feat($log): log all parameters in IE 9, not just the first two.

IE 9 lacks apply on console methods but it's possible to borrow the apply
method from Function.prototype.

Author: mgol

src/ng/log.js

@@ -146,29 +146,17 @@ function $LogProvider() {
 
     function consoleLog(type) {
       var console = $window.console || {},
-          logFn = console[type] || console.log || noop,
-          hasApply = false;
+          logFn = console[type] || console.log || noop;
 
-      // Note: reading logFn.apply throws an error in IE11 in IE8 document mode.
-      // The reason behind this is that console.log has type "object" in IE8...
-      try {
-        hasApply = !!logFn.apply;
-      } catch (e) { /* empty */ }
-
-      if (hasApply) {
-        return function() {
-          var args = [];
-          forEach(arguments, function(arg) {
-            args.push(formatError(arg));
-          });
-          return logFn.apply(console, args);
-        };
-      }
-
-      // we are IE which either doesn't have window.console => this is noop and we do nothing,
-      // or we are IE where console.log doesn't have apply so we log at least first 2 args
-      return function(arg1, arg2) {
-        logFn(arg1, arg2 == null ? '' : arg2);
+      return function() {
+        var args = [];
+        forEach(arguments, function(arg) {
+          args.push(formatError(arg));
+        });
+        // Support: IE 9 only
+        // console methods don't inherit from Function.prototype in IE 9 so we can't
+        // call `logFn.apply(console, args)` directly.
+        return Function.prototype.apply.call(logFn, console, args);
       };
     }
   }];

test/ng/logSpec.js

@@ -101,24 +101,29 @@ describe('$log', function() {
       })
     );
 
-    it('should not attempt to log the second argument in IE if it is not specified', inject(
-      function() {
-        log = function(arg1, arg2) { logger += 'log;' + arg2; };
-        warn = function(arg1, arg2) { logger += 'warn;' + arg2; };
-        info = function(arg1, arg2) { logger += 'info;' + arg2; };
-        error = function(arg1, arg2) { logger += 'error;' + arg2; };
-        debug = function(arg1, arg2) { logger += 'debug;' + arg2; };
-      },
-      removeApplyFunctionForIE,
-      function($log) {
-        $log.log();
-        $log.warn();
-        $log.info();
-        $log.error();
-        $log.debug();
-        expect(logger).toEqual('log;warn;info;error;debug;');
-      })
-    );
+    // Support: Safari 9.1 only, iOS 9.3 only
+    // For some reason Safari thinks there is always 1 parameter passed here.
+    if (!/\b9\.\d(\.\d+)* safari/i.test(window.navigator.userAgent) &&
+      !/\biphone os 9_/i.test(window.navigator.userAgent)) {
+      it('should not attempt to log the second argument in IE if it is not specified', inject(
+        function() {
+          log = function(arg1, arg2) { logger += 'log,' + arguments.length + ';'; };
+          warn = function(arg1, arg2) { logger += 'warn,' + arguments.length + ';'; };
+          info = function(arg1, arg2) { logger += 'info,' + arguments.length + ';'; };
+          error = function(arg1, arg2) { logger += 'error,' + arguments.length + ';'; };
+          debug = function(arg1, arg2) { logger += 'debug,' + arguments.length + ';'; };
+        },
+        removeApplyFunctionForIE,
+        function($log) {
+          $log.log();
+          $log.warn();
+          $log.info();
+          $log.error();
+          $log.debug();
+          expect(logger).toEqual('log,0;warn,0;info,0;error,0;debug,0;');
+        })
+      );
+    }
   });
 
   describe('$log.debug', function() {