Add if instruction

2 files changed, 36 insertions, 0 deletions

diff --git a/src/test/java/org/shedlang/compiler/stackir/InstructionSerializerTests.java b/src/test/java/org/shedlang/compiler/stackir/InstructionSerializerTests.java
index 3ce690b2..72056a3e 100644
--- a/src/test/java/org/shedlang/compiler/stackir/InstructionSerializerTests.java
+++ b/src/test/java/org/shedlang/compiler/stackir/InstructionSerializerTests.java
@@ -76,6 +76,35 @@ public class InstructionSerializerTests {
     }
 
     @Test
+    public void canSerializeIf() {
+        var instruction = Instructions.if_(
+            List.of(
+                Instructions.pushUnit()
+            ),
+            List.of(
+                Instructions.localLoad("x"),
+                Instructions.discard(),
+                Instructions.pushBool(true)
+            )
+        );
+
+        var string = serialize(instruction);
+
+        assertThat(string, equalTo("""
+            (
+                if
+                (
+                    (push-unit)
+                )
+                (
+                    (local-load "x")
+                    (discard)
+                    (push-bool true)
+                )
+            )"""));
+    }
+
+    @Test
     public void canSerializeIntAdd() {
         var instruction = Instructions.intAdd();
 
diff --git a/src/test/java/org/shedlang/compiler/stackir/instructions/Instructions.java b/src/test/java/org/shedlang/compiler/stackir/instructions/Instructions.java
index df8b193b..131207b8 100644
--- a/src/test/java/org/shedlang/compiler/stackir/instructions/Instructions.java
+++ b/src/test/java/org/shedlang/compiler/stackir/instructions/Instructions.java
@@ -22,6 +22,13 @@ public class Instructions {
         return new FieldLoadInstruction(namespaceName, fieldName, Sources.NULL);
     }
 
+    public static Instruction if_(
+        List<Instruction> trueBody,
+        List<Instruction> falseBody
+    ) {
+        return new IfInstruction(trueBody, falseBody, Sources.NULL);
+    }
+
     public static Instruction intAdd() {
         return new IntAddInstruction(Sources.NULL);
     }