From 73c8059a0a4698ddf724de87b3efdc09dfedd68e Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim.schaub@gmail.com>
Date: Thu, 11 Aug 2016 22:15:06 -0600
Subject: [PATCH] Create rule enforcing that goog.provide() is like the path

---
 package.json             |  1 +
 rules/index.js           |  1 +
 rules/valid-provide.js   | 58 ++++++++++++++++++++++++++++++++++++++++
 test/.eslintrc           |  5 ++++
 test_rendering/.eslintrc |  5 ++++
 5 files changed, 70 insertions(+)
 create mode 100644 rules/valid-provide.js
 create mode 100644 test/.eslintrc
 create mode 100644 test_rendering/.eslintrc

diff --git a/package.json b/package.json
index 32d62aa049..4fb4e22993 100644
--- a/package.json
+++ b/package.json
@@ -102,6 +102,7 @@
       "openlayers-internal/no-unused-requires": 2,
       "openlayers-internal/one-provide": 1,
       "openlayers-internal/requires-first": 2,
+      "openlayers-internal/valid-provide": 2,
       "openlayers-internal/valid-requires": 2
     }
   },
diff --git a/rules/index.js b/rules/index.js
index d4f37de7e0..2b38047b87 100644
--- a/rules/index.js
+++ b/rules/index.js
@@ -7,6 +7,7 @@ module.exports = {
     'no-unused-requires': require('./no-unused-requires').rule,
     'one-provide': require('./one-provide').rule,
     'requires-first': require('./requires-first').rule,
+    'valid-provide': require('./valid-provide').rule,
     'valid-requires': require('./valid-requires').rule
   }
 };
diff --git a/rules/valid-provide.js b/rules/valid-provide.js
new file mode 100644
index 0000000000..35890bad5d
--- /dev/null
+++ b/rules/valid-provide.js
@@ -0,0 +1,58 @@
+'use strict';
+
+const path = require('path');
+const util = require('./util');
+
+const sourceRoot = path.join(__dirname, '..', 'src');
+
+exports.rule = {
+  meta: {
+    docs: {
+      description: 'require the first goog.provide() has an arg named like the file path'
+    }
+  },
+
+  create: function(context) {
+    let gotFirst = false;
+    return {
+      CallExpression: function(expression) {
+        if (gotFirst) {
+          return;
+        }
+        if (util.isProvideExpression(expression)) {
+          gotFirst = true;
+          const parent = expression.parent;
+          if (parent.type !== 'ExpressionStatement') {
+            return context.report(expression, 'Expected goog.provide() to in an expression statement');
+          }
+
+          if (parent.parent.type !== 'Program') {
+            return context.report(expression, 'Expected goog.provide() to be at the top level');
+          }
+
+          if (expression.arguments.length !== 1) {
+            return context.report(expression, 'Expected one argument for goog.require()');
+          }
+
+          const arg = expression.arguments[0];
+          if (arg.type !== 'Literal' || !arg.value || typeof arg.value !== 'string') {
+            return context.report(expression, 'Expected goog.require() to be called with a string');
+          }
+
+          const filePath = path.relative(sourceRoot, context.getFilename());
+          let ext;
+          if (path.basename(filePath) === 'index.js') {
+            ext = path.sep + 'index.js';
+          } else {
+            ext = '.js';
+          }
+          const name = arg.value;
+          const expectedPath = name.split('.').join(path.sep) + ext;
+          if (expectedPath.toLowerCase() !== filePath.toLowerCase()) {
+            return context.report(expression, `Expected goog.provide('${name}') to be like ${filePath}`);
+          }
+        }
+      }
+    };
+  }
+};
diff --git a/test/.eslintrc b/test/.eslintrc
new file mode 100644
index 0000000000..3bd7528f3c
--- /dev/null
+++ b/test/.eslintrc
@@ -0,0 +1,5 @@
+{
+  "rules": {
+    "openlayers-internal/valid-provide": 0
+  }
+}
diff --git a/test_rendering/.eslintrc b/test_rendering/.eslintrc
new file mode 100644
index 0000000000..3bd7528f3c
--- /dev/null
+++ b/test_rendering/.eslintrc
@@ -0,0 +1,5 @@
+{
+  "rules": {
+    "openlayers-internal/valid-provide": 0
+  }
+}