Create a top-level "third_party" directory

This directory now contains third_party software that is vendored into
the Servo source tree. The idea is that it would eventually hold
webrender and other crates from mozilla-central as well with a standard
patch management approach for each.

third_party/WebIDL/tests/test_stringifier.py

@@ -0,0 +1,196 @@
+import WebIDL
+
+
+def WebIDLTest(parser, harness):
+    parser.parse(
+        """
+        interface TestStringifier {
+          stringifier;
+        };
+    """
+    )
+
+    results = parser.finish()
+
+    harness.ok(
+        isinstance(results[0].members[0], WebIDL.IDLMethod),
+        "Stringifer should be method",
+    )
+
+    parser = parser.reset()
+
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestStringifier {
+              stringifier;
+              stringifier;
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "Should not allow two 'stringifier;'")
+
+    parser = parser.reset()
+
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestStringifier {
+              stringifier;
+              stringifier DOMString foo();
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "Should not allow a 'stringifier;' and a 'stringifier()'")
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestStringifier {
+            stringifier attribute DOMString foo;
+        };
+    """
+    )
+    results = parser.finish()
+    harness.ok(
+        isinstance(results[0].members[0], WebIDL.IDLAttribute),
+        "Stringifier attribute should be an attribute",
+    )
+    stringifier = results[0].members[1]
+    harness.ok(
+        isinstance(stringifier, WebIDL.IDLMethod),
+        "Stringifier attribute should insert a method",
+    )
+    harness.ok(stringifier.isStringifier(), "Inserted method should be a stringifier")
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestStringifier {};
+        interface mixin TestStringifierMixin {
+            stringifier attribute DOMString foo;
+        };
+        TestStringifier includes TestStringifierMixin;
+    """
+    )
+    results = parser.finish()
+    harness.ok(
+        isinstance(results[0].members[0], WebIDL.IDLAttribute),
+        "Stringifier attribute should be an attribute",
+    )
+    stringifier = results[0].members[1]
+    harness.ok(
+        isinstance(stringifier, WebIDL.IDLMethod),
+        "Stringifier attribute should insert a method",
+    )
+    harness.ok(stringifier.isStringifier(), "Inserted method should be a stringifier")
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestStringifier {
+            stringifier attribute USVString foo;
+        };
+    """
+    )
+    results = parser.finish()
+    stringifier = results[0].members[1]
+    harness.ok(
+        stringifier.signatures()[0][0].isUSVString(),
+        "Stringifier attributes should allow USVString",
+    )
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestStringifier {
+            [Throws, NeedsSubjectPrincipal]
+            stringifier attribute USVString foo;
+        };
+    """
+    )
+    results = parser.finish()
+    stringifier = results[0].members[1]
+    harness.ok(
+        stringifier.getExtendedAttribute("Throws"),
+        "Stringifier attributes should support [Throws]",
+    )
+    harness.ok(
+        stringifier.getExtendedAttribute("NeedsSubjectPrincipal"),
+        "Stringifier attributes should support [NeedsSubjectPrincipal]",
+    )
+
+    parser = parser.reset()
+    parser.parse(
+        """
+        interface TestStringifier {
+            stringifier attribute UTF8String foo;
+        };
+    """
+    )
+    results = parser.finish()
+    stringifier = results[0].members[1]
+    harness.ok(
+        stringifier.signatures()[0][0].isUTF8String(),
+        "Stringifier attributes should allow UTF8String",
+    )
+
+    parser = parser.reset()
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestStringifier {
+              stringifier attribute ByteString foo;
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "Should not allow ByteString")
+
+    parser = parser.reset()
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestStringifier {
+              stringifier;
+              stringifier attribute DOMString foo;
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "Should not allow a 'stringifier;' and a stringifier attribute")
+
+    parser = parser.reset()
+    threw = False
+    try:
+        parser.parse(
+            """
+            interface TestStringifier {
+              stringifier attribute DOMString foo;
+              stringifier attribute DOMString bar;
+            };
+        """
+        )
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "Should not allow multiple stringifier attributes")