Parse webidl files and lint for inheritance correctness.

Cargo.lock

@@ -117,6 +117,14 @@ name = "ascii"
 version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "ascii-canvas"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "term 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "atomic_refcell"
 version = "0.1.0"
@@ -237,6 +245,19 @@ dependencies = [
  "which 2.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "bit-set"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "bit-vec 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "bit-vec"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "bitflags"
 version = "1.0.3"
@@ -1010,6 +1031,11 @@ dependencies = [
  "time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "diff"
+version = "0.1.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "digest"
 version = "0.7.6"
@@ -1043,6 +1069,18 @@ dependencies = [
  "libloading 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "docopt"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
+ "strsim 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "dom_struct"
 version = "0.0.1"
@@ -1113,6 +1151,14 @@ dependencies = [
  "webrender_api 0.60.0 (git+https://github.com/servo/webrender)",
 ]
 
+[[package]]
+name = "ena"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "encoding_rs"
 version = "0.8.12"
@@ -2190,6 +2236,35 @@ name = "khronos_api"
 version = "3.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "lalrpop"
+version = "0.16.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "ascii-canvas 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bit-set 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)",
+ "docopt 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ena 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itertools 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lalrpop-util 0.16.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "petgraph 0.4.13 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex-syntax 0.6.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.80 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sha2 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "string_cache 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "term 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "unicode-xid 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "lalrpop-util"
+version = "0.16.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "layout"
 version = "0.0.1"
@@ -3592,6 +3667,9 @@ dependencies = [
 [[package]]
 name = "script_plugins"
 version = "0.0.1"
+dependencies = [
+ "webidl 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "script_plugins_tests"
@@ -4217,6 +4295,11 @@ name = "strsim"
 version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "strsim"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
 [[package]]
 name = "style"
 version = "0.0.1"
@@ -4389,6 +4472,15 @@ dependencies = [
  "utf-8 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "term"
+version = "0.4.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "termcolor"
 version = "1.0.4"
@@ -4944,6 +5036,15 @@ dependencies = [
  "webdriver 0.39.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "webidl"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "lalrpop 0.16.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lalrpop-util 0.16.3 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "webrender"
 version = "0.60.0"
@@ -5253,6 +5354,7 @@ dependencies = [
 "checksum arrayref 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "0d382e583f07208808f6b1249e60848879ba3543f57c32277bf52d69c2f0f0ee"
 "checksum arrayvec 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "2f0ef4a9820019a0c91d918918c93dc71d469f581a49b47ddc1d285d4270bbe2"
 "checksum ascii 0.7.1 (registry+https://github.com/rust-lang/crates.io-index)" = "3ae7d751998c189c1d4468cf0a39bb2eae052a9c58d50ebb3b9591ee3813ad50"
+"checksum ascii-canvas 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b385d69402821a1c254533a011a312531cbcc0e3e24f19bbb4747a5a2daf37e2"
 "checksum atomic_refcell 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fb2dcb6e6d35f20276943cc04bb98e538b348d525a04ac79c10021561d202f21"
 "checksum atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "9a7d5b8723950951411ee34d271d99dddcc2035a16ab25310ea2c8cfd4369652"
 "checksum azure 0.35.0 (git+https://github.com/servo/rust-azure)" = "<none>"
@@ -5263,6 +5365,8 @@ dependencies = [
 "checksum binary-space-partition 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "88ceb0d16c4fd0e42876e298d7d3ce3780dd9ebdcbe4199816a32c77e08597ff"
 "checksum bincode 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bda13183df33055cbb84b847becce220d392df502ebe7a4a78d7021771ed94d0"
 "checksum bindgen 0.49.0 (registry+https://github.com/rust-lang/crates.io-index)" = "33e1b67a27bca31fd12a683b2a3618e275311117f48cfcc892e18403ff889026"
+"checksum bit-set 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "e84c238982c4b1e1ee668d136c510c67a13465279c0cb367ea6baf6310620a80"
+"checksum bit-vec 0.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "f59bbe95d4e52a6398ec21238d31577f2b28a9d86807f06ca59d191d8440d0bb"
 "checksum bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "d0c54bb8f454c567f21197eefcdbf5679d0bd99f2ddbe52e84c77061952e6789"
 "checksum block 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "0d8c1fef690941d3e7788d328517591fecc684c084084702d6ff1641e993699a"
 "checksum block-buffer 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "a076c298b9ecdb530ed9d967e74a6027d6a7478924520acddcddc24c1c8ab3ab"
@@ -5326,15 +5430,18 @@ dependencies = [
 "checksum deflate 0.7.19 (registry+https://github.com/rust-lang/crates.io-index)" = "8a6abb26e16e8d419b5c78662aa9f82857c2386a073da266840e474d5055ec86"
 "checksum derive_more 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3f57d78cf3bd45270dad4e70c21ec77a960b36c7a841ff9db76aaa775a8fb871"
 "checksum device 0.0.1 (git+https://github.com/servo/devices)" = "<none>"
