Auto merge of #13700 - Manishearth:bindgen-testing, r=emilio

Run bindings tests with whole crate

We currently run bindgen's autogenerated `#[test]` blocks directly on the structs files.

That is, after generating them, we run `rustc --test` on them. This works fine for now, but
if you want to refer to types defined outside of these files (e.g. in https://bugzilla.mozilla.org/show_bug.cgi?id=1309165),
the tests are broken.

This puts a `cargo test -p style` in `./mach test-stylo`. I disabled doctests because they were failing (unable to find the `ns!()` and `atom!()` macros), and I couldn't figure out why -- will investigate in a later bug.

r? @emilio

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/servo/13700)
<!-- Reviewable:end -->

components/style/binding_tools/regen.py

@@ -11,7 +11,6 @@ import argparse
 import platform
 import copy
 import subprocess
-import tempfile
 
 import regen_atoms
 
@@ -42,7 +41,6 @@ COMPILATION_TARGETS = {
     # Generation of style structs.
     "structs": {
         "target_dir": "../gecko_bindings",
-        "test": True,
         "flags": [
             "--ignore-functions",
             "--ignore-methods",
@@ -540,49 +538,11 @@ Option<&'a {0}>;".format(ty))
         return 1
 
     print("OK")
+    print("(please test with ./mach test-stylo)")
 
     if verbose:
         print(output)
 
-    if current_target.get("test", False) and not skip_test:
-        print("[RUSTC]... ", end='')
-        sys.stdout.flush()
-
-        with tempfile.NamedTemporaryFile(delete=False) as f:
-            test_file = f.name
-        output = None
-        try:
-            rustc_command = ["rustc", output_filename, "--test", "-o", test_file]
-            output = subprocess.check_output(rustc_command, stderr=subprocess.STDOUT)
-            output = output.decode('utf8')
-        except subprocess.CalledProcessError as e:
-            print("FAIL\n", e.output.decode('utf8'))
-            return 1
-
-        print("OK")
-
-        if verbose:
-            print(output)
-
-        print("[RUSTC_TEST]... ", end='')
-        sys.stdout.flush()
-
-        try:
-            output = subprocess.check_output([test_file], stderr=subprocess.STDOUT)
-            output = output.decode('utf8')
-        except subprocess.CalledProcessError as e:
-            print("tests failed: ", e.output.decode('utf8'))
-            return 1
-
-        os.remove(test_file)
-        print("OK")
-
-        # TODO: this -3 is hacky as heck
-        print(output.split('\n')[-3])
-
-        if verbose:
-            print(output)
-
     return 0