feat(ast-spec): add fixtures

Add fixture tests for each and every AST node.
To make things more readable I:
- separated the AST from the tokens
  - this stops the individual snapshot from being so long it's impossible to understand
  - if there are changes to tokens - then they should be more obvious now. Before you had to expand the snapshot in github to understand that the token was part of the tokens array.
- always write error snapshot, and always write AST/token snapshots
  - This is just for consistency and to make it easier whilst you're developing.
  - It will prevent us from accidentally leaving behind error snapshots if they weren't supposed to be there.
- added a custom snapshot serializer
  - Having learned how useful they are with scope manager - I created a new one to improve the look of the snapshots.
  - Instead of sorting alphabetically, I place `type` at the top, and `range`/`loc` at the end.
  - Instead of outputting `Object` ahead of every node, instead it outputs the node `type`.
  - I adjusted the output `range`/`loc` so they take up fewer lines and are more compact.

I prefixed the snapshot names with numbers just so we can control the sorting of them. No other reason.

.github/workflows/ci.yml

@@ -96,6 +96,12 @@ jobs:
           # Website will be built by the Netlify GitHub App
           yarn build --exclude website
 
+      - name: Run unit tests for ast-spec
+        run: yarn test
+        working-directory: packages/ast-spec
+        env:
+          CI: true
+
       - name: Run unit tests for typescript-estree
         run: npx nx test @typescript-eslint/typescript-estree
         env:
@@ -308,6 +314,7 @@ jobs:
         env:
           CI: true
 
+      # ast-spec is internal only - so don't care about compat on other versions
       # eslint-plugin-internal is internal only - so don't care about compat on other versions
 
   website_tests:

.prettierignore

@@ -12,6 +12,7 @@ packages/eslint-plugin-tslint/tests/test-tslint-rules-directory/alwaysFailRule.j
 packages/eslint-plugin/src/configs/*.json
 .all-contributorsrc
 CONTRIBUTORS.md
+packages/ast-spec/src/*/*/fixtures/_error_/*/fixture.ts
 
 # Ignore CHANGELOG.md files to avoid issues with automated release job
 CHANGELOG.md

.vscode/launch.json

@@ -242,5 +242,37 @@
         "${workspaceFolder}/packages/scope-manager/dist/index.js",
       ],
     },
+    {
+      "type": "node",
+      "request": "launch",
+      "name": "Run currently opened ast-spec test",
+      "cwd": "${workspaceFolder}/packages/ast-spec/",
+      "program": "${workspaceFolder}/node_modules/jest/bin/jest.js",
+      "args": [
+        "--runInBand",
+        "--no-cache",
+        "--no-coverage",
+        "${fileBasename}"
+      ],
+      "sourceMaps": true,
+      "console": "integratedTerminal",
+      "internalConsoleOptions": "neverOpen",
+      "skipFiles": [
+        "${workspaceFolder}/packages/experimental-utils/src/index.ts",
+        "${workspaceFolder}/packages/experimental-utils/dist/index.js",
+        "${workspaceFolder}/packages/experimental-utils/src/ts-estree.ts",
+        "${workspaceFolder}/packages/experimental-utils/dist/ts-estree.js",
+        "${workspaceFolder}/packages/parser/src/index.ts",
+        "${workspaceFolder}/packages/parser/dist/index.js",
+        "${workspaceFolder}/packages/typescript-estree/src/index.ts",
+        "${workspaceFolder}/packages/typescript-estree/dist/index.js",
+        "${workspaceFolder}/packages/types/src/index.ts",
+        "${workspaceFolder}/packages/types/dist/index.js",
+        "${workspaceFolder}/packages/visitor-keys/src/index.ts",
+        "${workspaceFolder}/packages/visitor-keys/dist/index.js",
+        "${workspaceFolder}/packages/scope-manager/dist/index.js",
+        "${workspaceFolder}/packages/scope-manager/dist/index.js",
+      ],
+    },
   ]
 }