+"checksum diff 0.1.11 (registry+https://github.com/rust-lang/crates.io-index)" = "3c2b69f912779fbb121ceb775d74d51e915af17aaebc38d28a592843a2dd0a3a"
 "checksum digest 0.7.6 (registry+https://github.com/rust-lang/crates.io-index)" = "03b072242a8cbaf9c145665af9d250c59af3b958f83ed6824e13533cf76d5b90"
 "checksum digest 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "05f47366984d3ad862010e22c7ce81a7dbcaebbdfb37241a620f8b6596ee135c"
 "checksum dirs 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "37a76dd8b997af7107d0bb69d43903cf37153a18266f8b3fdb9911f28efb5444"
 "checksum dlib 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "77e51249a9d823a4cb79e3eca6dcd756153e8ed0157b6c04775d04bf1b13b76a"
+"checksum docopt 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "db2906c2579b5b7207fc1e328796a9a8835dc44e22dbe8e460b1d636f9a7b225"
 "checksum downcast-rs 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "18df8ce4470c189d18aa926022da57544f31e154631eb4cfe796aea97051fe6c"
 "checksum dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "80c8b71fd71146990a9742fc06dcbbde19161a267e0ad4e572c35162f4578c90"
 "checksum dtoa-short 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fe6f727b406462fd57c95fed84d1b0dbfb5f0136fcac005adba9ea0367c05cc8"
 "checksum dwrote 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c31c624339dab99c223a4b26c2e803b7c248adaca91549ce654c76f39a03f5c8"
 "checksum either 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "18785c1ba806c258137c937e44ada9ee7e69a37e3c72077542cd2f069d78562a"
+"checksum ena 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f56c93cc076508c549d9bb747f79aa9b4eb098be7b8cad8830c3137ef52d1e00"
 "checksum encoding_rs 0.8.12 (registry+https://github.com/rust-lang/crates.io-index)" = "ca20350a7cb5aab5b9034731123d6d412caf3e92d4985e739e411ba0955fd0eb"
 "checksum energy-monitor 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "fe872d0664f1cc60db36349af245d892ee67d3c8f78055df0ebc43271fd4e05c"
 "checksum energymon 0.3.0 (git+https://github.com/energymon/energymon-rust.git)" = "<none>"
@@ -5432,6 +5539,8 @@ dependencies = [
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum keyboard-types 0.4.4 (registry+https://github.com/rust-lang/crates.io-index)" = "53b536dc22c0dabb295e85dbd0c062023885b12b8db24e1d86833f4e50ea7959"
 "checksum khronos_api 3.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "62237e6d326bd5871cd21469323bf096de81f1618cd82cbaf5d87825335aeb49"
+"checksum lalrpop 0.16.3 (registry+https://github.com/rust-lang/crates.io-index)" = "4e2e80bee40b22bca46665b4ef1f3cd88ed0fb043c971407eac17a0712c02572"
+"checksum lalrpop-util 0.16.3 (registry+https://github.com/rust-lang/crates.io-index)" = "33b27d8490dbe1f9704b0088d61e8d46edc10d5673a8829836c6ded26a9912c7"
 "checksum lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a374c89b9db55895453a74c1e38861d9deec0b01b405a82516e9d5de4820dea1"
 "checksum lazycell 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d33a48d0365c96081958cc663eef834975cb1e8d8bea3378513fc72bdbf11e50"
 "checksum leak 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "bd100e01f1154f2908dfa7d02219aeab25d0b9c7fa955164192e3245255a0c73"
@@ -5576,11 +5685,13 @@ dependencies = [
 "checksum string_cache_codegen 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1eea1eee654ef80933142157fdad9dd8bc43cf7c74e999e369263496f04ff4da"
 "checksum string_cache_shared 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b1884d1bc09741d466d9b14e6d37ac89d6909cbcac41dd9ae982d4d063bbedfc"
 "checksum strsim 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b4d15c810519a91cf877e7e36e63fe068815c678181439f2f29e2562147c3694"
+"checksum strsim 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bb4f380125926a99e52bc279241539c018323fab05ad6368b56f93d9369ff550"
 "checksum swapper 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "e454d048db5527d000bfddb77bd072bbf3a1e2ae785f16d9bd116e07c2ab45eb"
 "checksum syn 0.15.22 (registry+https://github.com/rust-lang/crates.io-index)" = "ae8b29eb5210bc5cf63ed6149cbf9adfc82ac0be023d8735c176ee74a2db4da7"
 "checksum synstructure 0.10.1 (registry+https://github.com/rust-lang/crates.io-index)" = "73687139bf99285483c96ac0add482c3776528beac1d97d444f6e91f203a2015"
 "checksum tempfile 3.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "47776f63b85777d984a50ce49d6b9e58826b6a3766a449fc95bc66cd5663c15b"
 "checksum tendril 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "707feda9f2582d5d680d733e38755547a3e8fb471e7ba11452ecfd9ce93a5d3b"
+"checksum term 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "fa63644f74ce96fbeb9b794f66aff2a52d601cbd5e80f4b97123e3899f4570f1"
 "checksum termcolor 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "4096add70612622289f2fdcdbd5086dc81c1e2675e6ae58d6c4f62a16c6d7f2f"
 "checksum termion 1.5.1 (registry+https://github.com/rust-lang/crates.io-index)" = "689a3bdfaab439fd92bc87df5c4c78417d3cbe537487274e9b0b2dce76e92096"
 "checksum textwrap 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c0b59b6b4b44d867f1370ef1bd91bfb262bf07bf0ae65c202ea2fbc16153b693"
@@ -5638,6 +5749,7 @@ dependencies = [
 "checksum wayland-scanner 0.21.4 (registry+https://github.com/rust-lang/crates.io-index)" = "f1927ee62e4e149c010dc9eca8ca47e238416cd6f45f688eb9f8a8e9c3794c30"
 "checksum wayland-sys 0.21.4 (registry+https://github.com/rust-lang/crates.io-index)" = "ca41ed78a12256f81df6f53fcbe4503213ba442e02cdad3c9c888a64a668eaf4"
 "checksum webdriver 0.39.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0533b0b0a05e2e5c081317759a038482806c6085c9605dded03c8bbd2498b042"
+"checksum webidl 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d0f807f7488d680893f7188aa09d7672a3a0a8461975a098a2edf0a52e3fee29"
 "checksum webrender 0.60.0 (git+https://github.com/servo/webrender)" = "<none>"
 "checksum webrender_api 0.60.0 (git+https://github.com/servo/webrender)" = "<none>"
 "checksum webrender_build 0.0.1 (git+https://github.com/servo/webrender)" = "<none>"

