Update: shebang came to check BOM and \r\n

docs/rules/shebang.md

@@ -21,6 +21,18 @@ The following patterns are considered problems for files in `bin` field of `pack
 console.log("hello"); /*error This file needs shebang "#!/usr/bin/env node".*/
 ```
 
+```js
+#!/usr/bin/env node  /*error This file must not have Unicode BOM.*/
+console.log("hello");
+// If this file has Unicode BOM.
+```
+
+```js
+#!/usr/bin/env node  /*error This file must have Unix linebreaks (LF).*/
+console.log("hello");
+// If this file has Windows' linebreaks (CRLF).
+```
+
 The following patterns are considered problems for other files:
 
 ```js

lib/rules/shebang.js

@@ -19,7 +19,7 @@ var getPackageJson = require("../util/get-package-json");
 //------------------------------------------------------------------------------
 
 var NODE_SHEBANG = "#!/usr/bin/env node\n";
-var SHEBANG_PATTERN = /^#\!.+?\n/;
+var SHEBANG_PATTERN = /^(\uFEFF)?(#\!.+?)?(\r)?\n/;
 
 /**
  * Checks whether or not a given path is a `bin` file.
@@ -45,18 +45,30 @@ function isBinFile(filePath, binField, basedir) {
  * Gets the shebang line (includes a line ending) from a given code.
  *
  * @param {SourceCode} sourceCode - A source code object to check.
- * @returns {string} shebang if exists. Otherwise an empty string.
+ * @returns {{length: number, bom: boolean, shebang: string, cr: boolean}}
+ *      shebang's information.
+ *      `retv.shebang` is an empty string if shebang doesn't exist.
  */
-function getShebang(sourceCode) {
+function getShebangInfo(sourceCode) {
     var m = SHEBANG_PATTERN.exec(sourceCode.text);
-    return (m && m[0]) || "";
+
+    // ESLint v1 has BOM in text.
+    // ESLint v2 strips BOM from text, and has the "hasBOM" property.
+    return {
+        bomIndex: (typeof sourceCode.hasBOM === "boolean" ? -1 : 0),
+        bom: (typeof sourceCode.hasBOM === "boolean" ? sourceCode.hasBOM : Boolean(m && m[1])),
+        cr: Boolean(m && m[3]),
+        length: (m && m[0].length || (sourceCode.text.charCodeAt(0) === 0xFEFF ? 1 : 0)),
+        shebang: (m && (m[2] + "\n") || "")
+    };
 }
 
 //------------------------------------------------------------------------------
 // Rule Definition
 //------------------------------------------------------------------------------
 
 module.exports = function(context) {
+    var sourceCode = context.getSourceCode();
     var filePath = context.getFilename();
     if (filePath === "<input>") {
         return {};
@@ -75,36 +87,53 @@ module.exports = function(context) {
     );
 
     var needsShebang = isBinFile(filePath, p.bin, basedir);
-    var shebang = getShebang(context.getSourceCode());
-    if (needsShebang ? shebang === NODE_SHEBANG : !shebang) {
-        return {};
-    }
+    var info = getShebangInfo(sourceCode);
 
-    if (needsShebang) {
-        return {
-            Program: function(node) {
+    return {
+        Program: function(node) {
+            if (needsShebang ? info.shebang === NODE_SHEBANG : !info.shebang) {
+                // Good the shebang target.
+                // Checks BOM and \r.
+                if (needsShebang && info.bom) {
+                    context.report({
+                        node: node,
+                        message: "This file must not have Unicode BOM.",
+                        fix: function(fixer) {
+                            return fixer.removeRange([info.bomIndex, info.bomIndex + 1]);
+                        }
+                    });
+                }
+                if (needsShebang && info.cr) {
+                    context.report({
+                        node: node,
+                        message: "This file must have Unix linebreaks (LF).",
+                        fix: function(fixer) {
+                            var index = sourceCode.text.indexOf("\r");
+                            return fixer.removeRange([index, index + 1]);
+                        }
+                    });
+                }
+            }
+            else if (needsShebang) {
+                // Shebang is lacking.
                 context.report({
                     node: node,
                     message: "This file needs shebang \"#!/usr/bin/env node\".",
                     fix: function(fixer) {
-                        if (shebang) {
-                            return fixer.replaceTextRange([0, shebang.length], NODE_SHEBANG);
-                        }
-                        return fixer.insertTextBeforeRange([0, 0], NODE_SHEBANG);
+                        return fixer.replaceTextRange([info.bomIndex, info.length], NODE_SHEBANG);
+                    }
+                });
+            }
+            else {
+                // Shebang is extra.
+                context.report({
+                    node: node,
+                    message: "This file needs no shebang.",
+                    fix: function(fixer) {
+                        return fixer.removeRange([0, info.length]);
                     }
                 });
             }
-        };
-    }
-    return {
-        Program: function(node) {
-            context.report({
-                node: node,
-                message: "This file needs no shebang.",
-                fix: function(fixer) {
-                    return fixer.removeRange([0, shebang.length]);
-                }
-            });
         }
     };
 };

