Auto merge of #23200 - krk:webidl-lint, r=jdm

Webidl lint

Parse webidl files and lint for inheritance correctness.

---

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #20461

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---
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Cargo.lock

@@ -66,8 +66,11 @@ dependencies = [
 
 [[package]]
 name = "ansi_term"
-version = "0.10.2"
+version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
 
 [[package]]
 name = "antidote"
@@ -117,6 +120,14 @@ 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"
@@ -224,7 +235,7 @@ dependencies = [
  "cexpr 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "cfg-if 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "clang-sys 0.28.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "clap 2.28.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "clap 2.32.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "env_logger 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "hashbrown 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "lazy_static 1.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -237,6 +248,19 @@ 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"
@@ -464,7 +488,7 @@ name = "cbindgen"
 version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "clap 2.28.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "clap 2.32.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.4.6 (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)",
@@ -528,14 +552,14 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "2.28.0"
+version = "2.32.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "ansi_term 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "bitflags 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "strsim 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "strsim 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "textwrap 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "textwrap 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "unicode-width 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "vec_map 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -1010,6 +1034,11 @@ 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 +1072,18 @@ 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 +1154,14 @@ 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 +2239,35 @@ 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"
@@ -3593,6 +3671,9 @@ 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"
@@ -4232,7 +4313,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "strsim"
-version = "0.6.0"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -4407,6 +4488,15 @@ 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"
@@ -4427,7 +4517,7 @@ dependencies = [
 
 [[package]]
 name = "textwrap"
-version = "0.9.0"
+version = "0.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "unicode-width 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -4962,6 +5052,15 @@ 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"
@@ -5263,7 +5362,7 @@ dependencies = [
 "checksum android_injected_glue 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "80b9e34fcbf29c0563547cb2ecce9b49504597cad6166769b1e4efb45c6c2951"
 "checksum android_log-sys 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "b8052e2d8aabbb8d556d6abbcce2a22b9590996c5f849b9c7ce4544a2e3b984e"
 "checksum android_logger 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "cf44378e81264148f08e58336674542f82d0021f685d0be0320c82e1653dbe0b"
-"checksum ansi_term 0.10.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6b3568b48b7cefa6b8ce125f9bb4989e52fbcc29ebea88df04cc7c5f12f70455"
+"checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
 "checksum antidote 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "34fde25430d87a9388dadbe6e34d7f72a462c8b43ac8d309b42b0a8505d7e2a5"
 "checksum app_units 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9dadc668390b373e73e4abbfc1f07238b09a25858f2f39c06cebc6d8e141d774"
 "checksum approx 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "f71f10b5c4946a64aad7b8cf65e3406cd3da22fc448595991d22423cf6db67b4"
@@ -5271,6 +5370,7 @@ 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>"
@@ -5281,6 +5381,8 @@ 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"
@@ -5310,7 +5412,7 @@ dependencies = [
 "checksum cgl 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "55e7ec0b74fe5897894cbc207092c577e87c52f8a59e8ca8d97ef37551f60a49"
 "checksum chrono 0.4.2 (registry+https://github.com/rust-lang/crates.io-index)" = "1cce36c92cb605414e9b824f866f5babe0a0368e39ea07393b9b63cf3844c0e6"
 "checksum clang-sys 0.28.0 (registry+https://github.com/rust-lang/crates.io-index)" = "4227269cec09f5f83ff160be12a1e9b0262dd1aa305302d5ba296c2ebd291055"
-"checksum clap 2.28.0 (registry+https://github.com/rust-lang/crates.io-index)" = "dc34bf7d5d66268b466b9852bca925ec1d2650654dab4da081e63fd230145c2e"
+"checksum clap 2.32.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b957d88f4b6a63b9d70d5f454ac8011819c6efa7727858f458ab71c756ce2d3e"
 "checksum clipboard 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)" = "25a904646c0340239dcf7c51677b33928bf24fdf424b79a57909c0109075b2e7"
 "checksum clipboard-win 2.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "14cc3e6c075926b96490d5f90d4a5af7be8012a4d8a8698e619655085a7641a3"
 "checksum cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "ddfc5b9aa5d4507acaf872de71051dfd0e309860e88966e1051e462a077aac4f"
@@ -5344,15 +5446,18 @@ dependencies = [
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 "checksum derive_more 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3f57d78cf3bd45270dad4e70c21ec77a960b36c7a841ff9db76aaa775a8fb871"
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+"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>"
@@ -5450,6 +5555,8 @@ dependencies = [
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@@ -5594,15 +5701,16 @@ dependencies = [
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 "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"
+"checksum textwrap 0.10.0 (registry+https://github.com/rust-lang/crates.io-index)" = "307686869c93e71f94da64286f9a9524c0f308a9e1c87a583de8e9c9039ad3f6"
 "checksum thin-slice 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "8eaa81235c7058867fa8c0e7314f33dcce9c215f535d1913822a2b3f5e289f3c"
 "checksum thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c6b53e329000edc2b34dbe8545fd20e55a333362d0a321909685a19bd28c3f1b"
 "checksum thread_profiler 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "5920e77802b177479ab5795767fa48e68f61b2f516c2ac0041e2978dd8efe483"
@@ -5657,6 +5765,7 @@ 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/dom_struct/lib.rs

