From aba6408d3d28dbe6b203963a2fb69cfb67e44ec2 Mon Sep 17 00:00:00 2001
From: d0whc3r <d0whc3r@gmail.com>
Date: Sun, 15 Sep 2019 17:30:36 +0200
Subject: [PATCH] feat(own-methods-must-be-private): add new rule

---
 README.md                                     |  5 ++
 docs/own-methods-must-be-private.md           | 15 ++++++
 src/configs/recommended.ts                    |  1 +
 src/rules/index.ts                            |  2 +
 src/rules/own-methods-must-be-private.ts      | 48 +++++++++++++++++++
 src/utils.ts                                  | 12 +++++
 .../own-methods-must-be-private.good.tsx      | 18 +++++++
 .../own-methods-must-be-private.spec.ts       | 27 +++++++++++
 .../own-methods-must-be-private.wrong.tsx     | 27 +++++++++++
 9 files changed, 155 insertions(+)
 create mode 100644 docs/own-methods-must-be-private.md
 create mode 100644 src/rules/own-methods-must-be-private.ts
 create mode 100644 tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.good.tsx
 create mode 100644 tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.spec.ts
 create mode 100644 tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.wrong.tsx

diff --git a/README.md b/README.md
index d6afd92..114ee18 100644
--- a/README.md
+++ b/README.md
@@ -63,6 +63,10 @@ This rule catches Stencil Methods marked as private or protected.
 
 This rule catches Stencil Watchs with non existing Props or States.
 
+- [`@d0whc3r/stencil/own-methods-must-be-private`](./docs/own-methods-must-be-private.md)
+
+This rule catches own class methods marked as public.
+
 - [`@d0whc3r/stencil/own-props-must-be-private`](./docs/own-props-must-be-private.md)
 
 This rule catches own class properties marked as public.
@@ -120,6 +124,7 @@ This rule catches modules that expose more than just the Stencil Component itsel
   "@d0whc3r/stencil/host-data-deprecated": "error",
   "@d0whc3r/stencil/methods-must-be-public": "error",
   "@d0whc3r/stencil/no-unused-watch": "error",
+  "@d0whc3r/stencil/own-methods-must-be-private": "error",
   "@d0whc3r/stencil/own-props-must-be-private": "error",
   "@d0whc3r/stencil/prefer-vdom-listener": "error",
   "@d0whc3r/stencil/props-must-be-public": "error",
diff --git a/docs/own-methods-must-be-private.md b/docs/own-methods-must-be-private.md
new file mode 100644
index 0000000..fcf77ef
--- /dev/null
+++ b/docs/own-methods-must-be-private.md
@@ -0,0 +1,15 @@
+# own-methods-must-be-private
+
+Ensures that all own class properties are private.
+
+## Config
+
+No config is needed
+
+## Usage
+
+```json
+{ "@d0whc3r/stencil/own-methods-must-be-private": "error" }
+```
+
+> Fix included
diff --git a/src/configs/recommended.ts b/src/configs/recommended.ts
index 300e9cc..04f622a 100644
--- a/src/configs/recommended.ts
+++ b/src/configs/recommended.ts
@@ -28,6 +28,7 @@ export default {
         '@d0whc3r/stencil/host-data-deprecated': 'error',
         '@d0whc3r/stencil/methods-must-be-public': 'error',
         '@d0whc3r/stencil/no-unused-watch': 'error',
+        '@d0whc3r/stencil/own-methods-must-be-private': 'error',
         '@d0whc3r/stencil/own-props-must-be-private': 'error',
         '@d0whc3r/stencil/prefer-vdom-listener': 'error',
         '@d0whc3r/stencil/props-must-be-public': 'error',
diff --git a/src/rules/index.ts b/src/rules/index.ts
index 2a00938..757aaf0 100644
--- a/src/rules/index.ts
+++ b/src/rules/index.ts
@@ -7,6 +7,7 @@ import elementType from './element-type';
 import hostDataDeprecated from './host-data-deprecated';
 import methodsMustBePublic from './methods-must-be-public';
 import noUnusedWatch from './no-unused-watch';
+import ownMethodsMustBePrivate from './own-methods-must-be-private';
 import ownPropsMustBePrivate from './own-props-must-be-private';
 import preferVdomListener from './prefer-vdom-listener';
 import propsMustBePublic from './props-must-be-public';
@@ -27,6 +28,7 @@ export default {
   'host-data-deprecated': hostDataDeprecated,
   'methods-must-be-public': methodsMustBePublic,
   'no-unused-watch': noUnusedWatch,
+  'own-methods-must-be-private': ownMethodsMustBePrivate,
   'own-props-must-be-private': ownPropsMustBePrivate,
   'prefer-vdom-listener': preferVdomListener,
   'props-must-be-public': propsMustBePublic,
diff --git a/src/rules/own-methods-must-be-private.ts b/src/rules/own-methods-must-be-private.ts
new file mode 100644
index 0000000..5a8d1f3
--- /dev/null
+++ b/src/rules/own-methods-must-be-private.ts
@@ -0,0 +1,48 @@
+import { Rule } from 'eslint';
+import ts from 'typescript';
+import { isPrivate, stencilComponentContext, stencilDecorators, stencilLifecycle } from '../utils';
+
+const rule: Rule.RuleModule = {
+  meta: {
+    docs: {
+      description: 'This rule catches own class methods marked as public.',
+      category: 'Possible Errors',
+      recommended: true
+    },
+    schema: [],
+    type: 'problem',
+    fixable: 'code'
+  },
+
+  create(context): Rule.RuleListener {
+    const stencil = stencilComponentContext();
+
+    const parserServices = context.parserServices;
+    return {
+      ...stencil.rules,
+      'MethodDefinition': (node: any) => {
+        if (!stencil.isComponent()) {
+          return;
+        }
+        const originalNode = parserServices.esTreeNodeToTSNodeMap.get(node);
+        const stencilDecorator = originalNode.decorators && originalNode.decorators.some(
+            (dec: any) => stencilDecorators.includes(dec.expression.expression.escapedText));
+        const stencilCycle = stencilLifecycle.includes(originalNode.name.escapedText);
+        if (!stencilDecorator && !stencilCycle && !isPrivate(originalNode)) {
+          const text = String(originalNode.getFullText());
+          context.report({
+            node: node,
+            message: `Own class methods cannot be public`,
+            fix(fixer) {
+              const methodName = node.key.name;
+              const result = text.replace('public ', '').replace(methodName, `private ${methodName}`);
+              return fixer.replaceText(node, result);
+            }
+          });
+        }
+      }
+    };
+  }
+};
+
+export default rule;
diff --git a/src/utils.ts b/src/utils.ts
index b1b8099..89ba0f8 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -59,3 +59,15 @@ export function getType(node: any) {
 }
 
