From 3e9d317cb967ba8b76ecb3710a9649bafb6d1e6d Mon Sep 17 00:00:00 2001
From: KingDarBoja <stevenbojato04@gmail.com>
Date: Sun, 9 Aug 2020 15:06:06 -0500
Subject: [PATCH] Add naming-convention merger

---
 src/rules/mergers.ts                          |  2 +
 src/rules/mergers/naming-convention.ts        |  9 ++
 .../mergers/tests/naming-convention.test.ts   | 96 +++++++++++++++++++
 3 files changed, 107 insertions(+)
 create mode 100644 src/rules/mergers/naming-convention.ts
 create mode 100644 src/rules/mergers/tests/naming-convention.test.ts

diff --git a/src/rules/mergers.ts b/src/rules/mergers.ts
index a08bfed5c..667219a2e 100644
--- a/src/rules/mergers.ts
+++ b/src/rules/mergers.ts
@@ -1,6 +1,7 @@
 import { mergeBanTypes } from "./mergers/ban-types";
 import { mergeConsistentTypeAssertions } from "./mergers/consistent-type-assertions";
 import { mergeIndent } from "./mergers/indent";
+import { mergeNamingConvention } from "./mergers/naming-convention";
 import { mergeNoCaller } from "./mergers/no-caller";
 import { mergeNoEval } from "./mergers/no-eval";
 import { mergeNoMemberDelimiterStyle } from "./mergers/member-delimiter-style";
@@ -12,6 +13,7 @@ export const mergers = new Map([
     ["@typescript-eslint/consistent-type-assertions", mergeConsistentTypeAssertions],
     ["@typescript-eslint/indent", mergeIndent],
     ["@typescript-eslint/member-delimiter-style", mergeNoMemberDelimiterStyle],
+    ["@typescript-eslint/naming-convention", mergeNamingConvention],
     ["@typescript-eslint/no-unnecessary-type-assertion", mergeNoUnnecessaryTypeAssertion],
     ["@typescript-eslint/triple-slash-reference", mergeTripleSlashReference],
     ["no-caller", mergeNoCaller],
diff --git a/src/rules/mergers/naming-convention.ts b/src/rules/mergers/naming-convention.ts
new file mode 100644
index 000000000..78b3614b5
--- /dev/null
+++ b/src/rules/mergers/naming-convention.ts
@@ -0,0 +1,9 @@
+import { RuleMerger } from "../merger";
+
+export const mergeNamingConvention: RuleMerger = (existingOptions, newOptions) => {
+    if (existingOptions === undefined && newOptions === undefined) {
+        return [];
+    }
+
+    return [...(existingOptions ?? []), ...(newOptions ?? [])];
+};
diff --git a/src/rules/mergers/tests/naming-convention.test.ts b/src/rules/mergers/tests/naming-convention.test.ts
new file mode 100644
index 000000000..ea5d4cc89
--- /dev/null
+++ b/src/rules/mergers/tests/naming-convention.test.ts
@@ -0,0 +1,96 @@
+import { mergeNamingConvention } from "../naming-convention";
+
+describe(mergeNamingConvention, () => {
+    test("neither options existing", () => {
+        const result = mergeNamingConvention(undefined, undefined);
+
+        expect(result).toEqual([]);
+    });
+
+    test("original variable name existing", () => {
+        const result = mergeNamingConvention(
+            [
+                {
+                    selector: "variable",
+                    format: ["camelCase", "UPPER_CASE"],
+                    leadingUnderscore: "forbid",
+                    trailingUnderscore: "forbid",
+                },
+            ],
+            undefined,
+        );
+
+        expect(result).toEqual([
+            {
+                selector: "variable",
+                format: ["camelCase", "UPPER_CASE"],
+                leadingUnderscore: "forbid",
+                trailingUnderscore: "forbid",
+            },
+        ]);
+    });
+
+    test("original interface name existing", () => {
+        const result = mergeNamingConvention(undefined, [
+            {
+                selector: "interface",
+                format: ["PascalCase"],
+                custom: {
+                    regex: "^I[A-Z]",
+                    match: false,
+                },
+            },
+        ]);
+
+        expect(result).toEqual([
+            {
+                selector: "interface",
+                format: ["PascalCase"],
+                custom: {
+                    regex: "^I[A-Z]",
+                    match: false,
+                },
+            },
+        ]);
+    });
+
+    test("both interface and variable name existing", () => {
+        const result = mergeNamingConvention(
+            [
+                {
+                    selector: "variable",
+                    format: ["camelCase", "UPPER_CASE"],
+                    leadingUnderscore: "forbid",
+                    trailingUnderscore: "forbid",
+                },
+            ],
+            [
+                {
+                    selector: "interface",
+                    format: ["PascalCase"],
+                    custom: {
+                        regex: "^I[A-Z]",
+                        match: false,
+                    },
+                },
+            ],
+        );
+
+        expect(result).toEqual([
+            {
+                selector: "variable",
+                format: ["camelCase", "UPPER_CASE"],
+                leadingUnderscore: "forbid",
+                trailingUnderscore: "forbid",
+            },
+            {
+                selector: "interface",
+                format: ["PascalCase"],
+                custom: {
+                    regex: "^I[A-Z]",
+                    match: false,
+                },
+            },
+        ]);
+    });
+});