fix: allow import.meta.env.SSR check (#122)

* fix: account for import.meta.env.SSR for SSR * fix: add example in docs
salesforce · Jun 21, 2023 · 8e526d2 · 8e526d2
1 parent 6dd691f
commit 8e526d2
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Showing 3 changed files with 132 additions and 6 deletions.
diff --git a/docs/rules/no-restricted-browser-globals-during-ssr.md b/docs/rules/no-restricted-browser-globals-during-ssr.md
@@ -31,6 +31,18 @@ export default class Foo extends LightningElement {
 }
 ```
 
+```js
+import { LightningElement } from 'lwc';
+
+export default class Foo extends LightningElement {
+    renderedCallback() {
+        if (!import.meta.env.SSR) {
+            const parser = new DOMParser();
+        }
+    }
+}
+```
+
 ## Options
 
 The rule takes one option, an object, which has one key `restricted-globals` which is an object. The keys in the object

diff --git a/lib/util/ssr.js b/lib/util/ssr.js
@@ -7,13 +7,56 @@
 'use strict';
 
 module.exports.isSSREscape = function isSSREscape(node) {
-    // TODO(117): replace this with `imports.meta.env` when we land support for that.
     return (
         node.type === 'IfStatement' &&
-        node.test.type === 'BinaryExpression' &&
-        node.test.left.type === 'UnaryExpression' &&
-        node.test.left.operator === 'typeof' &&
-        node.test.left.argument.type === 'Identifier' &&
-        (node.test.left.argument.name === 'document' || node.test.left.argument.name === 'window')
+        (isMetaEnvCheck(node.test) || isWindowOrDocumentCheck(node.test))
     );
 };
+
+function isMetaEnvCheck(test) {
+    let node = test;
+    if (!(node.type === 'UnaryExpression' && node.operator === '!')) return false;
+
+    node = node.argument;
+    if (
+        !(
+            node.type === 'MemberExpression' &&
+            node.property.type === 'Identifier' &&
+            node.property.name === 'SSR'
+        )
+    )
+        return false;
+
+    node = node.object;
+    if (
+        !(
+            node.type === 'MemberExpression' &&
+            node.property.type === 'Identifier' &&
+            node.property.name === 'env'
+        )
+    )
+        return false;
+
+    node = node.object; // .meta is not a MemberExpression, it's a MetaProperty in eslint
+    if (
+        !(
+            node.type === 'MetaProperty' &&
+            node.property.type === 'Identifier' &&
+            node.property.name === 'meta'
+        )
+    )
+        return false;
+
+    node = node.meta;
+    return node.type && node.name === 'import';
+}
+
+function isWindowOrDocumentCheck(node) {
+    return (
+        node.type === 'BinaryExpression' &&
+        node.left.type === 'UnaryExpression' &&
+        node.left.operator === 'typeof' &&
+        node.left.argument.type === 'Identifier' &&
+        (node.left.argument.name === 'document' || node.left.argument.name === 'window')
+    );
+}
diff --git a/test/lib/rules/no-restricted-browser-globals-during-ssr.js b/test/lib/rules/no-restricted-browser-globals-during-ssr.js
@@ -166,6 +166,19 @@ tester.run('no-browser-globals-during-ssr', rule, {
               }
           `,
         },
+        {
+            code: `
+              import { LightningElement } from 'lwc';
+
+              export default class Foo extends LightningElement {
+                connectedCallback() {
+                  if(!import.meta.env.SSR) {
+                    window.x = 1;
+                  }
+                }
+              }
+          `,
+        },
         { code: `const f = new Foo();` },
         { code: `const name = new Foo();` },
         {
@@ -394,5 +407,63 @@ tester.run('no-browser-globals-during-ssr', rule, {
                 },
             ],
         },
+
+        {
+            code: `
+              import { LightningElement } from 'lwc';
+
+              export default class Foo extends LightningElement {
+                connectedCallback() {
+                  if(!import.meta.env.notSSR) {
+                    window.x = 1;
+                  }
+                }
+              }
+          `,
+            errors: [
+                {
+                    messageId: 'prohibitedBrowserAPIUsage',
+                    data: { identifier: 'window' },
+                },
+            ],
+        },
+        {
+            code: `
+              import { LightningElement } from 'lwc';
+
+              export default class Foo extends LightningElement {
+                connectedCallback() {
+                  if(!import.meta.notenv.SSR) {
+                    window.x = 1;
+                  }
+                }
+              }
+          `,
+            errors: [
+                {
+                    messageId: 'prohibitedBrowserAPIUsage',
+                    data: { identifier: 'window' },
+                },
+            ],
+        },
+        {
+            code: `
+              import { LightningElement } from 'lwc';
+
+              export default class Foo extends LightningElement {
+                connectedCallback() {
+                  if(!notimport.meta.env.SSR) {
+                    window.x = 1;
+                  }
+                }
+              }
+          `,
+            errors: [
+                {
+                    messageId: 'prohibitedBrowserAPIUsage',
+                    data: { identifier: 'window' },
+                },
+            ],
+        },
     ],
 });