Initial scaffolding for the new linter, without any rules implemented…

… yet (#10)

* Initial scaffolding for the new linter, without any rules implemented yet.

Extracted by rictic from usergenic's #1 PR

* Tighten down and standardize tsconfig

* Improve error handling.

We should never crash based on an analysis error, instead we could just turn that error into a warning on the related file.

* Standardize on tslint from analyzer, + the new prefer-const

* Also recover from errors thrown from lint rules.

.clang-format

@@ -0,0 +1,12 @@
+BasedOnStyle: Google
+AlignAfterOpenBracket: AlwaysBreak
+AllowAllParametersOfDeclarationOnNextLine: false
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: None
+AllowShortIfStatementsOnASingleLine: false
+AllowShortLoopsOnASingleLine: false
+BinPackArguments: false
+# This breaks async functions sometimes, see
+#     https://github.com/Polymer/polymer-analyzer/pull/393
+# BinPackParameters: false

.editorconfig

@@ -0,0 +1,19 @@
+# Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
+# This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+# The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+# The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+# Code distributed by Google as part of the polymer project is also
+# subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+
+# Polymer EditorConfig
+
+root = true
+
+[*]
+charset = utf-8
+indent_size = 2
+indent_style = space
+trim_trailing_whitespace = true
+
+[*.md]
+trim_trailing_whitespace = false

.gitignore

@@ -0,0 +1,2 @@
+lib
+node_modules

.npmignore

@@ -0,0 +1,5 @@
+# npmignore
+CHANGELOG.md
+README.md
+node_modules
+test

.vscode/settings.json

@@ -0,0 +1,19 @@
+// Place your settings in this file to overwrite default and user settings.
+{
+  "clang-format.style": "file",
+  "editor.formatOnSave": true,
+  "editor.formatOnType": true,
+  "search.exclude": {
+    "node_modules/": true,
+    "lib/": true
+  },
+  "json.schemas": [
+    {
+      "fileMatch": [
+        "elements.json"
+      ],
+      "url": "./lib/analysis.schema.json"
+    }
+  ],
+  "typescript.tsdk": "node_modules/typescript/lib"
+}

README.md

@@ -1 +1,9 @@
-# polymer-linter
+# Polymer Linter
+
+Catch errors in your Polymer project before even running your code.
+
+## Work in progress
+
+Polymer Linter is being developed to replace [polylint][1], but is not yet complete.  For a working linter, use [polylint][1].
+
+[1]: https://www.github.com/polymerlabs/polylint

package.json

@@ -0,0 +1,41 @@
+{
+  "name": "polymer-linter",
+  "version": "1.0.0-alpha.1",
+  "description": "Lint Polymer!",
+  "main": "lib/linter.js",
+  "dependencies": {
+    "dom5": "^2.0.0",
+    "parse5": "^2.2.1",
+    "polymer-analyzer": "^2.0.0-alpha.14"
+  },
+  "devDependencies": {
+    "@types/mocha": "^2.2.32",
+    "clang-format": "^1.0.45",
+    "mocha": "^3.1.0",
+    "source-map-support": "^0.4.3",
+    "tslint": "^4.1.1",
+    "typescript": "^2.0.3"
+  },
+  "scripts": {
+    "build": "tsc",
+    "clean": "rm -rf lib; mkdir -p lib",
+    "format": "find src | grep '\\.[jt]s$' | xargs clang-format --style=file -i",
+    "lint": "tslint -c tslint.json src/*.ts src/**/*.ts",
+    "test": "npm run format && npm run clean && npm run build && npm run lint && mocha"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/Polymer/polymer-linter.git"
+  },
+  "keywords": [
+    "polymer",
+    "lint",
+    "linter"
+  ],
+  "author": "The Polymer Project authors",
+  "license": "BSD-3-Clause",
+  "bugs": {
+    "url": "https://github.com/Polymer/polymer-linter/issues"
+  },
+  "homepage": "https://github.com/Polymer/polymer-linter#readme"
+}