components/script_plugins/Cargo.toml

@@ -12,3 +12,6 @@ plugin = true
 [features]
 unrooted_must_root_lint = []
 webidl_lint = []
+
+[dependencies]
+webidl = "0.8"

components/script_plugins/lib.rs

@@ -25,6 +25,8 @@ extern crate rustc;
 extern crate rustc_plugin;
 extern crate syntax;
 
+extern crate webidl;
+
 use rustc_plugin::Registry;
 use syntax::feature_gate::AttributeType::Whitelisted;
 

components/script_plugins/webidl_must_inherit.rs

@@ -5,11 +5,18 @@
 use rustc::hir::{self, HirId};
 use rustc::lint::{LateContext, LateLintPass, LintArray, LintContext, LintPass};
 use rustc::ty;
+use std::boxed;
 use std::env;
-
+use std::error::Error;
+use std::fmt;
+use std::fs;
 use std::io;
 use std::path;
 use syntax::ast;
+use webidl::ast::*;
+use webidl::visitor::*;
+use webidl::*;
+
 declare_lint!(
     WEBIDL_INHERIT_CORRECT,
     Deny,
@@ -18,17 +25,52 @@ declare_lint!(
 
 pub struct WebIdlPass;
 
+#[derive(Clone, Debug)]
+pub enum WebIdlError {
+    ParentMismatch {
+        name: String,
+        rust_parent: String,
+        webidl_parent: String,
+    },
+}
+
+impl fmt::Display for WebIdlError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            WebIdlError::ParentMismatch {
+                name,
+                rust_parent,
+                webidl_parent,
+            } => {
+                return write!(f, "webidl-rust inheritance mismatch, rust: {:?}, rust parent: {:?}, webidl parent: {:?}",
+                    &name, &rust_parent, &webidl_parent);
+            },
+        }
+    }
+}
+
+impl Error for WebIdlError {
+    fn description(&self) -> &str {
+        "WebIdlError"
+    }
+
+    fn cause(&self) -> Option<&Error> {
+        None
+    }
+}
+
 impl WebIdlPass {
     pub fn new() -> WebIdlPass {
         WebIdlPass
     }
 }
 
