Auto merge of #8996 - nox:rm-empty-modules, r=frewsxcv

Do not create modules from files with nothing to codegen (fixes #8711)

Fixes #8711.

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2 files changed, 16 insertions, 10 deletions

diff --git a/components/script/dom/bindings/codegen/BindingGen.py b/components/script/dom/bindings/codegen/BindingGen.py
index 5debf3e1f0f..6b1f10c44e2 100644
--- a/components/script/dom/bindings/codegen/BindingGen.py
+++ b/components/script/dom/bindings/codegen/BindingGen.py
@@ -18,8 +18,10 @@ def generate_binding_rs(config, outputprefix, webidlfile):
     """
 
     filename = outputprefix + ".rs"
-    root = CGBindingRoot(config, outputprefix, webidlfile)
-    if replaceFileIfChanged(filename, root.define()):
+    module = CGBindingRoot(config, outputprefix, webidlfile).define()
+    if not module:
+        print "Skipping empty module: %s" % (filename)
+    elif replaceFileIfChanged(filename, module):
         print "Generating binding implementation: %s" % (filename)
 
 
diff --git a/components/script/dom/bindings/codegen/CodegenRust.py b/components/script/dom/bindings/codegen/CodegenRust.py
index c84be59ad7c..c4bd53c42c1 100644
--- a/components/script/dom/bindings/codegen/CodegenRust.py
+++ b/components/script/dom/bindings/codegen/CodegenRust.py
@@ -5258,17 +5258,23 @@ class CGBindingRoot(CGThing):
         descriptors.extend(config.getDescriptors(webIDLFile=webIDLFile,
                                                  hasInterfaceObject=False,
                                                  isCallback=False))
-        dictionaries = config.getDictionaries(webIDLFile=webIDLFile)
 
-        cgthings = []
+        dictionaries = config.getDictionaries(webIDLFile=webIDLFile)
 
         mainCallbacks = config.getCallbacks(webIDLFile=webIDLFile)
         callbackDescriptors = config.getDescriptors(webIDLFile=webIDLFile,
                                                     isCallback=True)
 
-        # Do codegen for all the enums
-        cgthings = [CGEnum(e) for e in config.getEnums(webIDLFile)]
+        enums = config.getEnums(webIDLFile)
+
+        if not (descriptors or dictionaries or mainCallbacks or callbackDescriptors or enums):
+            self.root = None
+            return
 
+        # Do codegen for all the enums.
+        cgthings = [CGEnum(e) for e in enums]
+
+        # Do codegen for all the dictionaries.
         cgthings.extend([CGDictionary(d, config.getDescriptorProvider())
                          for d in dictionaries])
 
@@ -5288,10 +5294,6 @@ class CGBindingRoot(CGThing):
         # And make sure we have the right number of newlines at the end
         curr = CGWrapper(CGList(cgthings, "\n\n"), post="\n\n")
 
-        # Wrap all of that in our namespaces.
-        # curr = CGNamespace.build(['dom'],
-        #                          CGWrapper(curr, pre="\n"))
-
         # Add imports
         curr = CGImports(curr, descriptors + callbackDescriptors, mainCallbacks, [
             'js',
@@ -5390,6 +5392,8 @@ class CGBindingRoot(CGThing):
         self.root = curr
 
     def define(self):
+        if not self.root:
+            return None
         return stripTrailingWhitespace(self.root.define())