TypeScriptToLua · Perryvw · May 24, 2020 · May 16, 2020 · May 19, 2020 · May 19, 2020
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+- Added new `"luaTarget"` option value - `"universal"`. Choosing this target would make TypeScriptToLua generate code compatible with all supported Lua targets.
+  - **BREAKING CHANGE:** This is a new default target. If you have been depending on LuaJIT being chosen implicitly, now you have to enable it explicitly with `"luaTarget": "JIT"` in the `tsconfig.json` file.
+
 <!-- TODO: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-9.html doesn't seem to work now -->
 
 - TypeScript has been updated to 3.9. See [release notes](https://devblogs.microsoft.com/typescript/announcing-typescript-3-9/) for details. This update includes some fixes specific to our API usage:

diff --git a/src/CompilerOptions.ts b/src/CompilerOptions.ts
@@ -44,6 +44,7 @@ export enum LuaLibImportKind {
 }
 
 export enum LuaTarget {
+    Universal = "universal",
     Lua51 = "5.1",
     Lua52 = "5.2",
     Lua53 = "5.3",

diff --git a/src/LuaLib.ts b/src/LuaLib.ts
@@ -38,6 +38,7 @@ export enum LuaLibFeature {
     InstanceOfObject = "InstanceOfObject",
     Iterator = "Iterator",
     Map = "Map",
+    MathAtan2 = "MathAtan2",
     New = "New",
     Number = "Number",
     NumberIsFinite = "NumberIsFinite",
@@ -67,12 +68,16 @@ export enum LuaLibFeature {
     Symbol = "Symbol",
     SymbolRegistry = "SymbolRegistry",
     TypeOf = "TypeOf",
+    Unpack = "Unpack",
 }
 
 const luaLibDependencies: Partial<Record<LuaLibFeature, LuaLibFeature[]>> = {
     ArrayFlat: [LuaLibFeature.ArrayConcat],
     ArrayFlatMap: [LuaLibFeature.ArrayConcat],
     Error: [LuaLibFeature.New, LuaLibFeature.Class, LuaLibFeature.FunctionCall],
+    FunctionApply: [LuaLibFeature.Unpack],
+    FunctionBind: [LuaLibFeature.Unpack],
+    FunctionCall: [LuaLibFeature.Unpack],
     Generator: [LuaLibFeature.Symbol],
     InstanceOf: [LuaLibFeature.Symbol],
     Iterator: [LuaLibFeature.Symbol],
@@ -81,7 +86,7 @@ const luaLibDependencies: Partial<Record<LuaLibFeature, LuaLibFeature[]>> = {
     Set: [LuaLibFeature.InstanceOf, LuaLibFeature.Iterator, LuaLibFeature.Symbol],
     WeakMap: [LuaLibFeature.InstanceOf, LuaLibFeature.Iterator, LuaLibFeature.Symbol],
     WeakSet: [LuaLibFeature.InstanceOf, LuaLibFeature.Iterator, LuaLibFeature.Symbol],
-    Spread: [LuaLibFeature.Iterator],
+    Spread: [LuaLibFeature.Iterator, LuaLibFeature.Unpack],
     SymbolRegistry: [LuaLibFeature.Symbol],
 };
 

diff --git a/src/lualib/FunctionApply.ts b/src/lualib/FunctionApply.ts
@@ -1,6 +1,6 @@
 function __TS__FunctionApply(this: void, fn: (this: void, ...args: any[]) => any, thisArg: any, args?: any[]): any {
     if (args) {
-        return fn(thisArg, (unpack || table.unpack)(args));
+        return fn(thisArg, ...args);
     } else {
         return fn(thisArg);
     }

