fix space-before-function-paren (#293)

* fix `space-before-function-paren`

* chmod +x bin/tslint-to-eslint-config

Author: bouzuya

bin/tslint-to-eslint-config

@@ -1,29 +1,38 @@
 import { RuleConverter } from "../converter";
 
-const NOT_SUPPORTED_OPTIONS = ["constructor", "method"];
+const SUPPORTED_OPTIONS: string[] = ["anonymous", "asyncArrow", "named"];
 
-function isExistedESLintOption(rule: string) {
-    return !NOT_SUPPORTED_OPTIONS.includes(rule);
-}
+type ObjectArgument = Record<string, "always" | "never">;
 
-export const convertSpaceBeforeFunctionParen: RuleConverter = tslintRule => {
-    const ruleArguments = tslintRule.ruleArguments.filter(isExistedESLintOption);
-    const notices = NOT_SUPPORTED_OPTIONS.reduce<string[]>((acc, option) => {
-        if (tslintRule.ruleArguments.includes(option)) {
-            acc.push(`Option "${option}" is not supported by ESLint.`);
-        }
-        return acc;
-    }, []);
+const isObjectArgument = (argument: unknown): argument is ObjectArgument =>
+    typeof argument === "object" && argument !== null;
 
-    return {
-        rules: [
-            {
-                ...(tslintRule.ruleArguments.length !== 0 && {
-                    ruleArguments,
+export const convertSpaceBeforeFunctionParen: RuleConverter = tslintRule => {
+    const argument: unknown = tslintRule.ruleArguments[0];
+    const ruleName = "space-before-function-paren";
+    if (argument === "always" || argument === "never") {
+        return { rules: [{ ruleArguments: [argument], ruleName }] };
+    }
+    if (isObjectArgument(argument)) {
+        const notices = Object.keys(argument)
+            .filter(option => !SUPPORTED_OPTIONS.includes(option))
+            .map(option => `Option "${option}" is not supported by ESLint.`);
+        const filtered = Object.keys(argument)
+            .filter(option => SUPPORTED_OPTIONS.includes(option))
+            .reduce<ObjectArgument>((obj, option) => {
+                return { ...obj, [option]: argument[option] };
+            }, {});
+        return {
+            rules: [
+                {
                     ...(notices.length !== 0 && { notices }),
-                }),
-                ruleName: "space-before-function-paren",
-            },
-        ],
-    };
+                    ...(Object.keys(filtered).length !== 0 && {
+                        ruleArguments: [filtered],
+                    }),
+                    ruleName,
+                },
+            ],
+        };
+    }
+    return { rules: [{ ruleName }] };
 };

src/rules/converters/space-before-function-paren.ts

@@ -15,15 +15,45 @@ describe(convertSpaceBeforeFunctionParen, () => {
         });
     });
 
-    test("conversion with an argument", () => {
+    test("conversion with an argument (always)", () => {
         const result = convertSpaceBeforeFunctionParen({
-            ruleArguments: ["anonymous"],
+            ruleArguments: ["always"],
         });
 
         expect(result).toEqual({
             rules: [
                 {
-                    ruleArguments: ["anonymous"],
+                    ruleArguments: ["always"],
+                    ruleName: "space-before-function-paren",
+                },
+            ],
+        });
+    });
+
+    test("conversion with an argument (never)", () => {
+        const result = convertSpaceBeforeFunctionParen({
+            ruleArguments: ["never"],
+        });
+
+        expect(result).toEqual({
+            rules: [
+                {
+                    ruleArguments: ["never"],
+                    ruleName: "space-before-function-paren",
+                },
+            ],
+        });
+    });
+
+    test("conversion with an argument (object)", () => {
+        const result = convertSpaceBeforeFunctionParen({
+            ruleArguments: [{ anonymous: "never" }],
+        });
+
+        expect(result).toEqual({
+            rules: [
+                {
+                    ruleArguments: [{ anonymous: "never" }],
                     ruleName: "space-before-function-paren",
                 },
             ],
@@ -32,7 +62,15 @@ describe(convertSpaceBeforeFunctionParen, () => {
 
     test("conversion with all existing arguments", () => {
         const result = convertSpaceBeforeFunctionParen({
-            ruleArguments: ["anonymous", "named", "asyncArrow", "method", "constructor"],
+            ruleArguments: [
+                {
+                    anonymous: "never",
+                    asyncArrow: "always",
+                    constructor: "never",
+                    method: "never",
+                    named: "never",
+                },
+            ],
         });
 
         expect(result).toEqual({
@@ -42,7 +80,13 @@ describe(convertSpaceBeforeFunctionParen, () => {
                         'Option "constructor" is not supported by ESLint.',
                         'Option "method" is not supported by ESLint.',
                     ],
-                    ruleArguments: ["anonymous", "named", "asyncArrow"],
+                    ruleArguments: [
+                        {
+                            anonymous: "never",
+                            asyncArrow: "always",
+                            named: "never",
+                        },
+                    ],
                     ruleName: "space-before-function-paren",
                 },
             ],
@@ -51,7 +95,12 @@ describe(convertSpaceBeforeFunctionParen, () => {
 
     test('conversion with not supported options ["method", "constructor"]', () => {
         const result = convertSpaceBeforeFunctionParen({
-            ruleArguments: ["method", "constructor"],
+            ruleArguments: [
+                {
+                    constructor: "never",
+                    method: "never",
+                },
+            ],
         });
 
         expect(result).toEqual({
@@ -61,7 +110,6 @@ describe(convertSpaceBeforeFunctionParen, () => {
                         'Option "constructor" is not supported by ESLint.',
                         'Option "method" is not supported by ESLint.',
                     ],
-                    ruleArguments: [],
                     ruleName: "space-before-function-paren",
                 },
             ],