-fn get_typ_name(typ: String) -> Option<String> {
+fn get_typ_name(typ: String) -> String {
     if let Some(i) = typ.rfind(':') {
-        return Some(typ[i + 1..].to_string());
+        typ[i + 1..].to_string()
+    } else {
+        typ
     }
-    None
 }
 
 fn get_webidl_path(struct_name: &str) -> io::Result<path::PathBuf> {
@@ -39,7 +81,6 @@ fn get_webidl_path(struct_name: &str) -> io::Result<path::PathBuf> {
     return Ok(dir);
 }
 
-/// Checks if a type is unrooted or contains any owned unrooted types
 fn is_webidl_ty(cx: &LateContext, ty: &ty::TyS) -> bool {
     let mut ret = false;
     ty.maybe_walk(|t| {
@@ -59,13 +100,31 @@ fn is_webidl_ty(cx: &LateContext, ty: &ty::TyS) -> bool {
     ret
 }
 
-fn check_webidl(name: &str, parent_name: Option<String>) -> io::Result<()> {
+fn check_inherits(code: &str, name: &str, parent_name: &str) -> Result<(), Box<Error>> {
+    let idl = parse_string(code)?;
+    let mut visitor = InterfaceVisitor::new(name.to_string());
+    visitor.visit(&idl);
+    let inherits = visitor.get_inherits();
+
+    println!("inherits: {:?}, parent_name: {:?}", inherits, parent_name);
+
+    if inherits == parent_name {
+        return Ok(());
+    }
+    Err(boxed::Box::from(WebIdlError::ParentMismatch {
+        name: name.to_string(),
+        rust_parent: parent_name.to_string(),
+        webidl_parent: inherits.to_string(),
+    }))
+}
+
+fn check_webidl(name: &str, parent_name: Option<String>) -> Result<(), Box<Error>> {
     let path = get_webidl_path(&name)?;
     println!("struct_webidl_path: {:?}", &path);
 
     if let Some(parent) = parent_name {
-        let parent_path = get_webidl_path(&parent)?;
+        let code = fs::read_to_string(path)?;
-        println!("parent_path: {:?}", &parent_path);
+        return check_inherits(&code, &name, &parent);
     }
 
     Ok(())
@@ -110,24 +169,55 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for WebIdlPass {
         for ref field in def.fields() {
             let def_id = cx.tcx.hir().local_def_id_from_hir_id(field.hir_id);
             let ty = cx.tcx.type_of(def_id);
-            let typ = ty.to_string();
+            let typ_name = get_typ_name(ty.to_string());
-            if let Some(typ_name) = get_typ_name(ty.to_string()) {
+            parent_typ_name = Some(typ_name);
-                parent_typ_name = Some(typ_name);
-                break;
-            } else {
-                cx.span_lint(WEBIDL_INHERIT_CORRECT, field.span, "Cannot get type name");
-            }
 
             // Only first field is relevant.
             break;
         }
 
-        // TODO Open and parse corresponding webidl file.
-        cx.span_lint(WEBIDL_INHERIT_CORRECT, item.ident.span, "WEBIDL present.");
-
         match check_webidl(&struct_name, parent_typ_name) {
             Ok(()) => {},
-            Err(e) => println!("ERRORRR: {:?}", e),
+            Err(e) => {
+                let description = format!("{}", e);
+                cx.span_lint(WEBIDL_INHERIT_CORRECT, item.ident.span, &description)
+            },
         };
     }
 }
+
+struct InterfaceVisitor {
+    name: String,
+    inherits: String,
+}
+
+impl InterfaceVisitor {
+    pub fn new(name: String) -> Self {
+        InterfaceVisitor {
+            name: name,
+            inherits: String::new(),
+        }
+    }
+
+    pub fn get_inherits(&self) -> &String {
+        &self.inherits
+    }
+}
+
+impl<'ast> ImmutableVisitor<'ast> for InterfaceVisitor {
+    fn visit_callback_interface(&mut self, callback_interface: &'ast CallbackInterface) {
+        if callback_interface.name == self.name {
+            if let Some(ref inherit) = callback_interface.inherits {
+                self.inherits = inherit.to_string()
+            }
+        }
+    }
+
+    fn visit_non_partial_interface(&mut self, non_partial_interface: &'ast NonPartialInterface) {
+        if non_partial_interface.name == self.name {
+            if let Some(ref inherit) = non_partial_interface.inherits {
+                self.inherits = inherit.to_string()
+            }
+        }
+    }
+}