#10071 bash detection for extensionless file

src/document/Document.js

@@ -77,7 +77,7 @@ define(function (require, exports, module) {
      */
     function Document(file, initialTimestamp, rawText) {
         this.file = file;
-        this._updateLanguage();
+        this._updateLanguage(rawText);
         this.refreshText(rawText, initialTimestamp, true);
     }
 
@@ -675,10 +675,15 @@ define(function (require, exports, module) {
 
     /**
      * Updates the language to match the current mapping given by LanguageManager
+     * 
+     * @param {!string} rawText  Text content of the file.
      */
-    Document.prototype._updateLanguage = function () {
+    Document.prototype._updateLanguage = function (rawText) {
         var oldLanguage = this.language;
         this.language = LanguageManager.getLanguageForPath(this.file.fullPath);
+        if (this.language === LanguageManager.getLanguage("unknown")) {
+            this.language = LanguageManager.getLanguageForContent(rawText);
+        }
         if (oldLanguage && oldLanguage !== this.language) {
             this.trigger("languageChanged", oldLanguage, this.language);
         }

src/language/LanguageManager.js

@@ -243,6 +243,28 @@ define(function (require, exports, module) {
     function getLanguage(id) {
         return _languages[id];
     }
+
+    /**
+     * Resolves a file content to a Language object.
+     * @param {!string} rawText  Text content of the file.
+     *
+     * @return {Language} The language detected based on file content or the fallback language
+     */
+    function getLanguageForContent(rawText) {
+        // Shebang detection for script languages 
+        if (rawText) {
+            //filter out #!/usr/bin/, #!/usr/local/bin/, #!/bin/, #!/usr/bin/env, and arguments in order to get language name
+            //for python, it filters out version number as well (python2 python3 -> python) 
+            var lang = rawText.match(/^#!(?:\/usr\/bin\/env\ |(?:\/usr|\/usr\/local)?\/bin\/)(python(?=[23]\W)|(?!python)\w+)[^\r\n]*[\r\n]/m);
+            if (lang && lang[1] && _languages[lang[1]]) {
+                return _languages[lang[1]];
+            }
+            else if (lang && lang[1] && _languages[lang[1]] === "sh") { //workaround for bash
+                return _languages.bash;
+            }
+        }
+        return _fallbackLanguage;
+    }
 
     /**
      * Resolves a file extension to a Language object.
@@ -461,7 +483,7 @@ define(function (require, exports, module) {
      * @type {{ prefix: string, suffix: string }}
      */
     Language.prototype._blockCommentSyntax = null;
-    
+
     /**
      * Whether or not the language is binary
      * @type {boolean}
@@ -803,7 +825,7 @@ define(function (require, exports, module) {
 
         return true;
     };
-    
+
     /**
      * Returns either a language associated with the mode or the fallback language.
      * Used to disambiguate modes used by multiple languages.
@@ -863,7 +885,7 @@ define(function (require, exports, module) {
     Language.prototype.isBinary = function () {
         return this._isBinary;
     };
-    
+
     /**
      * Sets whether or not the language is binary
      * @param {!boolean} isBinary
@@ -922,7 +944,7 @@ define(function (require, exports, module) {
             }
 
             language._setBinary(!!definition.isBinary);
-            
+
             // store language to language map
             _languages[language.getId()] = language;
         }
@@ -1128,6 +1150,7 @@ define(function (require, exports, module) {
     exports.getLanguage                 = getLanguage;
     exports.getLanguageForExtension     = getLanguageForExtension;
     exports.getLanguageForPath          = getLanguageForPath;
+    exports.getLanguageForContent       = getLanguageForContent;
     exports.getLanguages                = getLanguages;
     exports.setLanguageOverrideForPath  = setLanguageOverrideForPath;
 });

test/spec/LanguageManager-test.js

@@ -270,6 +270,37 @@ define(function (require, exports, module) {
             });
         });
 
+        describe("auto detection for extensionless file", function () {
+
+            it("should return appropriate language", function () {
+                var text    = "#!/bin/sh\n\necho 123";
+                var text2   = "#!/bin/bash\n\necho 123";
+                var text3   = "#!/usr/bin/env bash\n\necho 123";
+                var text4   = "123\n\necho 123";
+                var text5   = "#!/bin/shell\n\necho 123";
+                var text6   = "#!/usr/bin/python2\n\nprint 'hello world'";
+                var text7   = "#!/usr/bin/python3\n\nprint 'hello world'";
+                var text8   = "#!/usr/bin/python222\n\nprint 'hello world'";
+                var text9   = "#!/usr/bin/python -c\n\nprint 'hello world'";
+
+                var bash    = LanguageManager.getLanguage("bash"),
+                    python    = LanguageManager.getLanguage("python"),
+                    unknown = LanguageManager.getLanguage("unknown");
+
+                expect(LanguageManager.getLanguageForContent(text)).toBe(bash);
+                expect(LanguageManager.getLanguageForContent(text2)).toBe(bash);
+                expect(LanguageManager.getLanguageForContent(text3)).toBe(bash);
+                expect(LanguageManager.getLanguageForContent(text4)).toBe(unknown);
+                expect(LanguageManager.getLanguageForContent(text5)).toBe(unknown);
+                expect(LanguageManager.getLanguageForContent(text6)).toBe(python);
+                expect(LanguageManager.getLanguageForContent(text7)).toBe(python);
+                expect(LanguageManager.getLanguageForContent(text8)).toBe(unknown);
+                expect(LanguageManager.getLanguageForContent(text9)).toBe(python);
+
+            });
+
+        });
+
         describe("defineLanguage", function () {
 
             it("should create a basic language", function () {