Enable more eslint rules

ark120202 · ark120202 · commit a702f4b53d55 · 2020-03-21T18:50:33.000Z
diff --git a/.eslintrc.js b/.eslintrc.js
@@ -112,6 +112,28 @@ module.exports = {
             { enforceForRenamedProperties: false },
         ],
         "prefer-numeric-literals": ["error"],
+        "no-lonely-if": ["error"],
+        "prefer-rest-params": ["error"],
+        "prefer-spread": ["error"],
+        "no-useless-computed-key": ["error"],
+        "for-direction": ["error"],
+        "no-compare-neg-zero": ["error"],
+        "no-dupe-else-if": ["error"],
+        "no-empty": ["error", { allowEmptyCatch: true }],
+        "no-implicit-coercion": ["error", { boolean: true, number: true, string: true }],
+        "operator-assignment": ["error"],
+        "no-path-concat": ["error"],
+        "no-compare-neg-zero": ["error"],
+        "no-control-regex": ["error"],
+        "no-unneeded-ternary": ["error", { defaultAssignment: false }],
+        "one-var": ["error", "never"],
+        "prefer-exponentiation-operator": ["error"],
+        "prefer-object-spread": ["error"],
+        "no-useless-call": ["off"],
+        "no-useless-catch": ["error"],
+        "no-useless-concat": ["error"],
+        "no-useless-escape": ["error"],
+        "no-useless-return": ["error"],
 
         "import/no-default-export": "error",
     },
diff --git a/src/LuaAST.ts b/src/LuaAST.ts
@@ -145,7 +145,7 @@ export function createNode(kind: SyntaxKind, tsOriginal?: ts.Node): Node {
 }
 
 export function cloneNode<T extends Node>(node: T): T {
-    return Object.assign({}, node);
+    return { ...node };
 }
 
 export function setNodePosition<T extends Node>(node: T, position: TextRange): T {
diff --git a/src/LuaPrinter.ts b/src/LuaPrinter.ts
@@ -31,7 +31,7 @@ export const escapeString = (value: string) => `"${value.replace(escapeStringReg
  * `foo.bar` => passes (`function foo.bar()` is valid)
  * `getFoo().bar` => fails (`function getFoo().bar()` would be illegal)
  */
-const isValidLuaFunctionDeclarationName = (str: string) => /^[a-zA-Z0-9_\.]+$/.test(str);
+const isValidLuaFunctionDeclarationName = (str: string) => /^[a-zA-Z0-9_.]+$/.test(str);
 
 /**
  * Returns true if expression contains no function calls.
@@ -217,7 +217,7 @@ export class LuaPrinter {
     }
 
     protected pushIndent(): void {
-        this.currentIndent = this.currentIndent + "    ";
+        this.currentIndent += "    ";
     }
 
     protected popIndent(): void {
diff --git a/src/lualib/ArrayFind.ts b/src/lualib/ArrayFind.ts
@@ -11,7 +11,7 @@ function __TS__ArrayFind<T>(
         if (predicate(elem, k, arr)) {
             return elem;
         }
-        k = k + 1;
+        k += 1;
     }
 
     return undefined;
diff --git a/src/lualib/ArrayReduceRight.ts b/src/lualib/ArrayReduceRight.ts
@@ -15,7 +15,7 @@ function __TS__ArrayReduceRight<T>(
         accumulator = select(1, ...initial);
     } else if (len > 0) {
         accumulator = arr[k];
-        k = k - 1;
+        k -= 1;
     } else {
         throw "Reduce of empty array with no initial value";
     }
diff --git a/src/lualib/ArrayReverse.ts b/src/lualib/ArrayReverse.ts
@@ -5,8 +5,8 @@ function __TS__ArrayReverse(this: void, arr: any[]): any[] {
         const temp = arr[j];
         arr[j] = arr[i];
         arr[i] = temp;
-        i = i + 1;
-        j = j - 1;
+        i += 1;
+        j -= 1;
     }
     return arr;
 }
diff --git a/src/lualib/InstanceOf.ts b/src/lualib/InstanceOf.ts
@@ -4,6 +4,7 @@ function __TS__InstanceOf(this: void, obj: LuaClassInstance, classTbl: LuaClass)
     }
 
     if (classTbl[Symbol.hasInstance] !== undefined) {
+        // eslint-disable-next-line no-implicit-coercion
         return !!classTbl[Symbol.hasInstance](obj);
     }
 
diff --git a/src/lualib/Iterator.ts b/src/lualib/Iterator.ts
@@ -12,7 +12,7 @@ function __TS__Iterator<T>(this: void, iterable: Iterable<T>): (this: void) => T
     } else {
         let i = 0;
         return () => {
-            i = i + 1;
+            i += 1;
             return iterable[i];
         };
     }
diff --git a/src/lualib/Map.ts b/src/lualib/Map.ts
@@ -42,7 +42,6 @@ Map = class Map<K, V> {
         this.firstKey = undefined;
         this.lastKey = undefined;
         this.size = 0;
-        return;
     }
 
