IOException {
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 4fea607..f850a72 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.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.RustPathInExpression {
+public sealed interface RustExpression permits 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.RustFieldExpression, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustPathInExpression {
     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/RustFieldExpression.java b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFieldExpression.java
new file mode 100644
index 0000000..12e86f3
--- /dev/null
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFieldExpression.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.RustFieldExpression imports
+// Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression imports
+
+public record RustFieldExpression(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression containerOperand, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier fieldName) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression {
+    public static org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder arbitrary() {
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustBlockExpression.arbitrary().build(), org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier.arbitrary().build());
+    }
+
+    public record Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression containerOperand, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier fieldName) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression.Builder {
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression build() {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression(containerOperand, fieldName);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder withContainerOperand(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression containerOperand) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder(containerOperand, fieldName);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder withContainerOperand(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression.Builder containerOperand) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder(containerOperand.build(), fieldName);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder withFieldName(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier fieldName) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder(containerOperand, fieldName);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder withFieldName(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier.Builder fieldName) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder(containerOperand, fieldName.build());
+        }
+
+        // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder body
+        // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression.Builder body
+    }
+
+    // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression body
+    // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression 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 da07c8a..21f8833 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
@@ -351,6 +351,8 @@ public class RustWriterTests {
 
     // == Expressions ==
 
+    // === Block expressions ===
+
     @Test
     public void blockExpressionWithNoStatementsAndNoFinalOperand() throws IOException {
         var rust = RustBlockExpression.arbitrary().build();
@@ -418,6 +420,8 @@ public class RustWriterTests {
             }"""));
     }
 
+    // === Boolean literals ===
+
     @Test
     public void trueLiteral() throws IOException {
         var rust = RustBoolLiteral.arbitrary().withValue(true).build();
@@ -436,6 +440,8 @@ public class RustWriterTests {
         assertThat(string, equalTo("false"));
     }
 
+    // === Call expressions ===
+
     @Test
     public void callExpressionWithNoArgs() throws IOException {
         var rust = RustCallExpression.arbitrary()
@@ -460,6 +466,20 @@ public class RustWriterTests {
         assertThat(string, equalTo("f(x, y)"));
     }
 
+    // === Field expressions ===
+
+    @Test
+    public void fieldExpression() throws IOException {
+        var rust = RustFieldExpression.arbitrary()
+            .withContainerOperand(RustPathInExpression.of("x"))
+            .withFieldName(RustIdentifier.of("y"))
+            .build();
+
+        var string = write(writer -> writer.writeExpression(rust));
+
+        assertThat(string, equalTo("x.y"));
+    }
+
     // == Types ==
 
     @Test
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFieldExpressionMatcher.java b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFieldExpressionMatcher.java
new file mode 100644
index 0000000..ce26347
--- /dev/null
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFieldExpressionMatcher.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.RustFieldExpressionMatcher imports
+// Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher imports
+
+public class RustFieldExpressionMatcher implements org.zwobble.precisely.Matcher<java.lang.Object> {
+    public static org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher isRustFieldExpression() {
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher(java.util.List.of());
+    }
+
+    private final java.util.List<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression>> submatchers;
+
+    private RustFieldExpressionMatcher(java.util.List<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression>> 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.RustFieldExpression.class, this.submatchers);
+    }
+
+    public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher withContainerOperand(org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustExpression> containerOperand) {
+        var submatchers = new java.util.ArrayList<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression>>(this.submatchers);
+        submatchers.add(org.zwobble.precisely.Matchers.has("containerOperand", org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression::containerOperand, containerOperand));
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher(submatchers);
+    }
+
+    public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher withFieldName(org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier> fieldName) {
+        var submatchers = new java.util.ArrayList<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression>>(this.submatchers);
+        submatchers.add(org.zwobble.precisely.Matchers.has("fieldName", org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpression::fieldName, fieldName));
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher(submatchers);
+    }
+
+    // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher body
+    // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFieldExpressionMatcher body
+}