.vscode/settings.json

@@ -27,10 +27,7 @@
     {
         "icon": "jest_snapshot",
         "extensions": [
-            ".ts.shot",
-            ".tsx.shot",
-            ".js.shot",
-            ".jsx.shot",
+            ".shot",
         ],
         "extends": "jest_snapshot"
     },

package.json

@@ -55,6 +55,10 @@
     "node": "^12.22.0 || ^14.17.0 || >=16.0.0"
   },
   "devDependencies": {
+    "@babel/code-frame": "^7.14.5",
+    "@babel/eslint-parser": "^7.15.4",
+    "@babel/parser": "^7.15.7",
+    "@babel/types": "^7.15.6",
     "@commitlint/cli": "^16.0.1",
     "@commitlint/config-conventional": "^16.0.0",
     "@nrwl/cli": "13.8.5",
@@ -63,6 +67,7 @@
     "@nrwl/workspace": "13.8.5",
     "@swc/core": "^1.2.159",
     "@swc/jest": "^0.2.20",
+    "@types/babel__code-frame": "^7.0.3",
     "@types/debug": "^4.1.7",
     "@types/eslint-visitor-keys": "^1.0.0",
     "@types/glob": "^7.2.0",
@@ -93,6 +98,8 @@
     "glob": "^8.0.1",
     "husky": "^7.0.4",
     "jest": "^27.3.1",
+    "jest-diff": "^27.3.1",
+    "jest-snapshot": "^27.3.1",
     "jest-specific-snapshot": "^5.0.0",
     "lerna": "^4.0.0",
     "lint-staged": "^12.0.2",

packages/ast-spec/jest.config.js

@@ -5,4 +5,9 @@
 module.exports = {
   ...require('../../jest.config.base.js'),
   testRegex: ['./tests/.+\\.test\\.ts$'],
+  collectCoverage: false,
+  collectCoverageFrom: ['src/**/*.{js,jsx,ts,tsx}'],
+  moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
+  coverageReporters: ['text-summary', 'lcov'],
+  setupFilesAfterEnv: ['./tests/util/setupJest.ts'],
 };

packages/ast-spec/package.json

@@ -32,16 +32,28 @@
     "build": "tsc -b tsconfig.build.json && api-extractor run --local",
     "clean": "tsc -b tsconfig.build.json --clean",
     "postclean": "rimraf dist && rimraf _ts3.4 && rimraf .rollup.cache && rimraf coverage",
+    "clean-fixtures": "rimraf -g \"./src/**/fixtures/**/snapshots\"",
     "format": "prettier --write \"./**/*.{ts,js,json,md}\" --ignore-path ../../.prettierignore",
     "lint": "eslint . --ext .js,.ts --ignore-path='../../.eslintignore'",
+    "test": "jest",
     "typecheck": "tsc -p tsconfig.json --noEmit"
   },
   "funding": {
     "type": "opencollective",
     "url": "https://opencollective.com/typescript-eslint"
   },
   "devDependencies": {
+    "@babel/core": "*",
+    "@babel/eslint-parser": "*",
+    "@babel/parser": "*",
     "@microsoft/api-extractor": "^7.18.16",
+    "@types/babel__core": "*",
+    "glob": "*",
+    "jest-diff": "*",
+    "jest-snapshot": "*",
+    "jest-specific-snapshot": "*",
+    "make-dir": "*",
+    "pretty-format": "*",
     "typescript": "*"
   }
 }

packages/ast-spec/src/base/TSHeritageBase.ts

@@ -3,6 +3,7 @@ import type { Expression } from '../unions/Expression';
 import type { BaseNode } from './BaseNode';
 
 export interface TSHeritageBase extends BaseNode {
+  // TODO(error handling) - this should be restricted to MemberExpression | Identifier
   expression: Expression;
   typeParameters?: TSTypeParameterInstantiation;
 }

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/implements-non-identifier/fixture.ts

@@ -0,0 +1 @@
+class Foo implements 'thing' {}

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/implements-non-identifier/snapshots/1-TSESTree-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ implements-non-identifier TSESTree - Error 1`] = `"NO ERROR"`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/implements-non-identifier/snapshots/2-Babel-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ implements-non-identifier Babel - Error 1`] = `[SyntaxError: Unexpected token (1:21)]`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/implements-non-identifier/snapshots/3-Alignment-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ implements-non-identifier Error Alignment 1`] = `"Babel errored but TSESTree didn't"`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/fixture.ts