diff --git a/src/lualib/FunctionBind.ts b/src/lualib/FunctionBind.ts
@@ -8,6 +8,6 @@ function __TS__FunctionBind(
         for (let i = 0; i < boundArgs.length; ++i) {
             table.insert(args, i + 1, boundArgs[i]);
         }
-        return fn(thisArg, (unpack || table.unpack)(args));
+        return fn(thisArg, ...args);
     };
 }
diff --git a/src/lualib/FunctionCall.ts b/src/lualib/FunctionCall.ts
@@ -1,3 +1,3 @@
 function __TS__FunctionCall(this: void, fn: (this: void, ...args: any[]) => any, thisArg: any, ...args: any[]): any {
-    return fn(thisArg, (unpack || table.unpack)(args));
+    return fn(thisArg, ...args);
 }
diff --git a/src/lualib/MathAtan2.ts b/src/lualib/MathAtan2.ts
@@ -0,0 +1 @@
+const __TS__MathAtan2 = math.atan2 || math.atan;
diff --git a/src/lualib/Spread.ts b/src/lualib/Spread.ts
@@ -10,5 +10,5 @@ function __TS__Spread<T>(this: void, iterable: string | Iterable<T>): T[] {
             arr[arr.length] = item;
         }
     }
-    return (table.unpack || unpack)(arr);
+    return __TS__Unpack(arr);
 }
diff --git a/src/lualib/Unpack.ts b/src/lualib/Unpack.ts
@@ -0,0 +1 @@
+const __TS__Unpack = table.unpack || unpack;
diff --git a/src/lualib/declarations/math.d.ts b/src/lualib/declarations/math.d.ts
@@ -2,4 +2,10 @@
 declare namespace math {
     /** @tupleReturn */
     function modf(x: number): [number, number];
+
+    function atan(x: number): number;
+    // eslint-disable-next-line @typescript-eslint/unified-signatures
+    function atan(y: number, x?: number): number;
+
+    function atan2(y: number, x: number): number;
 }
diff --git a/src/lualib/tsconfig.json b/src/lualib/tsconfig.json
@@ -11,7 +11,6 @@
     },
     "tstl": {
         "luaLibImport": "none",
-        "luaTarget": "5.1",
         "noHeader": true
     }
 }
diff --git a/src/transformation/builtins/math.ts b/src/transformation/builtins/math.ts
@@ -1,8 +1,9 @@
 import * as ts from "typescript";
-import * as lua from "../../LuaAST";
 import { LuaTarget } from "../../CompilerOptions";
+import * as lua from "../../LuaAST";
 import { TransformationContext } from "../context";
 import { unsupportedProperty } from "../utils/diagnostics";
+import { LuaLibFeature, transformLuaLibFunction } from "../utils/lualib";
 import { PropertyCallExpression, transformArguments } from "../visitors/call";
 
 export function transformMathProperty(
@@ -37,22 +38,24 @@ export function transformMathCall(
     const expression = node.expression;
     const signature = context.checker.getResolvedSignature(node);
     const params = transformArguments(context, node.arguments, signature);
+    const math = lua.createIdentifier("math");
 
     const expressionName = expression.name.text;
     switch (expressionName) {
         // Lua 5.3: math.atan(y, x)
         // Otherwise: math.atan2(y, x)
         case "atan2": {
-            const math = lua.createIdentifier("math");
-            const methodName = context.options.luaTarget === LuaTarget.Lua53 ? "atan" : expressionName;
-            const method = lua.createStringLiteral(methodName);
+            if (context.luaTarget === LuaTarget.Universal) {
+                return transformLuaLibFunction(context, LuaLibFeature.MathAtan2, node, ...params);
+            }
+
+            const method = lua.createStringLiteral(context.luaTarget === LuaTarget.Lua53 ? "atan" : "atan2");
             return lua.createCallExpression(lua.createTableIndexExpression(math, method), params, node);
         }
 
         // (math.log(x) / Math.LNe)
         case "log10":
         case "log2": {
-            const math = lua.createIdentifier("math");
             const log1 = lua.createTableIndexExpression(math, lua.createStringLiteral("log"));
             const logCall1 = lua.createCallExpression(log1, params);
             const e = lua.createNumericLiteral(expressionName === "log10" ? Math.LN10 : Math.LN2);
@@ -61,7 +64,6 @@ export function transformMathCall(
 
         // math.log(1 + x)
         case "log1p": {
-            const math = lua.createIdentifier("math");
             const log = lua.createStringLiteral("log");
             const one = lua.createNumericLiteral(1);
             const add = lua.createBinaryExpression(one, params[0], lua.SyntaxKind.AdditionOperator);
@@ -70,7 +72,6 @@ export function transformMathCall(
 
