tools: replace closure-linter with eslint

PR-URL: https://github.com/iojs/io.js/pull/1539
Fixes: https://github.com/iojs/io.js/issues/1253
Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com>
Reviewed-By: Trevor Norris <trev.norris@gmail.com>
Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: Chris Dickinson <christopher.s.dickinson@gmail.com>
Reviewed-By: Johan Bergström <bugs@bergstroem.nu>
Reviewed-By: Fedor Indutny <fedor.indutny@gmail.com>

1 files changed, 121 insertions, 0 deletions

diff --git a/tools/eslint/lib/rules/newline-after-var.js b/tools/eslint/lib/rules/newline-after-var.js
new file mode 100644
index 0000000000..7a6c3cff2f
--- /dev/null
+++ b/tools/eslint/lib/rules/newline-after-var.js
@@ -0,0 +1,121 @@
+/**
+ * @fileoverview Rule to check empty newline after "var" statement
+ * @author Gopal Venkatesan
+ * @copyright 2015 Gopal Venkatesan. All rights reserved.
+ * @copyright 2015 Casey Visco. All rights reserved.
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Rule Definition
+//------------------------------------------------------------------------------
+
+module.exports = function(context) {
+
+    var ALWAYS_MESSAGE = "Expected blank line after variable declarations.",
+        NEVER_MESSAGE = "Unexpected blank line after variable declarations.";
+
+    // Default `mode` to "always". This means that invalid options will also
+    // be treated as "always" and the only special case is "never"
+    var mode = context.options[0] === "never" ? "never" : "always";
+
+    // Cache line numbers of comments for faster lookup
+    var comments = context.getAllComments().map(function (token) {
+        return token.loc.start.line;
+    });
+
+
+    //--------------------------------------------------------------------------
+    // Helpers
+    //--------------------------------------------------------------------------
+
+    /**
+     * Determine if provided keyword is a variable declaration
+     * @private
+     * @param {string} keyword - keyword to test
+     * @returns {boolean} True if `keyword` is a type of var
+     */
+    function isVar(keyword) {
+        return keyword === "var" || keyword === "let" || keyword === "const";
+    }
+
+    /**
+     * Determine if provided keyword is a variant of for specifiers
+     * @private
+     * @param {string} keyword - keyword to test
+     * @returns {boolean} True if `keyword` is a variant of for specifier
+     */
+    function isForTypeSpecifier(keyword) {
+        return keyword === "ForStatement" || keyword === "ForInStatement" || keyword === "ForOfStatement";
+    }
+
+    /**
+     * Determine if provided keyword is an export specifiers
+     * @private
+     * @param {string} nodeType - nodeType to test
+     * @returns {boolean} True if `nodeType` is an export specifier
+     */
+    function isExportSpecifier(nodeType) {
+        return nodeType === "ExportNamedDeclaration" || nodeType === "ExportSpecifier" ||
+            nodeType === "ExportDefaultDeclaration" || nodeType === "ExportAllDeclaration";
+    }
+
+    /**
+     * Checks that a blank line exists after a variable declaration when mode is
+     * set to "always", or checks that there is no blank line when mode is set
+     * to "never"
+     * @private
+     * @param {ASTNode} node - `VariableDeclaration` node to test
+     * @returns {void}
+     */
+    function checkForBlankLine(node) {
+        var lastToken = context.getLastToken(node),
+            nextToken = context.getTokenAfter(node),
+            nextLineNum = lastToken.loc.end.line + 1,
+            noNextLineToken,
+            hasNextLineComment;
+
+        // Ignore if there is no following statement
+        if (!nextToken) {
+            return;
+        }
+
+        // Ignore if parent of node is a for variant
+        if (isForTypeSpecifier(node.parent.type)) {
+            return;
+        }
+
+        // Ignore if parent of node is an export specifier
+        if (isExportSpecifier(node.parent.type)) {
+            return;
+        }
+
+        // Some coding styles use multiple `var` statements, so do nothing if
+        // the next token is a `var` statement.
+        if (nextToken.type === "Keyword" && isVar(nextToken.value)) {
+            return;
+        }
+
+        // Next statement is not a `var`...
+        noNextLineToken = nextToken.loc.start.line > nextLineNum;
+        hasNextLineComment = comments.indexOf(nextLineNum) >= 0;
+
+        if (mode === "never" && noNextLineToken && !hasNextLineComment) {
+            context.report(node, NEVER_MESSAGE, { identifier: node.name });
+        }
+
+        if (mode === "always" && (!noNextLineToken || hasNextLineComment)) {
+            context.report(node, ALWAYS_MESSAGE, { identifier: node.name });
+        }
+    }
+
+    //--------------------------------------------------------------------------
+    // Public
+    //--------------------------------------------------------------------------
+
+    return {
+        "VariableDeclaration": checkForBlankLine
+    };
+
+};