 export const stencilDecorators = ['Component', 'Prop', 'State', 'Watch', 'Element', 'Method', 'Event', 'Listen'];
+
+export const stencilLifecycle = [
+  'connectedCallback',
+  'disconnectedCallback',
+  'componentWillLoad',
+  'componentDidLoad',
+  'componentWillRender',
+  'componentDidRender',
+  'componentWillUpdate',
+  'componentDidUpdate',
+  'render'
+];
diff --git a/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.good.tsx b/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.good.tsx
new file mode 100644
index 0000000..523463e
--- /dev/null
+++ b/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.good.tsx
@@ -0,0 +1,18 @@
+@Component({ tag: 'sample-tag' })
+export class SampleTag {
+  @Prop() readonly test?: string;
+  @Prop({ mutable: true }) testMutable?: string;
+
+  private internalMethod() {
+    return 'ok';
+  }
+
+  @OwnDecorator()
+  private internalDecoratedMethod() {
+    return 'ok';
+  };
+
+  render() {
+    return (<div>test</div>);
+  }
+}
diff --git a/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.spec.ts b/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.spec.ts
new file mode 100644
index 0000000..503ea55
--- /dev/null
+++ b/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.spec.ts
@@ -0,0 +1,27 @@
+import rule from '../../../../src/rules/own-methods-must-be-private';
+import { ruleTester } from '../rule-tester';
+import * as path from 'path';
+import * as fs from 'fs';
+
+describe('stencil rules', () => {
+  const files = {
+    good: path.resolve(__dirname, 'own-methods-must-be-private.good.tsx'),
+    wrong: path.resolve(__dirname, 'own-methods-must-be-private.wrong.tsx')
+  };
+  ruleTester.run('own-methods-must-be-private', rule, {
+    valid: [
+      {
+        code: fs.readFileSync(files.good, 'utf8'),
+        filename: files.good
+      }
+    ],
+
+    invalid: [
+      {
+        code: fs.readFileSync(files.wrong, 'utf8'),
+        filename: files.wrong,
+        errors: 4
+      }
+    ]
+  });
+});
diff --git a/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.wrong.tsx b/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.wrong.tsx
new file mode 100644
index 0000000..a4a3837
--- /dev/null
+++ b/tests/lib/rules/own-methods-must-be-private/own-methods-must-be-private.wrong.tsx
@@ -0,0 +1,27 @@
+@Component({ tag: 'sample-tag' })
+export class SampleTag {
+  @Prop() readonly test?: string;
+  @Prop({ mutable: true }) testMutable?: string;
+
+  internalMethod() {
+    return 'ok';
+  }
+
+  public internalMethod2() {
+    return 'ok';
+  }
+
+  @OwnDecorator()
+  internalDecoratedMethod() {
+    return 'ok';
+  };
+
+  @OwnDecorator()
+  public internalDecoratedMethod2() {
+    return 'ok';
+  };
+
+  render() {
+    return (<div>test</div>);
+  }
+}