         // math.floor(x + 0.5)
         case "round": {
-            const math = lua.createIdentifier("math");
             const floor = lua.createStringLiteral("floor");
             const half = lua.createNumericLiteral(0.5);
             const add = lua.createBinaryExpression(params[0], half, lua.SyntaxKind.AdditionOperator);
@@ -93,7 +94,6 @@ export function transformMathCall(
         case "sin":
         case "sqrt":
         case "tan": {
-            const math = lua.createIdentifier("math");
             const method = lua.createStringLiteral(expressionName);
             return lua.createCallExpression(lua.createTableIndexExpression(math, method), params, node);
         }

diff --git a/src/transformation/context/context.ts b/src/transformation/context/context.ts
@@ -32,7 +32,7 @@ export class TransformationContext {
     public readonly resolver: EmitResolver;
 
     public readonly options: CompilerOptions = this.program.getCompilerOptions();
-    public readonly luaTarget = this.options.luaTarget ?? LuaTarget.LuaJIT;
+    public readonly luaTarget = this.options.luaTarget ?? LuaTarget.Universal;
     public readonly isModule = ts.isExternalModule(this.sourceFile);
     public readonly isStrict =
         (this.options.alwaysStrict ?? this.options.strict) ||

diff --git a/src/transformation/utils/diagnostics.ts b/src/transformation/utils/diagnostics.ts
@@ -107,7 +107,7 @@ export const unsupportedRightShiftOperator = createDiagnosticFactory(
 
 const getLuaTargetName = (version: LuaTarget) => (version === LuaTarget.LuaJIT ? "LuaJIT" : `Lua ${version}`);
 export const unsupportedForTarget = createDiagnosticFactory(
-    (functionality: string, version: LuaTarget) =>
+    (functionality: string, version: Exclude<LuaTarget, LuaTarget.Universal>) =>
         `${functionality} is/are not supported for target ${getLuaTargetName(version)}.`
 );
 

diff --git a/src/transformation/utils/lua-ast.ts b/src/transformation/utils/lua-ast.ts
@@ -6,6 +6,8 @@ import { TransformationContext } from "../context";
 import { createExportedIdentifier, getIdentifierExportScope } from "./export";
 import { peekScope, ScopeType } from "./scope";
 import { isFunctionType } from "./typescript";
+import { transformLuaLibFunction } from "./lualib";
+import { LuaLibFeature } from "../../LuaLib";
 
 export type OneToManyVisitorResult<T extends lua.Node> = T | T[] | undefined;
 export function unwrapVisitorResult<T extends lua.Node>(result: OneToManyVisitorResult<T>): T[] {
@@ -56,6 +58,10 @@ export function createUnpackCall(
     expression: lua.Expression,
     tsOriginal?: ts.Node
 ): lua.Expression {
+    if (context.luaTarget === LuaTarget.Universal) {
+        return transformLuaLibFunction(context, LuaLibFeature.Unpack, tsOriginal, expression);
+    }
+
     const unpack =
         context.luaTarget === LuaTarget.Lua51 || context.luaTarget === LuaTarget.LuaJIT
             ? lua.createIdentifier("unpack")

diff --git a/src/transformation/visitors/binary-expression/bit.ts b/src/transformation/visitors/binary-expression/bit.ts
@@ -62,6 +62,7 @@ export function transformBinaryBitOperation(
     operator: BitOperator
 ): lua.Expression {
     switch (context.luaTarget) {
+        case LuaTarget.Universal:
         case LuaTarget.Lua51:
             context.diagnostics.push(unsupportedForTarget(node, "Bitwise operations", LuaTarget.Lua51));
 
@@ -105,6 +106,7 @@ export function transformUnaryBitOperation(
     operator: lua.UnaryBitwiseOperator
 ): lua.Expression {
     switch (context.luaTarget) {
+        case LuaTarget.Universal:
         case LuaTarget.Lua51:
             context.diagnostics.push(unsupportedForTarget(node, "Bitwise operations", LuaTarget.Lua51));
 

diff --git a/src/transformation/visitors/break-continue.ts b/src/transformation/visitors/break-continue.ts
@@ -15,7 +15,7 @@ export const transformBreakStatement: FunctionVisitor<ts.BreakStatement> = (brea
 };
 
 export const transformContinueStatement: FunctionVisitor<ts.ContinueStatement> = (statement, context) => {
-    if (context.luaTarget === LuaTarget.Lua51) {
+    if (context.luaTarget === LuaTarget.Universal || context.luaTarget === LuaTarget.Lua51) {
         context.diagnostics.push(unsupportedForTarget(statement, "Continue statement", LuaTarget.Lua51));
     }
 

diff --git a/src/transformation/visitors/switch.ts b/src/transformation/visitors/switch.ts
@@ -6,7 +6,7 @@ import { unsupportedForTarget } from "../utils/diagnostics";
 import { performHoisting, popScope, pushScope, ScopeType } from "../utils/scope";
 
 export const transformSwitchStatement: FunctionVisitor<ts.SwitchStatement> = (statement, context) => {
-    if (context.luaTarget === LuaTarget.Lua51) {
+    if (context.luaTarget === LuaTarget.Universal || context.luaTarget === LuaTarget.Lua51) {
         context.diagnostics.push(unsupportedForTarget(statement, "Switch statements", LuaTarget.Lua51));
     }
 

diff --git a/test/cli/parse.spec.ts b/test/cli/parse.spec.ts
@@ -110,6 +110,7 @@ describe("command line", () => {
             ["luaLibImport", "inline", { luaLibImport: tstl.LuaLibImportKind.Inline }],
             ["luaLibImport", "require", { luaLibImport: tstl.LuaLibImportKind.Require }],
 
