vs: support Generator outputs as CustomTarget inputs

This changes how generated files are added to the VS project.
Previously, they were all added as a single CustomBuildStep with all
generator commands, inputs and outputs merged together.
Now, each input file is added separately to the project and is given a
CustomBuild command. This adds all generator input files to the files list
in the VS gui and allows to run only some of the generator commands if
only some of the input files have changed.

mesonbuild/backend/vs2010backend.py

@@ -93,9 +93,6 @@ class Vs2010Backend(backends.Backend):
 
     def generate_custom_generator_commands(self, target, parent_node):
         generator_output_files = []
-        commands = []
-        inputs = []
-        outputs = []
         custom_target_include_dirs = []
         custom_target_output_files = []
         target_private_dir = self.relpath(self.get_target_private_dir(target), self.get_target_dir(target))
@@ -116,6 +113,7 @@ class Vs2010Backend(backends.Backend):
                 outfilelist = genlist.get_outputs()
                 exe_arr = self.exe_object_to_cmd_array(exe)
                 base_args = generator.get_arglist()
+                idgroup = ET.SubElement(parent_node, 'ItemGroup')
                 for i in range(len(infilelist)):
                     if len(infilelist) == len(outfilelist):
                         sole_output = os.path.join(target_private_dir, outfilelist[i])
@@ -132,18 +130,10 @@ class Vs2010Backend(backends.Backend):
                     args = [x.replace("@SOURCE_DIR@", self.environment.get_source_dir()).replace("@BUILD_DIR@", target_private_dir)
                             for x in args]
                     fullcmd = exe_arr + self.replace_extra_args(args, genlist)
-                    commands.append(' '.join(self.special_quote(fullcmd)))
-                    inputs.append(infilename)
-                    outputs.extend(outfiles)
-        if len(commands) > 0:
-            idgroup = ET.SubElement(parent_node, 'ItemDefinitionGroup')
-            cbs = ET.SubElement(idgroup, 'CustomBuildStep')
-            ET.SubElement(cbs, 'Command').text = '\r\n'.join(commands)
-            ET.SubElement(cbs, 'Inputs').text = ";".join(inputs)
-            ET.SubElement(cbs, 'Outputs').text = ';'.join(outputs)
-            ET.SubElement(cbs, 'Message').text = 'Generating custom sources.'
-            pg = ET.SubElement(parent_node, 'PropertyGroup')
-            ET.SubElement(pg, 'CustomBuildBeforeTargets').text = 'ClCompile'
+                    command = ' '.join(self.special_quote(fullcmd))
+                    cbs = ET.SubElement(idgroup, 'CustomBuild', Include=infilename)
+                    ET.SubElement(cbs, 'Command').text = command
+                    ET.SubElement(cbs, 'Outputs').text = ';'.join(outfiles)
         return generator_output_files, custom_target_output_files, custom_target_include_dirs
 
     def generate(self, interp):
@@ -205,8 +195,7 @@ class Vs2010Backend(backends.Backend):
                 for d in [target.command] + target.args:
                     if isinstance(d, (build.BuildTarget, build.CustomTarget)):
                         all_deps[d.get_id()] = d
-            # BuildTarget
-            else:
+            elif isinstance(target, build.BuildTarget):
                 for ldep in target.link_targets:
                     all_deps[ldep.get_id()] = ldep
                 for obj_id, objdep in self.get_obj_target_deps(target.objects):
@@ -218,6 +207,8 @@ class Vs2010Backend(backends.Backend):
                         gen_exe = gendep.generator.get_exe()
                         if isinstance(gen_exe, build.Executable):
                             all_deps[gen_exe.get_id()] = gen_exe
+            else:
+                raise MesonException('Unknown target type for target %s' % target)
         if not t or not recursive:
             return all_deps
         ret = self.get_target_deps(all_deps, recursive)
@@ -418,6 +409,7 @@ class Vs2010Backend(backends.Backend):
         ET.SubElement(customstep, 'Outputs').text = ';'.join(ofilenames)
         ET.SubElement(customstep, 'Inputs').text = ';'.join(srcs)
         ET.SubElement(root, 'Import', Project='$(VCTargetsPath)\Microsoft.Cpp.targets')
+        self.generate_custom_generator_commands(target, root)
         tree = ET.ElementTree(root)
         tree.write(ofname, encoding='utf-8', xml_declaration=True)
 

mesonbuild/build.py

@@ -1277,7 +1277,7 @@ class CustomTarget(Target):
         for c in self.sources:
             if hasattr(c, 'held_object'):
                 c = c.held_object
-            if isinstance(c, (BuildTarget, CustomTarget, GeneratedList)):
+            if isinstance(c, (BuildTarget, CustomTarget)):
                 deps.append(c)
         return deps
 
@@ -1402,8 +1402,17 @@ class CustomTarget(Target):
     def get_sources(self):
         return self.sources
 
+    def get_generated_lists(self):
+        genlists = []
+        for c in self.sources:
+            if hasattr(c, 'held_object'):
+                c = c.held_object
+            if isinstance(c, GeneratedList):
+                genlists.append(c)
+        return genlists
+
     def get_generated_sources(self):
-        return []
+        return self.get_generated_lists()
 
     def type_suffix(self):
         return "@cus"