Add params to Rust functions

7 files changed, 149 insertions, 7 deletions

diff --git a/hobgoblin/src/output/lang/rust/ast.hob b/hobgoblin/src/output/lang/rust/ast.hob
index 2b1871e..9a25ff2 100644
--- a/hobgoblin/src/output/lang/rust/ast.hob
+++ b/hobgoblin/src/output/lang/rust/ast.hob
@@ -40,6 +40,12 @@ struct RustEnumVariantTuple {
 
 struct RustFunction {
     field name: RustIdentifier;
+    field params: List[RustFunctionParam];
+}
+
+struct RustFunctionParam {
+    field name: RustIdentifier;
+    field type: RustType;
 }
 
 struct RustInherentImpl {
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 b751fae..432a4ba 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
@@ -114,7 +114,21 @@ public class RustWriter implements AutoCloseable {
     private void writeFunction(RustFunction function) throws IOException {
         this.writer.write("fn ");
         this.writeIdentifier(function.name());
-        this.writer.write("() {");
+        this.writer.write("(");
+
+        writeWithSeparator(
+            function.params(),
+            param -> {
+                this.writeIdentifier(param.name());
+                this.writer.write(": ");
+                this.writeType(param.type());
+            },
+            () -> {
+                this.writer.write(", ");
+            }
+        );
+
+        this.writer.write(") {");
         this.writer.newLine();
         this.writer.write("}");
     }
diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunction.java b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunction.java
index aea16f0..984aae4 100644
--- a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunction.java
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunction.java
@@ -5,22 +5,38 @@ package org.zwobble.hobgoblin.compiler.output.lang.rust.ast;
 // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction imports
 // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction imports
 
-public record RustFunction(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustAssociatedItem {
+public record RustFunction(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name, java.util.List<org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam> params) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustAssociatedItem {
     public static org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder arbitrary() {
-        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier.arbitrary().build());
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier.arbitrary().build(), java.util.List.of());
     }
 
-    public record Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustAssociatedItem.Builder {
+    public record Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name, java.util.List<org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam> params) implements org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustAssociatedItem.Builder {
         public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction build() {
-            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction(name);
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction(name, params);
         }
 
         public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder withName(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name) {
-            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(name);
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(name, params);
         }
 
         public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder withName(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier.Builder name) {
-            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(name.build());
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(name.build(), params);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder withParams(java.util.List<org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam> params) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(name, params);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder addParam(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam param) {
+            var params = new java.util.ArrayList<org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam>(this.params);
+            params.add(param);
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(name, params);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder addParam(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder param) {
+            var params = new java.util.ArrayList<org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam>(this.params);
+            params.add(param.build());
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder(name, params);
         }
 
         // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction.Builder body
diff --git a/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionParam.java b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionParam.java
new file mode 100644
index 0000000..f5ec692
--- /dev/null
+++ b/src/main/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionParam.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.RustFunctionParam imports
+// Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam imports
+
+public record RustFunctionParam(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType type) {
+    public static org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder arbitrary() {
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier.arbitrary().build(), org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustTypePath.arbitrary().build());
+    }
+
+    public record Builder(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name, org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType type) {
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam build() {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam(name, type);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder withName(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier name) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder(name, type);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder withName(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier.Builder name) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder(name.build(), type);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder withType(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType type) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder(name, type);
+        }
+
+        public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder withType(org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType.Builder type) {
+            return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder(name, type.build());
+        }
+
+        // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder body
+        // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam.Builder body
+    }
+
+    // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam body
+    // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam 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 1de04da..dd1729b 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
@@ -141,6 +141,21 @@ public class RustWriterTests {
     }
 
     @Test
+    public void functionWithParams() throws IOException {
+        var rust = RustFunction.arbitrary()
+            .withName(new RustIdentifier("area"))
+            .addParam(new RustFunctionParam(new RustIdentifier("width"), RustTypePath.of("i32")))
+            .addParam(new RustFunctionParam(new RustIdentifier("height"), RustTypePath.of("u64")))
+            .build();
+
+        var string = write(writer -> writer.writeAssociatedItem(rust));
+
+        assertThat(string, equalTo("""
+            fn area(width: i32, height: u64) {
+            }"""));
+    }
+
+    @Test
     public void emptyInherentImpl() throws IOException {
         var rust = RustInherentImpl.arbitrary().withType(RustTypePath.of("Square")).build();
 
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionMatcher.java b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionMatcher.java
index 4777b24..ac6d126 100644
--- a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionMatcher.java
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionMatcher.java
@@ -34,6 +34,12 @@ public class RustFunctionMatcher implements org.zwobble.precisely.Matcher<java.l
         return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionMatcher(submatchers);
     }
 
+    public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionMatcher withParams(org.zwobble.precisely.Matcher<? super java.util.List<org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam>> params) {
+        var submatchers = new java.util.ArrayList<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction>>(this.submatchers);
+        submatchers.add(org.zwobble.precisely.Matchers.has("params", org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunction::params, params));
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionMatcher(submatchers);
+    }
+
     // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionMatcher body
     // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionMatcher body
 }
diff --git a/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionParamMatcher.java b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionParamMatcher.java
new file mode 100644
index 0000000..64f7101
--- /dev/null
+++ b/src/test/java/org/zwobble/hobgoblin/compiler/output/lang/rust/ast/RustFunctionParamMatcher.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.RustFunctionParamMatcher imports
+// Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher imports
+
+public class RustFunctionParamMatcher implements org.zwobble.precisely.Matcher<java.lang.Object> {
+    public static org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher isRustFunctionParam() {
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher(java.util.List.of());
+    }
+
+    private final java.util.List<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam>> submatchers;
+
+    private RustFunctionParamMatcher(java.util.List<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam>> 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.RustFunctionParam.class, this.submatchers);
+    }
+
+    public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher withName(org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustIdentifier> name) {
+        var submatchers = new java.util.ArrayList<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam>>(this.submatchers);
+        submatchers.add(org.zwobble.precisely.Matchers.has("name", org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam::name, name));
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher(submatchers);
+    }
+
+    public org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher withType(org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustType> type) {
+        var submatchers = new java.util.ArrayList<org.zwobble.precisely.Matcher<? super org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam>>(this.submatchers);
+        submatchers.add(org.zwobble.precisely.Matchers.has("type", org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParam::type, type));
+        return new org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher(submatchers);
+    }
+
+    // Custom area start: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher body
+    // Custom area end: org.zwobble.hobgoblin.compiler.output.lang.rust.ast.RustFunctionParamMatcher body
+}