     public delete(key: K): boolean {
@@ -79,7 +78,6 @@ Map = class Map<K, V> {
         for (const key of this.keys()) {
             callback(this.items.get(key), key, this);
         }
-        return;
     }
 
     public get(key: K): V | undefined {
diff --git a/src/lualib/Set.ts b/src/lualib/Set.ts
@@ -56,7 +56,6 @@ Set = class Set<T> {
         this.firstKey = undefined;
         this.lastKey = undefined;
         this.size = 0;
-        return;
     }
 
     public delete(value: T): boolean {
diff --git a/src/lualib/StringConcat.ts b/src/lualib/StringConcat.ts
@@ -1,7 +1,7 @@
 function __TS__StringConcat(this: void, str1: string, ...args: string[]): string {
     let out = str1;
     for (const arg of args) {
-        out = out + arg;
+        out += arg;
     }
     return out;
 }
diff --git a/src/lualib/StringPadEnd.ts b/src/lualib/StringPadEnd.ts
@@ -8,7 +8,7 @@ function __TS__StringPadEnd(this: string, maxLength: number, fillString = " "):
         return this;
     }
 
-    maxLength = maxLength - this.length;
+    maxLength -= this.length;
     if (maxLength > fillString.length) {
         fillString += fillString.repeat(maxLength / fillString.length);
     }
diff --git a/src/lualib/StringPadStart.ts b/src/lualib/StringPadStart.ts
@@ -8,7 +8,7 @@ function __TS__StringPadStart(this: string, maxLength: number, fillString = " ")
         return this;
     }
 
-    maxLength = maxLength - this.length;
+    maxLength -= this.length;
     if (maxLength > fillString.length) {
         fillString += fillString.repeat(maxLength / fillString.length);
     }
diff --git a/src/transformation/visitors/loops/for-of.ts b/src/transformation/visitors/loops/for-of.ts
@@ -88,6 +88,7 @@ function transformForOfLuaIteratorStatement(
             // Variables NOT declared in for loop - catch iterator values in temps and assign
             // for ____value0 in ${iterable} do
             //     ${initializer} = ____value0
+            // eslint-disable-next-line no-lonely-if
             if (ts.isArrayLiteralExpression(statement.initializer)) {
                 identifiers = statement.initializer.elements.map((_, i) => lua.createIdentifier(`____value${i}`));
                 if (identifiers.length > 0) {
diff --git a/test/legacy-utils.ts b/test/legacy-utils.ts
@@ -93,11 +93,11 @@ export function transpileAndExecute(
     luaHeader?: string,
     tsHeader?: string
 ): any {
-    const wrappedTsString = `${tsHeader ? tsHeader : ""}
+    const wrappedTsString = `${tsHeader ?? ""}
         declare function JSONStringify(this: void, p: any): string;
         function __runTest(this: void): any {${tsStr}}`;
 
-    const lua = `${luaHeader ? luaHeader : ""}
+    const lua = `${luaHeader ?? ""}
         ${transpileString(wrappedTsString, compilerOptions, false)}
         return __runTest();`;
 
@@ -162,7 +162,7 @@ export function transpileExecuteAndReturnExport(
         ${tsStr}`;
 
     const lua = `return (function()
-        ${luaHeader ? luaHeader : ""}
+        ${luaHeader ?? ""}
         ${transpileString(wrappedTsString, compilerOptions, false)}
         end)().${returnExport}`;
 
diff --git a/test/unit/loops.spec.ts b/test/unit/loops.spec.ts
@@ -197,8 +197,8 @@ test("for scope", () => {
 
 test.each([
     {
-        inp: { ["test1"]: 0, ["test2"]: 1, ["test3"]: 2 },
-        expected: { ["test1"]: 1, ["test2"]: 2, ["test3"]: 3 },
+        inp: { test1: 0, test2: 1, test3: 2 },
+        expected: { test1: 1, test2: 2, test3: 3 },
     },
 ])("forin[Object] (%p)", ({ inp, expected }) => {
     const result = util.transpileAndExecute(
diff --git a/test/util.ts b/test/util.ts
@@ -94,7 +94,7 @@ function transpileJs(program: ts.Program): TranspileJsResult {
         for (const sourceFile of sourceFiles) {
             const isJs = fileName.endsWith(".js");
             const isSourceMap = fileName.endsWith(".js.map");
-            if (isJs || isSourceMap) {
+            if (isJs) {
                 updateTranspiledFile(sourceFile.fileName, { js: data });
             } else if (isSourceMap) {
                 updateTranspiledFile(sourceFile.fileName, { sourceMap: data });

