Auto merge of #14602 - upsuper:auto-copy-bindgen, r=Wafflespeanut

Auto-update in-tree bindings

Automatically update the in-tree bindings after a successful geckolib build with gecko dist specified.

cc @heycam @emilio

This is very similiar to the patch that @emilio provided yesterday, so I'd ask someone else to review.

r? @bholley

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python/servo/build_commands.py

@@ -24,7 +24,7 @@
     Command,
 )
 
-from servo.command_base import CommandBase, cd, call, BIN_SUFFIX, host_triple
+from servo.command_base import CommandBase, cd, call, BIN_SUFFIX, host_triple, find_dep_path_newest
 
 
 def format_duration(seconds):
@@ -401,7 +401,8 @@ def build_geckolib(self, with_gecko=None, jobs=None, verbose=False, release=Fals
         self.ensure_bootstrapped()
 
         env = self.build_env(is_build=True)
-        env["CARGO_TARGET_DIR"] = path.join(self.context.topdir, "target", "geckolib").encode("UTF-8")
+        geckolib_build_path = path.join(self.context.topdir, "target", "geckolib").encode("UTF-8")
+        env["CARGO_TARGET_DIR"] = geckolib_build_path
 
         ret = None
         opts = []
@@ -425,6 +426,15 @@ def build_geckolib(self, with_gecko=None, jobs=None, verbose=False, release=Fals
 
         print("GeckoLib build completed in %s" % format_duration(elapsed))
 
+        if with_gecko is not None and ret == 0:
+            print("Copying binding files to style/gecko_bindings...")
+            build_path = path.join(geckolib_build_path, "release" if release else "debug", "")
+            target_style_path = find_dep_path_newest("style", build_path)
+            out_gecko_path = path.join(target_style_path, "out", "gecko")
+            bindings_path = path.join(self.context.topdir, "components", "style", "gecko_bindings")
+            for f in ["bindings.rs", "structs_debug.rs", "structs_release.rs"]:
+                shutil.copy(path.join(out_gecko_path, f), bindings_path)
+
         return ret
 
     @Command('clean',

python/servo/command_base.py

@@ -50,12 +50,17 @@ def setlocale(name):
 
 def find_dep_path_newest(package, bin_path):
     deps_path = path.join(path.split(bin_path)[0], "build")
+    candidates = []
     with cd(deps_path):
-        candidates = glob(package + '-*')
-    candidates = (path.join(deps_path, c) for c in candidates)
-    candidate_times = sorted(((path.getmtime(c), c) for c in candidates), reverse=True)
-    if len(candidate_times) > 0:
-        return candidate_times[0][1]
+        for c in glob(package + '-*'):
+            candidate_path = path.join(deps_path, c)
+            candidate_output = path.join(candidate_path, "output")
+            if path.exists(candidate_output):
+                candidates.append((path.getmtime(candidate_output), candidate_path))
+    candidates.sort(reverse=True)
+    if candidates:
+        _, candidate_path = candidates[0]
+        return candidate_path
     return None