tests/lib/rules/shebang.js

@@ -101,6 +101,24 @@ ruleTester.run("shebang", rule, {
         {
             filename: "tests/fixtures/shebang/string-bin/lib/test.js",
             code: "hello();"
+        },
+
+        // BOM and \r\n
+        {
+            filename: fixture("string-bin/lib/test.js"),
+            code: "\uFEFFhello();"
+        },
+        {
+            filename: fixture("string-bin/lib/test.js"),
+            code: "\uFEFFhello();\n"
+        },
+        {
+            filename: fixture("string-bin/lib/test.js"),
+            code: "hello();\r\n"
+        },
+        {
+            filename: fixture("string-bin/lib/test.js"),
+            code: "\uFEFFhello();\r\n"
         }
     ],
     invalid: [
@@ -225,6 +243,61 @@ ruleTester.run("shebang", rule, {
             code: "/* header */\nhello();",
             output: "#!/usr/bin/env node\n/* header */\nhello();",
             errors: ["This file needs shebang \"#!/usr/bin/env node\"."]
+        },
+
+        // BOM and \r\n
+        {
+            filename: fixture("string-bin/bin/test.js"),
+            code: "\uFEFFhello();",
+            output: "#!/usr/bin/env node\nhello();",
+            errors: ["This file needs shebang \"#!/usr/bin/env node\"."]
+        },
+        {
+            filename: fixture("string-bin/bin/test.js"),
+            code: "hello();\n",
+            output: "#!/usr/bin/env node\nhello();\n",
+            errors: ["This file needs shebang \"#!/usr/bin/env node\"."]
+        },
+        {
+            filename: fixture("string-bin/bin/test.js"),
+            code: "hello();\r\n",
+            output: "#!/usr/bin/env node\nhello();\r\n",
+            errors: ["This file needs shebang \"#!/usr/bin/env node\"."]
+        },
+        {
+            filename: fixture("string-bin/bin/test.js"),
+            code: "\uFEFFhello();\n",
+            output: "#!/usr/bin/env node\nhello();\n",
+            errors: ["This file needs shebang \"#!/usr/bin/env node\"."]
+        },
+        {
+            filename: fixture("string-bin/bin/test.js"),
+            code: "\uFEFFhello();\r\n",
+            output: "#!/usr/bin/env node\nhello();\r\n",
+            errors: ["This file needs shebang \"#!/usr/bin/env node\"."]
+        // ESLint v1 does not support
+        // },
+        // {
+        //     filename: fixture("string-bin/bin/test.js"),
+        //     code: "\uFEFF#!/usr/bin/env node\nhello();",
+        //     output: "#!/usr/bin/env node\nhello();",
+        //     errors: ["This file must not have Unicode BOM."]
+        },
+        {
+            filename: fixture("string-bin/bin/test.js"),
+            code: "#!/usr/bin/env node\r\nhello();",
+            output: "#!/usr/bin/env node\nhello();",
+            errors: ["This file must have Unix linebreaks (LF)."]
+        // ESLint v1 does not support
+        // },
+        // {
+        //     filename: fixture("string-bin/bin/test.js"),
+        //     code: "\uFEFF#!/usr/bin/env node\r\nhello();",
+        //     output: "#!/usr/bin/env node\nhello();",
+        //     errors: [
+        //         "This file must not have Unicode BOM.",
+        //         "This file must have Unix linebreaks (LF)."
+        //     ]
         }
     ]
 });