Fixed and improved lualib ternary conditional

Perryvw · Perryvw · commit deaf45548ba5 · 2018-07-20T12:18:32.000+02:00
diff --git a/src/Transpiler.ts b/src/Transpiler.ts
@@ -874,7 +874,7 @@ export abstract class LuaTranspiler {
         const val2 = this.transpileExpression(node.whenFalse);
 
         return this.transpileLuaLibFunction(LuaLibFeature.Ternary, condition,
-                                            `function() return ${val1} end`, `function() return ${val2} end)`);
+                                            `function() return ${val1} end`, `function() return ${val2} end`);
     }
 
     public transpilePostfixUnaryExpression(node: ts.PostfixUnaryExpression): string {
diff --git a/src/lualib/Ternary.ts b/src/lualib/Ternary.ts
@@ -1,7 +1,7 @@
-function __TS__Ternary(condition: any, cb1: () => void, cb2: () => void) {
+function __TS__Ternary<T>(condition: boolean, cb1: () => T, cb2: () => T): T {
     if (condition) {
-        cb1();
+        return cb1();
     } else {
-        cb2();
+        return cb2();
     }
 }
diff --git a/test/unit/expressions.spec.ts b/test/unit/expressions.spec.ts
@@ -181,13 +181,6 @@ export class ExpressionTests {
         Expect(util.transpileString(input)).toBe(lua);
     }
 
-    @TestCase("1 + a ? 3*a : c", "TS_ITE(1+a,function() return 3*a end,function() return c end)")
-    @TestCase("a ? b : c", "TS_ITE(a,function() return b end,function() return c end)")
-    @Test("Ternary operator")
-    public conditional(input: string, lua: string) {
-        Expect(util.transpileString(input)).toBe(lua);
-    }
-
     @Test("Null Expression")
     public nullExpression() {
         Expect(util.transpileString("null")).toBe("nil");
diff --git a/test/unit/lualib.spec.ts b/test/unit/lualib.spec.ts
@@ -1,6 +1,7 @@
-import { Expect, Test, TestCase } from "alsatian";
+import { Expect, Test, TestCase, FocusTests } from "alsatian";
 import * as util from "../src/util";
 
+@FocusTests
 export class LuaLibArrayTests {
 
     @TestCase([0, 1, 2, 3], [1, 2, 3, 4])
@@ -261,4 +262,39 @@ export class LuaLibArrayTests {
         // Assert
         Expect(result).toBe(JSON.stringify([0].concat(inp)));
     }
+
+    @TestCase("true", "4", "5", 4)
+    @TestCase("false", "4", "5", 5)
+    @TestCase("3", "4", "5", 4)
+    @Test("Ternary Conditional")
+    public ternaryConditional(condition: string, lhs: string, rhs: string, expected: any) {
+        // Transpile
+        const lua = util.transpileString(`return ${condition} ? ${lhs} : ${rhs};`);
+
+        // Execute
+        const result = util.executeLua(lua);
+
+        // Assert
+        Expect(result).toBe(expected);
+    }
+
+    @TestCase("true", 11)
+    @TestCase("false", 13)
+    @TestCase("a < 4", 13)
+    @TestCase("a == 8", 11)
+    @Test("Ternary Conditional Delayed")
+    public ternaryConditionalDelayed(condition: string, expected: any) {
+        // Transpile
+        const lua = util.transpileString(
+            `let a = 3;
+             let delay = () => ${condition} ? a + 3 : a + 5;
+             a = 8;
+             return delay();`);
+
+        // Execute
+        const result = util.executeLua(lua);
+
+        // Assert
+        Expect(result).toBe(expected);
+    }
 }

Original file line number	Diff line number	Diff line change
`@@ -874,7 +874,7 @@ export abstract class LuaTranspiler {`
`874`	`874`	`const val2 = this.transpileExpression(node.whenFalse);`
`875`	`875`
`876`	`876`	`return this.transpileLuaLibFunction(LuaLibFeature.Ternary, condition,`
`877`		- `function() return ${val1} end`, `function() return ${val2} end)`);
	`877`	+ `function() return ${val1} end`, `function() return ${val2} end`);
`878`	`878`	`}`
`879`	`879`
`880`	`880`	`public transpilePostfixUnaryExpression(node: ts.PostfixUnaryExpression): string {`
Original file line number	Diff line number	Diff line change
`@@ -1,7 +1,7 @@`
`1`		`-function __TS__Ternary(condition: any, cb1: () => void, cb2: () => void) {`
	`1`	`+function __TS__Ternary<T>(condition: boolean, cb1: () => T, cb2: () => T): T {`
`2`	`2`	`if (condition) {`
`3`		`- cb1();`
	`3`	`+ return cb1();`
`4`	`4`	`} else {`
`5`		`- cb2();`
	`5`	`+ return cb2();`
`6`	`6`	`}`
`7`	`7`	`}`