Original file line number	Diff line number	Diff line change
`@@ -145,7 +145,7 @@ export function createNode(kind: SyntaxKind, tsOriginal?: ts.Node): Node {`
`145`	`145`	`}`
`146`	`146`
`147`	`147`	`export function cloneNode<T extends Node>(node: T): T {`
`148`		`- return Object.assign({}, node);`
	`148`	`+ return { ...node };`
`149`	`149`	`}`
`150`	`150`
`151`	`151`	`export function setNodePosition<T extends Node>(node: T, position: TextRange): T {`
Original file line number	Diff line number	Diff line change
@@ -31,7 +31,7 @@ export const escapeString = (value: string) => `"${value.replace(escapeStringReg
`31`	`31`	* `foo.bar` => passes (`function foo.bar()` is valid)
`32`	`32`	* `getFoo().bar` => fails (`function getFoo().bar()` would be illegal)
`33`	`33`	`*/`
`34`		`-const isValidLuaFunctionDeclarationName = (str: string) => /^[a-zA-Z0-9_\.]+$/.test(str);`
	`34`	`+const isValidLuaFunctionDeclarationName = (str: string) => /^[a-zA-Z0-9_.]+$/.test(str);`
`35`	`35`
`36`	`36`	`/**`
`37`	`37`	`* Returns true if expression contains no function calls.`
`@@ -217,7 +217,7 @@ export class LuaPrinter {`
`217`	`217`	`}`
`218`	`218`
`219`	`219`	`protected pushIndent(): void {`
`220`		`- this.currentIndent = this.currentIndent + " ";`
	`220`	`+ this.currentIndent += " ";`
`221`	`221`	`}`
`222`	`222`
`223`	`223`	`protected popIndent(): void {`
Original file line number	Diff line number	Diff line change
`@@ -11,7 +11,7 @@ function __TS__ArrayFind<T>(`
`11`	`11`	`if (predicate(elem, k, arr)) {`
`12`	`12`	`return elem;`
`13`	`13`	`}`
`14`		`- k = k + 1;`
	`14`	`+ k += 1;`
`15`	`15`	`}`
`16`	`16`
`17`	`17`	`return undefined;`
Original file line number	Diff line number	Diff line change
`@@ -15,7 +15,7 @@ function __TS__ArrayReduceRight<T>(`
`15`	`15`	`accumulator = select(1, ...initial);`
`16`	`16`	`} else if (len > 0) {`
`17`	`17`	`accumulator = arr[k];`
`18`		`- k = k - 1;`
	`18`	`+ k -= 1;`
`19`	`19`	`} else {`
`20`	`20`	`throw "Reduce of empty array with no initial value";`
`21`	`21`	`}`
Original file line number	Diff line number	Diff line change
`@@ -5,8 +5,8 @@ function __TS__ArrayReverse(this: void, arr: any[]): any[] {`
`5`	`5`	`const temp = arr[j];`
`6`	`6`	`arr[j] = arr[i];`
`7`	`7`	`arr[i] = temp;`
`8`		`- i = i + 1;`
`9`		`- j = j - 1;`
	`8`	`+ i += 1;`
	`9`	`+ j -= 1;`
`10`	`10`	`}`
`11`	`11`	`return arr;`
`12`	`12`	`}`
Original file line number	Diff line number	Diff line change
`@@ -4,6 +4,7 @@ function __TS__InstanceOf(this: void, obj: LuaClassInstance, classTbl: LuaClass)`
`4`	`4`	`}`
`5`	`5`
`6`	`6`	`if (classTbl[Symbol.hasInstance] !== undefined) {`
	`7`	`+ // eslint-disable-next-line no-implicit-coercion`
`7`	`8`	`return !!classTbl[Symbol.hasInstance](obj);`
`8`	`9`	`}`
`9`	`10`
Original file line number	Diff line number	Diff line change
`@@ -12,7 +12,7 @@ function __TS__Iterator<T>(this: void, iterable: Iterable<T>): (this: void) => T`
`12`	`12`	`} else {`
`13`	`13`	`let i = 0;`
`14`	`14`	`return () => {`
`15`		`- i = i + 1;`
	`15`	`+ i += 1;`
`16`	`16`	`return iterable[i];`
`17`	`17`	`};`
`18`	`18`	`}`
Original file line number	Diff line number	Diff line change
`@@ -42,7 +42,6 @@ Map = class Map<K, V> {`
`42`	`42`	`this.firstKey = undefined;`
`43`	`43`	`this.lastKey = undefined;`
`44`	`44`	`this.size = 0;`
`45`		`- return;`
`46`	`45`	`}`
`47`	`46`
`48`	`47`	`public delete(key: K): boolean {`
`@@ -79,7 +78,6 @@ Map = class Map<K, V> {`
`79`	`78`	`for (const key of this.keys()) {`
`80`	`79`	`callback(this.items.get(key), key, this);`
`81`	`80`	`}`
`82`		`- return;`
`83`	`81`	`}`
`84`	`82`
`85`	`83`	`public get(key: K): V \| undefined {`
Original file line number	Diff line number	Diff line change
`@@ -56,7 +56,6 @@ Set = class Set<T> {`
`56`	`56`	`this.firstKey = undefined;`
`57`	`57`	`this.lastKey = undefined;`
`58`	`58`	`this.size = 0;`
`59`		`- return;`
`60`	`59`	`}`
`61`	`60`
`62`	`61`	`public delete(value: T): boolean {`