fix(no-large-snapshots): support inline snapshots (#186)

Author: JohanBrorson

docs/rules/no-large-snapshots.md

@@ -22,9 +22,10 @@ parserOptions: {
 
 ## Rule Details
 
-This rule looks at all Jest snapshot files (files with `.snap` extension) and
-validates that each stored snapshot within those files does not exceed 50 lines
-(by default, this is configurable as explained in `Options` section below).
+This rule looks at all Jest inline and external snapshots (files with `.snap`
+extension) and validates that each stored snapshot within those files does not
+exceed 50 lines (by default, this is configurable as explained in `Options`
+section below).
 
 Example of **incorrect** code for this rule:
 

rules/__tests__/no-large-snapshots.test.js

@@ -1,6 +1,57 @@
 'use strict';
 
-const noLargeSnapshots = require('../no-large-snapshots').create;
+const RuleTester = require('eslint').RuleTester;
+const rule = require('../no-large-snapshots');
+const noLargeSnapshots = rule.create;
+
+const ruleTester = new RuleTester({
+  parserOptions: {
+    ecmaVersion: 2015,
+  },
+});
+
+ruleTester.run('no-large-snapshots', rule, {
+  valid: [
+    {
+      filename: 'mock.js',
+      code: `expect(something).toMatchInlineSnapshot(\`\n${'line\n'.repeat(
+        2
+      )}\`);`,
+    },
+    {
+      filename: 'mock.js',
+      code: `expect(something).toThrowErrorMatchingInlineSnapshot(\`\n${'line\n'.repeat(
+        2
+      )}\`);`,
+    },
+  ],
+  invalid: [
+    {
+      filename: 'mock.js',
+      code: `expect(something).toMatchInlineSnapshot(\`\n${'line\n'.repeat(
+        50
+      )}\`);`,
+      errors: [
+        {
+          message:
+            'Expected Jest snapshot to be smaller than 50 lines but was 51 lines long',
+        },
+      ],
+    },
+    {
+      filename: 'mock.js',
+      code: `expect(something).toThrowErrorMatchingInlineSnapshot(\`\n${'line\n'.repeat(
+        50
+      )}\`);`,
+      errors: [
+        {
+          message:
+            'Expected Jest snapshot to be smaller than 50 lines but was 51 lines long',
+        },
+      ],
+    },
+  ],
+});
 
 // was not able to use https://eslint.org/docs/developer-guide/nodejs-api#ruletester for these because there is no way to configure RuleTester to run non .js files
 describe('no-large-snapshots', () => {

rules/no-large-snapshots.js

@@ -2,6 +2,27 @@
 
 const getDocsUrl = require('./util').getDocsUrl;
 
+const reportOnViolation = (context, node) => {
+  const lineLimit =
+    context.options[0] && Number.isFinite(context.options[0].maxSize)
+      ? context.options[0].maxSize
+      : 50;
+  const startLine = node.loc.start.line;
+  const endLine = node.loc.end.line;
+  const lineCount = endLine - startLine;
+
+  if (lineCount > lineLimit) {
+    context.report({
+      message:
+        lineLimit === 0
+          ? 'Expected to not encounter a Jest snapshot but was found with {{ lineCount }} lines long'
+          : 'Expected Jest snapshot to be smaller than {{ lineLimit }} lines but was {{ lineCount }} lines long',
+      data: { lineLimit, lineCount },
+      node,
+    });
+  }
+};
+
 module.exports = {
   meta: {
     docs: {
@@ -10,26 +31,21 @@ module.exports = {
   },
   create(context) {
     if (context.getFilename().endsWith('.snap')) {
-      const lineLimit =
-        context.options[0] && Number.isFinite(context.options[0].maxSize)
-          ? context.options[0].maxSize
-          : 50;
-
       return {
         ExpressionStatement(node) {
-          const startLine = node.loc.start.line;
-          const endLine = node.loc.end.line;
-          const lineCount = endLine - startLine;
-
-          if (lineCount > lineLimit) {
-            context.report({
-              message:
-                lineLimit === 0
-                  ? 'Expected to not encounter a Jest snapshot but was found with {{ lineCount }} lines long'
-                  : 'Expected Jest snapshot to be smaller than {{ lineLimit }} lines but was {{ lineCount }} lines long',
-              data: { lineLimit, lineCount },
-              node,
-            });
+          reportOnViolation(context, node);
+        },
+      };
+    } else if (context.getFilename().endsWith('.js')) {
+      return {
+        CallExpression(node) {
+          const propertyName =
+            node.callee.property && node.callee.property.name;
+          if (
+            propertyName === 'toMatchInlineSnapshot' ||
+            propertyName === 'toThrowErrorMatchingInlineSnapshot'
+          ) {
+            reportOnViolation(context, node);
           }
         },
       };