@@ -19,6 +19,7 @@ pub fn dom_struct(args: TokenStream, input: TokenStream) -> TokenStream {
         #[derive(DenyPublicFields, DomObject, JSTraceable, MallocSizeOf)]
         #[must_root]
         #[repr(C)]
+        #[webidl]
     };
 
     // Work around https://github.com/rust-lang/rust/issues/46489

components/script/Cargo.toml

@@ -17,7 +17,8 @@ debugmozjs = ['js/debugmozjs']
 profilemozjs = ['js/profilemozjs']
 unstable = []
 unrooted_must_root_lint = ["script_plugins/unrooted_must_root_lint"]
-default = ["unrooted_must_root_lint"]
+webidl_lint = ["script_plugins/webidl_lint"]
+default = ["unrooted_must_root_lint", "webidl_lint"]
 webgl_backtrace = ["backtrace", "canvas_traits/webgl_backtrace"]
 js_backtrace = ["backtrace"]
 

components/script/dom/testbindingproxy.rs

@@ -5,13 +5,13 @@
 // check-tidy: no specs after this line
 
 use crate::dom::bindings::codegen::Bindings::TestBindingProxyBinding::TestBindingProxyMethods;
-use crate::dom::bindings::reflector::Reflector;
 use crate::dom::bindings::str::DOMString;
+use crate::dom::testbinding::TestBinding;
 use dom_struct::dom_struct;
 
 #[dom_struct]
 pub struct TestBindingProxy {
-    reflector_: Reflector,
+    testbinding_: TestBinding,
 }
 
 impl TestBindingProxyMethods for TestBindingProxy {

components/script/dom/webidls/Window.webidl

@@ -72,9 +72,6 @@
 Window implements GlobalEventHandlers;
 Window implements WindowEventHandlers;
 
-[NoInterfaceObject]
-interface WindowProxy {};
-
 // https://html.spec.whatwg.org/multipage/#Window-partial
 partial interface Window {
   void captureEvents();

components/script/dom/webidls/WindowProxy.webidl

@@ -0,0 +1,7 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+// https://html.spec.whatwg.org/multipage/#the-windowproxy-exotic-object
+[NoInterfaceObject]
+interface WindowProxy {};

components/script_plugins/Cargo.toml

@@ -11,3 +11,7 @@ plugin = true
 
 [features]
 unrooted_must_root_lint = []
+webidl_lint = []
+
+[dependencies]
+webidl = "0.8"

components/script_plugins/lib.rs

@@ -25,12 +25,17 @@ extern crate rustc;
 extern crate rustc_plugin;
 extern crate syntax;
 
+extern crate webidl;
+
 use rustc_plugin::Registry;
 use syntax::feature_gate::AttributeType::Whitelisted;
 
 #[cfg(feature = "unrooted_must_root_lint")]
 mod unrooted_must_root;
 
+#[cfg(feature = "webidl_lint")]
+mod webidl_must_inherit;
+
 /// Utilities for writing plugins
 #[cfg(feature = "unrooted_must_root_lint")]
 mod utils;
@@ -40,7 +45,11 @@ pub fn plugin_registrar(reg: &mut Registry) {
     #[cfg(feature = "unrooted_must_root_lint")]
     reg.register_late_lint_pass(Box::new(unrooted_must_root::UnrootedPass::new()));
 