@@ -0,0 +1 @@
+class Foo;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/1-TSESTree-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ no-body TSESTree - Error 1`] = `[TSError: '{' expected.]`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/2-Babel-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ no-body Babel - Error 1`] = `[SyntaxError: Unexpected token, expected "{" (1:9)]`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/no-body/snapshots/3-Alignment-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ no-body Error Alignment 1`] = `"Both errored"`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-name/fixture.ts

@@ -0,0 +1 @@
+class 'Foo' {}

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-name/snapshots/1-TSESTree-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ non-identifier-name TSESTree - Error 1`] = `[TSError: '{' expected.]`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-name/snapshots/2-Babel-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ non-identifier-name Babel - Error 1`] = `[SyntaxError: A class name is required. (1:6)]`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/_error_/non-identifier-name/snapshots/3-Alignment-Error.shot

@@ -0,0 +1,3 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration _error_ non-identifier-name Error Alignment 1`] = `"Both errored"`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/abstract/fixture.ts

@@ -0,0 +1 @@
+abstract class Foo {}

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/abstract/snapshots/1-TSESTree-AST.shot

@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration abstract TSESTree - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ClassDeclaration {
+      type: "ClassDeclaration",
+      abstract: true,
+      body: ClassBody {
+        type: "ClassBody",
+        body: Array [],
+
+        range: [19, 21],
+        loc: {
+          start: { column: 19, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [15, 18],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      superClass: null,
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/abstract/snapshots/2-TSESTree-Tokens.shot

@@ -0,0 +1,56 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration abstract TSESTree - Tokens 1`] = `
+Array [
+  Identifier {
+    type: "Identifier",
+    value: "abstract",
+
+    range: [0, 8],
+    loc: {
+      start: { column: 0, line: 1 },
+      end: { column: 8, line: 1 },
+    },
+  },
+  Keyword {
+    type: "Keyword",
+    value: "class",
+
+    range: [9, 14],
+    loc: {
+      start: { column: 9, line: 1 },
+      end: { column: 14, line: 1 },
+    },
+  },
+  Identifier {
+    type: "Identifier",
+    value: "Foo",
+
+    range: [15, 18],
+    loc: {
+      start: { column: 15, line: 1 },
+      end: { column: 18, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "{",
+
+    range: [19, 20],
+    loc: {
+      start: { column: 19, line: 1 },
+      end: { column: 20, line: 1 },
+    },
+  },
+  Punctuator {
+    type: "Punctuator",
+    value: "}",
+
+    range: [20, 21],
+    loc: {
+      start: { column: 20, line: 1 },
+      end: { column: 21, line: 1 },
+    },
+  },
+]
+`;

packages/ast-spec/src/declaration/ClassDeclaration/fixtures/abstract/snapshots/3-Babel-AST.shot

@@ -0,0 +1,47 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`AST Fixtures declaration ClassDeclaration abstract Babel - AST 1`] = `
+Program {
+  type: "Program",
+  body: Array [
+    ClassDeclaration {
+      type: "ClassDeclaration",
+      abstract: true,
+      body: ClassBody {
+        type: "ClassBody",
+        body: Array [],
+
+        range: [19, 21],
+        loc: {
+          start: { column: 19, line: 1 },
+          end: { column: 21, line: 1 },
+        },
+      },
+      id: Identifier {
+        type: "Identifier",
+        name: "Foo",
+
+        range: [15, 18],
+        loc: {
+          start: { column: 15, line: 1 },
+          end: { column: 18, line: 1 },
+        },
+      },
+      superClass: null,
+
+      range: [0, 21],
+      loc: {
+        start: { column: 0, line: 1 },
+        end: { column: 21, line: 1 },
+      },
+    },
+  ],
+  sourceType: "script",
+
+  range: [0, 22],
+  loc: {
+    start: { column: 0, line: 1 },
+    end: { column: 0, line: 2 },
+  },
+}
+`;