+            ["luaTarget", "universal", { luaTarget: tstl.LuaTarget.Universal }],
             ["luaTarget", "5.1", { luaTarget: tstl.LuaTarget.Lua51 }],
             ["luaTarget", "5.2", { luaTarget: tstl.LuaTarget.Lua52 }],
             ["luaTarget", "5.3", { luaTarget: tstl.LuaTarget.Lua53 }],
@@ -216,6 +217,7 @@ describe("tsconfig", () => {
             ["luaLibImport", "inline", { luaLibImport: tstl.LuaLibImportKind.Inline }],
             ["luaLibImport", "require", { luaLibImport: tstl.LuaLibImportKind.Require }],
 
+            ["luaTarget", "universal", { luaTarget: tstl.LuaTarget.Universal }],
             ["luaTarget", "5.1", { luaTarget: tstl.LuaTarget.Lua51 }],
             ["luaTarget", "5.2", { luaTarget: tstl.LuaTarget.Lua52 }],
             ["luaTarget", "5.3", { luaTarget: tstl.LuaTarget.Lua53 }],

diff --git a/test/unit/__snapshots__/loops.spec.ts.snap b/test/unit/__snapshots__/loops.spec.ts.snap
@@ -25,6 +25,19 @@ until not false"
 
 exports[`loop continue (do { continue; } while (false)) [5.1]: diagnostics 1`] = `"main.ts(1,6): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
 
+exports[`loop continue (do { continue; } while (false)) [universal]: code 1`] = `
+"repeat
+    do
+        do
+            goto __continue2
+        end
+        ::__continue2::
+    end
+until not false"
+`;
+
+exports[`loop continue (do { continue; } while (false)) [universal]: diagnostics 1`] = `"main.ts(1,6): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
+
 exports[`loop continue (for (;;) { continue; }) [5.1]: code 1`] = `
 "do
     while true do
@@ -38,6 +51,19 @@ end"
 
 exports[`loop continue (for (;;) { continue; }) [5.1]: diagnostics 1`] = `"main.ts(1,12): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
 
+exports[`loop continue (for (;;) { continue; }) [universal]: code 1`] = `
+"do
+    while true do
+        do
+            goto __continue2
+        end
+        ::__continue2::
+    end
+end"
+`;
+
+exports[`loop continue (for (;;) { continue; }) [universal]: diagnostics 1`] = `"main.ts(1,12): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
+
 exports[`loop continue (for (const a in {}) { continue; }) [5.1]: code 1`] = `
 "for a in pairs({}) do
     do
@@ -49,6 +75,17 @@ end"
 
 exports[`loop continue (for (const a in {}) { continue; }) [5.1]: diagnostics 1`] = `"main.ts(1,23): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
 
+exports[`loop continue (for (const a in {}) { continue; }) [universal]: code 1`] = `
+"for a in pairs({}) do
+    do
+        goto __continue2
+    end
+    ::__continue2::
+end"
+`;
+
+exports[`loop continue (for (const a in {}) { continue; }) [universal]: diagnostics 1`] = `"main.ts(1,23): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
+
 exports[`loop continue (for (const a of []) { continue; }) [5.1]: code 1`] = `
 "for ____, a in ipairs({}) do
     do
@@ -60,6 +97,17 @@ end"
 
 exports[`loop continue (for (const a of []) { continue; }) [5.1]: diagnostics 1`] = `"main.ts(1,23): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
 