src/linter.ts

@@ -0,0 +1,91 @@
+/**
+ * @license
+ * Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
+ * This code may only be used under the BSD style license found at
+ * http://polymer.github.io/LICENSE.txt
+ * The complete set of authors may be found at
+ * http://polymer.github.io/AUTHORS.txt
+ * The complete set of contributors may be found at
+ * http://polymer.github.io/CONTRIBUTORS.txt
+ * Code distributed by Google as part of the polymer project is also
+ * subject to an additional IP rights grant found at
+ * http://polymer.github.io/PATENTS.txt
+ */
+
+import {Analyzer} from 'polymer-analyzer';
+import {Severity, Warning, WarningCarryingException} from 'polymer-analyzer/lib/warning/warning';
+
+import {Rule} from './rule';
+
+/**
+ * The Linter is a simple class which groups together a set of Rules and applies
+ * them to a set of file urls which can be resolved and loaded by the provided
+ * Analyzer.  A default Analyzer is prepared if one is not provided.
+ */
+export class Linter {
+  private _analyzer: Analyzer;
+  private _rules: Rule[];
+
+  constructor(rules: Rule[], analyzer: Analyzer) {
+    this._analyzer = analyzer;
+    this._rules = Array.from(rules);
+  }
+
+  /**
+   * Given an array of filenames, lint the files and return an array of all
+   * warnings produced evaluating the linter rules.
+   */
+  public async lint(files: string[]): Promise<Warning[]> {
+    let warnings: Warning[] = [];
+    const analysisResult = await this._analyzeAll(files);
+    const documents = analysisResult.documents;
+    const analysisWarnings = analysisResult.warnings;
+    warnings = warnings.concat(analysisWarnings);
+    for (const document of documents) {
+      for (const rule of this._rules) {
+        try {
+          warnings = warnings.concat(await rule.check(document));
+        } catch (e) {
+          warnings.push(this._getWarningFromError(
+              e,
+              document.url,
+              'internal-lint-error',
+              `Internal error during linting: ${e ? e.message : e}`));
+        }
+      }
+    }
+    return warnings;
+  }
+
+  private async _analyzeAll(files: string[]) {
+    const documents = [];
+    const warnings: Warning[] = [];
+    for (const file of files) {
+      try {
+        documents.push(await this._analyzer.analyze(file));
+      } catch (e) {
+        warnings.push(this._getWarningFromError(
+            e,
+            file,
+            'unable-to-analyze-file',
+            `Internal Error while analyzing: ${e ? e.message : e}`));
+      }
+    }
+
+    return {documents, warnings};
+  }
+
+  private _getWarningFromError(
+      e: any, file: string, code: string, message: string) {
+    if (e instanceof WarningCarryingException) {
+      return e.warning;
+    }
+    return {
+      code,
+      message,
+      severity: Severity.WARNING,
+      sourceRange:
+          {file, start: {line: 0, column: 0}, end: {line: 0, column: 0}}
+    };
+  }
+}

src/rule.ts

@@ -0,0 +1,18 @@
+/**
+ * @license
+ * Copyright (c) 2014 The Polymer Project Authors. All rights reserved.
+ * This code may only be used under the BSD style license found at
+ * http://polymer.github.io/LICENSE.txt
+ * The complete set of authors may be found at
+ * http://polymer.github.io/AUTHORS.txt
+ * The complete set of contributors may be found at
+ * http://polymer.github.io/CONTRIBUTORS.txt
+ * Code distributed by Google as part of the polymer project is also
+ * subject to an additional IP rights grant found at
+ * http://polymer.github.io/PATENTS.txt
+ */
+
+import {Document} from 'polymer-analyzer/lib/model/document';
+import {Warning} from 'polymer-analyzer/lib/warning/warning';
+
+export interface Rule { check(document: Document): Promise<Warning[]>; }

test/mocha.opts

@@ -0,0 +1,3 @@
+--ui tdd
+--require source-map-support/register
+lib/test

tsconfig.json

@@ -0,0 +1,24 @@
+{
+    "compilerOptions": {
+        "target": "es6",
+        "module": "commonjs",
+        "moduleResolution": "node",
+        "isolatedModules": false,
+        "noImplicitAny": true,
+        "noUnusedLocals": true,
+        "noUnusedParameters": true,
+        "noImplicitThis": true,
+        "strictNullChecks": true,
+        "removeComments": false,
+        "preserveConstEnums": true,
+        "suppressImplicitAnyIndexErrors": true,
+        "lib": ["es2017"],
+        "outDir": "./lib",
+        "declaration": true,
+        "sourceMap": true,
+        "pretty": true
+    },
+    "include": [
+        "src/**/*.ts"
+    ]
+}

tslint.json

@@ -0,0 +1,59 @@
+{
+    "rules": {
+        "class-name": true,
+        "indent": [
+            true,
+            "spaces"
+        ],
+        "prefer-const": true,
+        "no-duplicate-variable": true,
+        "no-eval": true,
+        "no-internal-module": true,
+        "no-trailing-whitespace": true,
+        "no-var-keyword": true,
+        "one-line": [
+            true,
+            "check-open-brace",
+            "check-whitespace"
+        ],
+        "quotemark": [
+            true,
+            "single",
+            "avoid-escape"
+        ],
+        "semicolon": [
+            true,
+            "always"
+        ],
+        "trailing-comma": [
+            true,
+            "multiline"
+        ],
+        "triple-equals": [
+            true,
+            "allow-null-check"
+        ],
+        "typedef-whitespace": [
+            true,
+            {
+                "call-signature": "nospace",
+                "index-signature": "nospace",
+                "parameter": "nospace",
+                "property-declaration": "nospace",
+                "variable-declaration": "nospace"
+            }
+        ],
+        "variable-name": [
+            true,
+            "ban-keywords"
+        ],
+        "whitespace": [
+            true,
+            "check-branch",
+            "check-decl",
+            "check-operator",
+            "check-separator",
+            "check-type"
+        ]
+    }
+}