From f21a37786b0f3c6bda3f9fe8b756f58175e6da92 Mon Sep 17 00:00:00 2001
From: Andrew Druk <adruk@readdle.com>
Date: Sat, 30 Jan 2021 20:02:06 +0200
Subject: [PATCH] Dev: fix primitive optional return types

---
 .../com/readdle/codegen/SwiftEnvironment.java | 27 ++++++++++++++
 .../readdle/codegen/SwiftFuncDescriptor.java  | 36 ++++++++++++++++---
 2 files changed, 59 insertions(+), 4 deletions(-)

diff --git a/compiler/src/main/java/com/readdle/codegen/SwiftEnvironment.java b/compiler/src/main/java/com/readdle/codegen/SwiftEnvironment.java
index 5f3faf3..7e95ba3 100644
--- a/compiler/src/main/java/com/readdle/codegen/SwiftEnvironment.java
+++ b/compiler/src/main/java/com/readdle/codegen/SwiftEnvironment.java
@@ -151,6 +151,33 @@ Type makeUnsigned() {
                     throw new IllegalStateException(swiftType + " can't be unsigned");
             }
         }
+
+        public String primitiveDefaultValue() {
+            switch (swiftType) {
+                case "Bool":
+                    return "jboolean(JNI_FALSE)";
+                case "Int":
+                case "Int32":
+                case "UInt":
+                case "UInt32":
+                    return "jint(0)";
+                case "Int8":
+                case "UInt8":
+                    return "jbyte(0)";
+                case "Int16":
+                case "UInt16":
+                    return "jshort(0)";
+                case "Int64":
+                case "UInt64":
+                    return "jlong(0)";
+                case "Float":
+                    return "jfloat(0)";
+                case "Double":
+                    return "jdouble(0)";
+                default:
+                    throw new IllegalStateException(swiftType + " is not primitive");
+            }
+        }
     }
 
 }
diff --git a/compiler/src/main/java/com/readdle/codegen/SwiftFuncDescriptor.java b/compiler/src/main/java/com/readdle/codegen/SwiftFuncDescriptor.java
index 57836aa..7b58bc6 100644
--- a/compiler/src/main/java/com/readdle/codegen/SwiftFuncDescriptor.java
+++ b/compiler/src/main/java/com/readdle/codegen/SwiftFuncDescriptor.java
@@ -99,7 +99,10 @@ public void generateCode(SwiftWriter swiftWriter, String javaFullName, String sw
 
         String retType = "";
         if (returnSwiftType != null) {
-            retType = " -> " + returnSwiftType.javaSigType(isReturnTypeOptional) + "?";
+            retType = " -> " + returnSwiftType.javaSigType(isReturnTypeOptional);
+            if (isReturnTypeOptional || !returnSwiftType.isPrimitiveType()) {
+                retType += "?";
+            }
         }
 
         swiftWriter.emit(String.format(")%s {\n", retType));
@@ -143,7 +146,17 @@ else if (param.isOptional) {
             swiftWriter.emitStatement("}");
             swiftWriter.emitStatement("catch {");
             Utils.handleRuntimeError(swiftWriter);
-            swiftWriter.emitStatement(String.format("return%s", returnSwiftType != null ? " nil" : ""));
+            if (returnSwiftType == null) {
+                swiftWriter.emitStatement("return");
+            }
+            else {
+                if (!isReturnTypeOptional && returnSwiftType.isPrimitiveType()) {
+                    swiftWriter.emitStatement("return " + returnSwiftType.primitiveDefaultValue());
+                }
+                else {
+                    swiftWriter.emitStatement("return nil");
+                }
+            }
             swiftWriter.emitStatement("}");
         }
 
@@ -192,7 +205,12 @@ else if (param.isOptional) {
             swiftWriter.emitStatement("}");
             swiftWriter.emitStatement("catch {");
             Utils.handleRuntimeError(swiftWriter);
-            swiftWriter.emitStatement("return nil");
+            if (!isReturnTypeOptional && returnSwiftType.isPrimitiveType()) {
+                swiftWriter.emitStatement("return " + returnSwiftType.primitiveDefaultValue());
+            }
+            else {
+                swiftWriter.emitStatement("return nil");
+            }
             swiftWriter.emitStatement("}");
         }
 
@@ -200,7 +218,17 @@ else if (param.isOptional) {
             swiftWriter.emitStatement("}");
             swiftWriter.emitStatement("catch {");
             Utils.handleError(swiftWriter);
-            swiftWriter.emitStatement(String.format("return%s", returnSwiftType != null ? " nil" : ""));
+            if (returnSwiftType == null) {
+                swiftWriter.emitStatement("return");
+            }
+            else {
+                if (!isReturnTypeOptional && returnSwiftType.isPrimitiveType()) {
+                    swiftWriter.emitStatement("return " + returnSwiftType.primitiveDefaultValue());
+                }
+                else {
+                    swiftWriter.emitStatement("return nil");
+                }
+            }
             swiftWriter.emitStatement("}");
         }