+exports[`loop continue (for (const a of []) { continue; }) [universal]: code 1`] = `
+"for ____, a in ipairs({}) do
+    do
+        goto __continue2
+    end
+    ::__continue2::
+end"
+`;
+
+exports[`loop continue (for (const a of []) { continue; }) [universal]: diagnostics 1`] = `"main.ts(1,23): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
+
 exports[`loop continue (while (false) { continue; }) [5.1]: code 1`] = `
 "while false do
     do
@@ -70,3 +118,14 @@ end"
 `;
 
 exports[`loop continue (while (false) { continue; }) [5.1]: diagnostics 1`] = `"main.ts(1,17): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
+
+exports[`loop continue (while (false) { continue; }) [universal]: code 1`] = `
+"while false do
+    do
+        goto __continue2
+    end
+    ::__continue2::
+end"
+`;
+
+exports[`loop continue (while (false) { continue; }) [universal]: diagnostics 1`] = `"main.ts(1,17): error TSTL: Continue statement is/are not supported for target Lua 5.1."`;
diff --git a/test/unit/builtins/math.spec.ts b/test/unit/builtins/math.spec.ts
@@ -27,8 +27,11 @@ test.each(["E", "LN10", "LN2", "LOG10E", "LOG2E", "SQRT1_2", "SQRT2"])("Math.%s"
 
 const expectMathAtan2: util.TapCallback = builder => expect(builder.getMainLuaCodeChunk()).toContain("math.atan2(");
 const expectMathAtan: util.TapCallback = builder => expect(builder.getMainLuaCodeChunk()).toContain("math.atan(");
+const expectLualibMathAtan2: util.TapCallback = builder =>
+    expect(builder.getMainLuaCodeChunk()).toContain("__TS__MathAtan2(");
 
 util.testEachVersion("Math.atan2", () => util.testExpression`Math.atan2(4, 5)`, {
+    [tstl.LuaTarget.Universal]: builder => builder.tap(expectLualibMathAtan2),
     [tstl.LuaTarget.LuaJIT]: builder => builder.tap(expectMathAtan2),
     [tstl.LuaTarget.Lua51]: builder => builder.tap(expectMathAtan2),
     [tstl.LuaTarget.Lua52]: builder => builder.tap(expectMathAtan2),

diff --git a/test/unit/loops.spec.ts b/test/unit/loops.spec.ts
@@ -530,6 +530,7 @@ for (const testCase of [
         expect(builder.getMainLuaCodeChunk()).toMatch("::__continue2::");
 
     util.testEachVersion(`loop continue (${testCase})`, () => util.testModule(testCase), {
+        [tstl.LuaTarget.Universal]: builder => builder.expectDiagnosticsToMatchSnapshot([unsupportedForTarget.code]),
         [tstl.LuaTarget.Lua51]: builder => builder.expectDiagnosticsToMatchSnapshot([unsupportedForTarget.code]),
         [tstl.LuaTarget.Lua52]: expectContinueGotoLabel,
         [tstl.LuaTarget.Lua53]: expectContinueGotoLabel,

diff --git a/test/unit/spread.spec.ts b/test/unit/spread.spec.ts
@@ -5,6 +5,7 @@ import { formatCode } from "../util";
 // TODO: Make some utils for testing other targets
 const expectUnpack: util.TapCallback = builder => expect(builder.getMainLuaCodeChunk()).toMatch(/[^.]unpack\(/);
 const expectTableUnpack: util.TapCallback = builder => expect(builder.getMainLuaCodeChunk()).toContain("table.unpack");
+const expectLualibUnpack: util.TapCallback = builder => expect(builder.getMainLuaCodeChunk()).toContain("__TS__Unpack");
 
 const arrayLiteralCases = [
     "1, 2, ...[3, 4, 5]",
@@ -72,6 +73,7 @@ describe("in function call", () => {
             return foo(...array);
         `,
         {
+            [tstl.LuaTarget.Universal]: builder => builder.tap(expectLualibUnpack),
             [tstl.LuaTarget.LuaJIT]: builder => builder.tap(expectUnpack),
             [tstl.LuaTarget.Lua51]: builder => builder.tap(expectUnpack),
             [tstl.LuaTarget.Lua52]: builder => builder.tap(expectTableUnpack),
@@ -82,6 +84,7 @@ describe("in function call", () => {
 
 describe("in array literal", () => {
     util.testEachVersion(undefined, () => util.testExpression`[...[0, 1, 2]]`, {
+        [tstl.LuaTarget.Universal]: builder => builder.tap(expectLualibUnpack),
         [tstl.LuaTarget.LuaJIT]: builder => builder.tap(expectUnpack),
         [tstl.LuaTarget.Lua51]: builder => builder.tap(expectUnpack),
         [tstl.LuaTarget.Lua52]: builder => builder.tap(expectTableUnpack),
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		const __TS__MathAtan2 = math.atan2 \|\| math.atan;