+    #[cfg(feature = "webidl_lint")]
+    reg.register_late_lint_pass(Box::new(webidl_must_inherit::WebIdlPass::new()));
+
     reg.register_attribute("allow_unrooted_interior".to_string(), Whitelisted);
     reg.register_attribute("allow_unrooted_in_rc".to_string(), Whitelisted);
     reg.register_attribute("must_root".to_string(), Whitelisted);
+    reg.register_attribute("webidl".to_string(), Whitelisted);
 }

components/script_plugins/webidl_must_inherit.rs

@@ -0,0 +1,222 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+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,
+    "Warn and report usage of incorrect webidl inheritance"
+);
+
+pub struct WebIdlPass;
+
+#[derive(Clone, Debug)]
+pub struct ParentMismatchError {
+    name: String,
+    rust_parent: String,
+    webidl_parent: String,
+}
+
+impl fmt::Display for ParentMismatchError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "webidl-rust inheritance mismatch, rust: {:?}, rust parent: {:?}, webidl parent: {:?}",
+            self.name, self.rust_parent, self.webidl_parent
+        )
+    }
+}
+
+impl Error for ParentMismatchError {
+    fn description(&self) -> &str {
+        "ParentMismatchError"
+    }
+
+    fn cause(&self) -> Option<&Error> {
+        None
+    }
+}
+
+impl WebIdlPass {
+    pub fn new() -> WebIdlPass {
+        WebIdlPass
+    }
+}
+
+fn get_ty_name(ty: &str) -> &str {
+    if let Some(i) = ty.rfind(':') {
+        &ty[i + 1..]
+    } else {
+        ty
+    }
+}
+
+fn get_webidl_path(struct_name: &str) -> io::Result<path::PathBuf> {
+    let mut dir = env::current_dir()?;
+    dir.push("components/script/dom/webidls/");
+    dir.push(format!("{}.webidl", struct_name));
+
+    Ok(dir)
+}
+
+fn is_webidl_ty(cx: &LateContext, ty: &ty::TyS) -> bool {
+    let mut ret = false;
+    ty.maybe_walk(|t| {
+        match t.sty {
+            ty::Adt(did, _substs) => {
+                if cx.tcx.has_attr(did.did, "webidl") {
+                    ret = true;
+                }
+                false
+            },
+            ty::Ref(..) => false,    // don't recurse down &ptrs
+            ty::RawPtr(..) => false, // don't recurse down *ptrs
+            ty::FnDef(..) | ty::FnPtr(_) => false,
+            _ => true,
+        }
+    });
+    ret
+}
+
+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();
+
+    if inherits == parent_name {
+        return Ok(());
+    }
+
+    // If there is no parent, first field must be of type Reflector.
+    if inherits == "" && parent_name == "Reflector" {
+        return Ok(());
+    }
+
+    if inherits == "" &&
+        name == "PaintRenderingContext2D" &&
+        parent_name == "CanvasRenderingContext2D"
+    {
+        // PaintRenderingContext2D embeds a CanvasRenderingContext2D
+        // instead of a Reflector as an optimization,
+        // but this is fine since CanvasRenderingContext2D
+        // also has a reflector
+        return Ok(());
+    }
+
+    Err(boxed::Box::from(ParentMismatchError {
+        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)?;
+    if let Some(parent) = parent_name {
+        let code = fs::read_to_string(path)?;
+        return check_inherits(&code, name, &parent);
+    }
+
+    Ok(())
+}
+
+impl LintPass for WebIdlPass {
+    fn name(&self) -> &'static str {
+        "ServoWebIDLPass"
+    }
+
+    fn get_lints(&self) -> LintArray {
+        lint_array!(WEBIDL_INHERIT_CORRECT)
+    }
+}
+
+impl<'a, 'tcx> LateLintPass<'a, 'tcx> for WebIdlPass {
+    fn check_struct_def(
+        &mut self,
+        cx: &LateContext<'a, 'tcx>,
+        def: &'tcx hir::VariantData,
+        n: ast::Name,
+        _gen: &'tcx hir::Generics,
+        id: HirId,
+    ) {
+        let def_id = cx.tcx.hir().local_def_id_from_hir_id(id);
+        if !is_webidl_ty(cx, cx.tcx.type_of(def_id)) {
+            return;
+        }
+
+        let item = match cx.tcx.hir().get_by_hir_id(id) {
+            hir::Node::Item(item) => item,
+            _ => cx
+                .tcx
+                .hir()
+                .expect_item_by_hir_id(cx.tcx.hir().get_parent_item(id)),
+        };
+
+        let parent_name = def.fields().iter().next().map(|field| {
+            let def_id = cx.tcx.hir().local_def_id_from_hir_id(field.hir_id);
+            let ty = cx.tcx.type_of(def_id).to_string();
+            get_ty_name(&ty).to_string()
+        });
+
+        let struct_name = n.to_string();
+        match check_webidl(&struct_name, &parent_name) {
+            Ok(()) => {},
+            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()
+            }
+        }
+    }
+}