Auto merge of #7447 - ddrmanxbxfr:master, r=jdm

Issue #7382 Use descriptive enums instead of booleans for MIMEClassifier::classifer

Hi guys i've done a small pass of refactor in the MIMEClassifier implementation. (See issue #7382 )
   - Moved the predicates to separate functions
   - Added a mimetype enum so we can compare them easily after calling MIMEClassifier::get_media_type

I hope it follows rust good pratices (care it's my first time doing rust).

Improvements and tips are welcome :).

Thanks for looking at it.

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tests/unit/net/mime_classifier.rs

@@ -3,7 +3,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 use net::mime_classifier::as_string_option;
-use net::mime_classifier::{Mp4Matcher, MIMEClassifier};
+use net::mime_classifier::{Mp4Matcher, MIMEClassifier, ApacheBugFlag, NoSniffFlag};
 use std::env;
 use std::fs::File;
 use std::io::{self, Read};
@@ -37,8 +37,12 @@ fn test_sniff_mp4_matcher() {
 }
 
 #[cfg(test)]
-fn test_sniff_full(filename_orig: &path::Path, type_string: &str, subtype_string: &str,
-                   supplied_type: Option<(&'static str, &'static str)>) {
+fn test_sniff_with_flags(filename_orig: &path::Path,
+                                 type_string: &str,
+                                 subtype_string: &str,
+                                 supplied_type: Option<(&'static str, &'static str)>,
+                                 no_sniff_flag: NoSniffFlag,
+                                 apache_bug_flag: ApacheBugFlag) {
     let current_working_directory = env::current_dir().unwrap();
     println!("The current directory is {}", current_working_directory.display());
 
@@ -51,7 +55,7 @@ fn test_sniff_full(filename_orig: &path::Path, type_string: &str, subtype_string
 
     match read_result {
         Ok(data) => {
-            match classifier.classify(false, false, &as_string_option(supplied_type), &data) {
+            match classifier.classify(no_sniff_flag, apache_bug_flag, &as_string_option(supplied_type), &data) {
                 Some((parsed_type, parsed_subtp)) => {
                     if (&parsed_type[..] != type_string) ||
                         (&parsed_subtp[..] != subtype_string) {
@@ -69,6 +73,17 @@ fn test_sniff_full(filename_orig: &path::Path, type_string: &str, subtype_string
     }
 }
 
+#[cfg(test)]
+fn test_sniff_full(filename_orig: &path::Path, type_string: &str, subtype_string: &str,
+                   supplied_type: Option<(&'static str, &'static str)>) {
+    test_sniff_with_flags(filename_orig,
+                          type_string,
+                          subtype_string,
+                          supplied_type,
+                          NoSniffFlag::OFF,
+                          ApacheBugFlag::OFF)
+}
+
 #[cfg(test)]
 fn test_sniff_classification(file: &str, type_string: &str, subtype_string: &str,
                              supplied_type: Option<(&'static str, &'static str)>) {
@@ -448,3 +463,79 @@ fn test_sniff_rss_feed() {
 fn test_sniff_atom_feed() {
     test_sniff_full(&PathBuf::from("text/xml/feed.atom"), "application", "atom+xml", Some(("text", "html")));
 }
+
+#[test]
+fn test_sniff_binary_file() {
+    test_sniff_full(&PathBuf::from("unknown/binary_file"), "application", "octet-stream", None);
+}
+
+#[test]
+fn test_sniff_atom_feed_with_no_sniff_flag_on() {
+    test_sniff_with_flags(&PathBuf::from("text/xml/feed.atom"),
+                                  "text",
+                                  "html",
+                                  Some(("text", "html")),
+                                  NoSniffFlag::ON,
+                                  ApacheBugFlag::OFF);
+}
+
+#[test]
+fn test_sniff_with_no_sniff_flag_on_and_apache_flag_on() {
+    test_sniff_with_flags(&PathBuf::from("text/xml/feed.atom"),
+                                  "text",
+                                  "html",
+                                  Some(("text", "html")),
+                                  NoSniffFlag::ON,
+                                  ApacheBugFlag::ON);
+}
+
+#[test]
+fn test_sniff_utf_8_bom_with_apache_flag_on() {
+    test_sniff_with_flags(&PathBuf::from("text/plain/utf8bom.txt"),
+                                  "text",
+                                  "plain",
+                                  Some(("dummy", "text")),
+                                  NoSniffFlag::OFF,
+                                  ApacheBugFlag::ON);
+}
+
+#[test]
+fn test_sniff_utf_16be_bom_with_apache_flag_on() {
+    test_sniff_with_flags(&PathBuf::from("text/plain/utf16bebom.txt"),
+                                  "text",
+                                  "plain",
+                                  Some(("dummy", "text")),
+                                  NoSniffFlag::OFF,
+                                  ApacheBugFlag::ON);
+}
+
+#[test]
+fn test_sniff_utf_16le_bom_with_apache_flag_on() {
+    test_sniff_with_flags(&PathBuf::from("text/plain/utf16lebom.txt"),
+                                  "text",
+                                  "plain",
+                                  Some(("dummy", "text")),
+                                  NoSniffFlag::OFF,
+                                  ApacheBugFlag::ON);
+}
+
+#[test]
+fn test_sniff_octet_stream_apache_flag_on() {
+    test_sniff_with_flags(&PathBuf::from("unknown/binary_file"),
+                                  "application",
+                                  "octet-stream",
+                                  Some(("dummy", "binary")),
+                                  NoSniffFlag::OFF,
+                                  ApacheBugFlag::ON);
+}
+
+#[test]
+fn test_sniff_mp4_video_apache_flag_on() {
+    test_sniff_with_flags(&PathBuf::from("video/mp4/test.mp4"),
+                          "application",
+                          "octet-stream",
+                          Some(("video", "mp4")),
+                          NoSniffFlag::OFF,
+                          ApacheBugFlag::ON);
+}
+