fixed vararg optimization logic (#1046)

tomblind · web-flow · commit f034d9f322a3 · 2021-07-16T20:50:03.000+02:00
diff --git a/src/transformation/utils/scope.ts b/src/transformation/utils/scope.ts
@@ -92,9 +92,9 @@ export function popScope(context: TransformationContext): Scope {
     return scope;
 }
 
-function isDeclaredInScope(symbol: ts.Symbol, scopeNode: ts.Node) {
+function isHoistableFunctionDeclaredInScope(symbol: ts.Symbol, scopeNode: ts.Node) {
     return symbol?.declarations?.some(
-        d => findFirstNodeAbove(d, (n): n is ts.Node => n === scopeNode) && !ts.isParameter(d.parent)
+        d => ts.isFunctionDeclaration(d) && findFirstNodeAbove(d, (n): n is ts.Node => n === scopeNode)
     );
 }
 
@@ -109,7 +109,7 @@ export function hasReferencedUndefinedLocalFunction(context: TransformationConte
         if (
             !scope.functionDefinitions?.has(symbolId) &&
             type.getCallSignatures().length > 0 &&
-            isDeclaredInScope(type.symbol, scope.node)
+            isHoistableFunctionDeclaredInScope(type.symbol, scope.node)
         ) {
             return true;
         }
diff --git a/test/unit/__snapshots__/spread.spec.ts.snap b/test/unit/__snapshots__/spread.spec.ts.snap
@@ -81,6 +81,24 @@ end
 return ____exports"
 `;
 
+exports[`vararg spread optimization curry with indirect type 1`] = `
+"local ____exports = {}
+function ____exports.__main(self)
+    local function test(self, obj, ...)
+        local fn = obj.fn
+        return fn(nil, ...)
+    end
+    return test(
+        nil,
+        {
+            fn = function(____, arg) return arg end
+        },
+        \\"foobar\\"
+    )
+end
+return ____exports"
+`;
+
 exports[`vararg spread optimization finally clause 1`] = `
 "local ____exports = {}
 function ____exports.__main(self)
@@ -105,6 +123,21 @@ end
 return ____exports"
 `;
 
+exports[`vararg spread optimization function type declared inside scope 1`] = `
+"local ____exports = {}
+function ____exports.__main(self)
+    local function test(self, ...)
+        local function fn(____, ...)
+            local args = {...}
+            return args[1]
+        end
+        return fn(nil, ...)
+    end
+    test(nil, \\"foobar\\")
+end
+return ____exports"
+`;
+
 exports[`vararg spread optimization if statement 1`] = `
 "local ____exports = {}
 function ____exports.__main(self)
diff --git a/test/unit/spread.spec.ts b/test/unit/spread.spec.ts
@@ -241,6 +241,30 @@ describe("vararg spread optimization", () => {
             .expectLuaToMatchSnapshot()
             .expectToMatchJsResult();
     });
+
+    test("curry with indirect type", () => {
+        util.testFunction`
+            function test<A extends any[]>(obj: {fn: (...args: A) => void}, ...args: A) {
+                const fn = obj.fn;
+                return fn(...args);
+            }
+            return test({fn: (arg: string) => arg}, "foobar");
+        `
+            .expectLuaToMatchSnapshot()
+            .expectToMatchJsResult();
+    });
+
+    test("function type declared inside scope", () => {
+        util.testFunction`
+            function test<A extends any[]>(...args: A) {
+                const fn: (...args: A) => A[0] = (...args) => args[0];
+                return fn(...args);
+            }
+            test("foobar");
+        `
+            .expectLuaToMatchSnapshot()
+            .expectToMatchJsResult();
+    });
 });
 
 describe("vararg spread de-optimization", () => {

Original file line number	Diff line number	Diff line change
`@@ -92,9 +92,9 @@ export function popScope(context: TransformationContext): Scope {`
`92`	`92`	`return scope;`
`93`	`93`	`}`
`94`	`94`
`95`		`-function isDeclaredInScope(symbol: ts.Symbol, scopeNode: ts.Node) {`
	`95`	`+function isHoistableFunctionDeclaredInScope(symbol: ts.Symbol, scopeNode: ts.Node) {`
`96`	`96`	`return symbol?.declarations?.some(`
`97`		`- d => findFirstNodeAbove(d, (n): n is ts.Node => n === scopeNode) && !ts.isParameter(d.parent)`
	`97`	`+ d => ts.isFunctionDeclaration(d) && findFirstNodeAbove(d, (n): n is ts.Node => n === scopeNode)`
`98`	`98`	`);`
`99`	`99`	`}`
`100`	`100`
`@@ -109,7 +109,7 @@ export function hasReferencedUndefinedLocalFunction(context: TransformationConte`
`109`	`109`	`if (`
`110`	`110`	`!scope.functionDefinitions?.has(symbolId) &&`
`111`	`111`	`type.getCallSignatures().length > 0 &&`
`112`		`- isDeclaredInScope(type.symbol, scope.node)`
	`112`	`+ isHoistableFunctionDeclaredInScope(type.symbol, scope.node)`
`113`	`113`	`) {`
`114`	`114`	`return true;`
`115`	`115`	`}`